Green Street Parking Garage East and West End Study City of Ithaca, New York

Transcription

1 Green Street Parking Garage East and West End Study City of Ithaca, New York FINAL Report Stantec PN: Prepared for: City of Ithaca 108 E. Green Street Ithaca, New York Prepared by: Stantec 61 Commercial Street Rochester, New York December 7, 2016

2 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Table of Contents EXECUTIVE SUMMARY... I COST PER PARKING SPACE FOR OPTION 4 BASED ON 30-YEAR LIFE... III 1.0 PURPOSE PROJECT LOCATION ORIGINAL GARAGE DESCRIPTION REFERENCES RECORD REVIEW REPAIRS REPAIRS REPAIRS REPAIRS RENOVATION AND ALTERNATIONS TO THE CENTER THIRD BARRIER REPAIRS STRUCTURAL AND WATERPROOFING REPAIRS EAST END AND WEST END EVALUATION FIELD SURVEYS VISUAL SURVEYS EAST AND WEST ENDS CONDITION SURVEY VISUAL CONDITION SURVEY STRUCTURAL Structural Design Criteria & Notes for Original Garage Constructed Slabs-on-grade: Elevated Slabs: Beams Columns Barrier Strands PRECAST CONCRETE PARAPET WALL PANELS WATERPROOFING SYSTEMS Deck Coatings Expansion Joints POST TENSION SYSTEM EVALUATION OVERVIEW AND PURPOSE FINDINGS Slabs Beams Summary Bulk Water and Evidence of Moisture Within the Cable Sheathing All Protective Grease Is Substandard

3 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK 4.3 CONCLUSION CONTINUED GARAGE OCCUPANCY TEMPORARY SHORING AT W7 EXPANSION JOINT REPAIR OPTIONS DESCRIPTION REPAIR OPTION 1 REPAIR OF BROKEN P/T; ADD EXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS FOR CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) REPAIR OPTION 2 COMPREHENSIVE P/T RESTORATION; ADD EXTERNAL BEAM P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) REPAIR OPTION 3 NEW P/T MINI-BEAMS; ADD EXTERNAL BEAM P/T SYSTEM AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) COMBINED REPAIR OPTIONS OPINION OF CONSTRUCTION COST INTRODUCTION REPAIR OPTION 1 REPAIR OF BROKEN P/T; ADD EXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS FOR CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) REPAIR OPTION 2 COMPREHENSIVE P/T RESTORATION; ADD EXTERNAL P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) REPAIR OPTION 3 NEW P/T MINI-BEAMS; ADD EXTERNAL P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) REPAIR OPTION 4A DECOMISSION EAST END; REPAIR WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR WEST END AND 50+- YEAR LIFE) REPAIR OPTION 4B DECOMISSION WEST END; REPAIR EAST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+- YEAR LIFE) REPAIR OPTION 4C REPAIRS TO EAST END AND WEST END; WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+- YEAR LIFE) COST PER PARKING SPACE FOR OPTION 4 BASED ON 30-YEAR LIFE LIST OF APPENDICES

4 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK APPENDIX A FIGURES... A.1 FIG 1 GROUND, SCOND & THIRD FLOOR... A.1 FIG 2 SECOND FLOOR PALN WEST - SURVEYSA.1 FIG 3 SECOND FLOOR PLAN EAST - SURVEYS... A.1 FIG 4 THIRD FLOOR PLAN WEST - SURVEYS... A.1 FIG 5 THIRD FLOOR PLAN EAST - SURVEYS... A.1 FIG 6 SOUTH ELEVATION WEST SECTION... A.1 FIG 7 SOUTH ELEVATION MIDDLE SECTION... A.1 FIG 8 WALL SECTION... A.1 FIG 9 SECOND FLOOR PLAN WEST OPTION 1... A.1 FIG 10 REPAIR OPTION 1 SECOND FLOOR PLAN EAST OPTION 1... A.1 FIG 11 REPAIR OPTION 1 THIRD FLOOR PLAN WEST OPTION 1... A.1 FIG 12 THIRD FLOOR PLAN EAST OPTION 1... A.1 FIG 13 SECOND FLOOR PLAN WEST OPTION 2... A.1 FIG 14 SECOND FLOOR PLAN EAST OPTION 2... A.1 FIG 15 SECOND FLOOR PLAN WEST OPTION 3... A.1 FIG 16 SECOND FLOOR PLAN EAST OPTION 3... A.1 FIG 17 SECOND FLOOR PLAN WEST OPTION 4... A.1 FIG 18 SECOND FLOOR PLAN EAST OPTION 4... A.1 FIG 19 ISOMETRIC OPTION 4 DEMILISH ENDS WITH EXPANSION FO CENTER SECTION... A.1 APPENDIX B OPINION OF PROBABLE CONSTRUCTION COST... B.3 APPENDIX C VECTOR REPORT... CB.3

5 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Executive Summary The purpose of this study is to provide sufficient information to City staff and elected officials on the condition of the East End and West End of the Green Street Parking Garage with specific focus on the concealed post-tension systems. The project started with an evaluation of the East End structure but field results from the East End evaluation lead to expanding the study to include an evaluation of the West End. The East and West ends of the current garage represent the original construction from 1974, whereas the center third is from a reconstruction project in This report will allow options to be compared and evaluated on the basis of sound technical and economic analyses. The projected costs are an extrapolation of the data developed on the structure in November and December 2015 surveys, previous studies and various follow-up visits. Studies included nondestructive testing, limited destructive sampling/testing and intrusive surveys. This study includes preliminary cost estimates for the options listed, including repair of East and/or West ends, demolition and replacement of East or West ends, and expansion of the center third. The investigation found that the garage has a large percentage of broken tendons throughout at both slabs and beams. The breakages tend to be significantly elevated at the Roof Level of the East Garage and Level 2 of the West Garage. The large number of broken or tension deficient cables are likely due to the ingress of water into the cable sheaths and from the anchor locations causing tendons to corrode. Each repair option addressed the widespread structural deficiencies to maintain service. For the purpose of this study, the options considered are as follows: REPAIR OPTION 1 - REPAIR OF BROKEN P/T AND EXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS FOR CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) Repair Option 1 addresses the current deficiencies in the structural capacity of slabs and beams but does not go forward with work to rejuvenate the remaining post tensioning system tendons to extend service. Under this Option, tendons will continue to fail and periodic repairs will be needed to repair additional tendons that fail over time. This option is basically a bandage to keep the garage open until demolition and rebuild or demolition to allow for other development. i

6 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK REPAIR OPTION 2 - COMPREHENSIVE P/T RESTORATION AND EXTERNAL BEAM P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING for CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) Repair Option 2 addresses the current deficiencies in the structural capacity of slabs and beams and using techniques to rejuvenate the remaining post tensioning system tendons. Under this Option, there is less probability that tendons will continue to fail. Periodic repairs should be planned over time but will be less frequent. The option also performs comprehensive repairs to structural slabs and replaces the waterproofing system. This option continues to rely on the existing post-tensioning system for continued service. REPAIR OPTION 3 - NEW P/T MINI-BEAMS AND EXTERNAL BEAM P/T SYSTEM AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) Repair Option 3 addresses the current deficiencies in the structural capacity of slabs and beams by adding new post tension to slabs by cutting in and casting posttensioned mini-beams and providing external post-tension system to the mini-beams. The option includes comprehensive repairs to structural slabs and replaces the waterproofing system. This option would not rely on the current P/T system for slabs and beams and the new systems would allow additional slab and beam tendons to fail without the need for action. REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) This option would perform limited structural repairs to allow for the existing east and west ends of the garage to remain open for a period of 2-3 years and provide for the construction of an additional four (4) levels. REPAIR OPTION 4A DECOMISSION EAST END; REPAIR WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR WEST END AND 50+YEARS AT CENTER PORTION) Option 4A is a combination of Repair Option 3 Repair West end and Option 4. This option would perform limited structural repairs to allow for the existing east end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the West end and construction of an additional four (4) levels to the center portion. REPAIR OPTION 4B DECOMISSION WEST END; REPAIR EAST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+YEARS AT CENTER PORTION) Option 4B is a combination of Repair Option 3 Repair East end and Option 4. This option would perform limited structural repairs to allow for the existing west end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the East end and construction of an additional four (4) levels to the center portion. ii

7 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK REPAIR OPTION 4C REPAIRS TO EAST END AND WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST AND WEST ENDS AND 50+YEARS AT CENTER PORTION) Option 4C would perform comprehensive Option 3 repairs to the East end and West Ends and construction of an additional four (4) levels to the center portion. This option would perform limited structural repairs to allow for the existing east end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the West end and construction of an additional four (4) levels to the center portion. COST PER PARKING SPACE FOR OPTION 4 BASED ON 30-YEAR LIFE The cost per space for the different Option 4 scenarios based on the number of parking spaces is as follows: Configuration Option 4 Decommission East and West Plus Center Expansion (4 levels) See Note 1 Option 4A Decommission East & Repair West Plus Center Expansion (4 levels) Option 4B Decommission West and Repair East Plus Center Expansion (4 levels) Option 4C Repair East and West Plus Center Expansion Number of Spaces (Includes Grade Level) Opinion of Cost Cost per Parking Space 236 $13,760,000 $58, $17,630,000 $34, $16,850,000 $32, $20,750,000 $30,100 Note 1 - The life expectancy of an expansion would be greater than 30 years but 30 years used in this evaluation. iii

8 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Purpose December 7, PURPOSE The purpose of this study is to provide sufficient information to City staff and elected officials on the condition of the East End and West End of the Green Street Parking Garage with specific focus on the concealed post-tension systems. The project started with an evaluation of the East End structure but field results from the East End evaluation lead to expanding the study to include an evaluation of the West End. The East and West ends of the current garage represent the original 1974 construction, whereas the center third is from a reconstruction project in This report will allow options to be compared and evaluated on the basis of sound technical and economic analyses. It should be understood that the Options evaluated do not represent all potential variations of renovation combinations, but cover a wide range of viable possibilities. The projected costs are an extrapolation of the data developed on the structure in November and December 2015 surveys, previous studies and various follow-up site visits thru November The status of the concealed posttension systems was evaluated by Vector Technologies Inc. (Vector) to provide information on the concealed beam and slab post tension system. Vector performed nondestructive testing, limited destructive sampling/testing and intrusive surveys. Predicting the scope and complexity of repair programs was based on current conditions and the repair history of the Green Street Parking Garage. This study includes preliminary costing for the options listed that includes repairs, demolition and replacement and expansion of the existing center section. 1.1 PROJECT LOCATION The Green Street Parking Garage is located in downtown Ithaca New York. The location of the building is depicted in Figure 1-1. gg u:\ \management\report\final\green street parking garage study_final draft.docx 1.1

9 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Purpose December 7, 2016 Figure 1-1 Project Location 1.2 ORIGINAL GARAGE DESCRIPTION The Green Street Parking Garage was constructed in by Sarkesian Brothers. The structural engineer was Severud Perrone Sturm Bandel of New York. The firm designed the helixes, stairs and other components. T.Y. Lin & Associates of San Francisco was the structural designer of the frame (columns, beams, slabs, bridges). The garage consists of two original flat elevated decks joined by an internal ramped slab. Access from grade is via an internal speed ramp. Refer to Figure 1-1. Expansion joints occur at column lines W7-1 and 11-E1 dividing the garage into three sections of approximately 180, 233, and 180 feet long. The garage construction is conventionally reinforced concrete foundations and columns. The concrete beams and one-way slabs are post-tensioned reinforced. The perimeter of the garage is bordered by precast concrete parapet wall panels, cast-inplace parapets and other barrier systems. gg u:\ \management\report\final\green street parking garage study_final draft.docx 1.2

10 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Purpose December 7, 2016 The garage, costing approximately $1,200,000 in 1974, was built and financed for the City of Ithaca by the New York State Urban Development Corporation (UDC), a governmental agency created by the State of New York. The entire responsibility for the project debt was assumed through the City of Ithaca General Fund. gg u:\ \management\report\final\green street parking garage study_final draft.docx 1.3

11 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK References December 7, REFERENCES 2.1 RECORD REVIEW Original design drawings were provided prior to the commencement of the study. The project documents were for the construction of the Rothchild s Department Storm and Parking Facility, Ithaca, New York. The drawings provided included the architectural and structural engineering disciplines dated June No specifications, post-tension drawings or shop drawings were provided. Renovation drawings were supplied for the Green Street Parking Garage Renovations and Alterations, City of Ithaca prepared by Carl Walker Parking, Shears Adkins, Hunt Engineers and Trowbridge and Wolf LLP dated April REPAIRS The 1978 repairs responded to a number of early age deficiencies occurring in slab and bridge surfaces. Portions of the deck slabs were coated with an elastomeric urethane membrane. The half-helix surface was likewise coated while the double helix remained uncoated REPAIRS By 1984, the double helix slabs had begun to deteriorate. Symptoms were radial and pattern cracking, vertical cracking in the exterior parapets and spalling of concrete decks and curbs. The helix slabs were found to be spalled and wheel abrasion had begun to wear depressions in the concrete along the routes of the wheel paths. Concrete and waterproofing repairs were performed to helix ramp slabs REPAIRS The double helix and half helix slabs were deteriorated with slab delaminations and cracking. The repair work continued until 1992 with a cost of over $1,100,000. gg u:\ \management\report\final\green street parking garage study_final draft.docx 2.1

12 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK References December 7, REPAIRS Concerns over the double helix slabs resulted in emergency repairs to the double helix, helix and bridge over East Green Street. Vertical shoring and knee brace elements were added to the helix slab to provide additional support. Repairs and expansion joint plates were added to the structures at the joint between the helix slabs and bridge slabs to address depressions. Seismic repairs were added to the bridge supports RENOVATION AND ALTERNATIONS TO THE CENTER THIRD A major reconstruction project was performed to the center third of the garage in 2006 thru The work included demolishing and reconstructing a ramped center third of the garage providing vehicle access between levels. The project also included demolition of the double helix, half helix and bridges between the helix and garage. The project included other access and functional upgrades. Structural repairs and application of deck coatings were applied to the east and west ends. The work included stair and elevator upgrades in the renovated space BARRIER REPAIRS The barrier strands along the south perimeter and the west end had pulled off the existing column attachment and failed. The west end was the result of vehicle impact while the south perimeter barrier is assumed to have failed by a vehicle inadvertently pulling cable strands. The impact damaged the existing column near the attachment. It was determined that the re-attachment of the barrier strand bracket to the column was not recommended due to the extent of repairs to the damaged column and high stresses produced by the barrier strand attachment. To re-establish the barrier at the west end, concrete posts were cast to the deck and standard guardrail attached to the new columns STRUCTURAL AND WATERPROOFING REPAIRS Structural repairs and waterproofing were performed at the Green Street Parking Garage as part of the Seneca Street Priority 4 project. The lower column supporting Level 2 at column Line B7 was repaired. Waterproofing repairs consisted of repairs at both Level 2 and Level 3 to address conditions contributing to leakage inside Thompkins Trust below the garage. The leakage was typically coming from deficient conditions around drains and thru-slab sleeves that were leaking. Tompkins Trust was not accessed as part of the repair process. gg u:\ \management\report\final\green street parking garage study_final draft.docx 2.2

13 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK References December 7, EAST END AND WEST END EVALUATION FIELD SURVEYS A majority of the field reconnaissance at the garage performed by Stantec and Vector was performed between November 9th and November 10th 2015 with a second field survey between December 20th and December 23rd Other Stantec site visits were also conducted at various times through November 2016 to review specific conditions. Photographs from the field survey are embedded in the narrative. The conditions and repair schemes are included in the Appendix A - FIGURES. The Vector report is included in Appendix C. gg u:\ \management\report\final\green street parking garage study_final draft.docx 2.3

14 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, VISUAL SURVEYS EAST AND WEST ENDS 3.1 CONDITION SURVEY The investigations included a condition survey generally in accordance with the American Concrete Institute ACI 201.1, Guide for Making a Condition Survey of Concrete in Service, and ACI Guide for Evaluation of Concrete Structures Prior to Rehabilitation. Pertinent items considered in this study included the following: Examination of original design drawings and the Green Street Parking Garage Renovations and Alterations Drawings; Evaluation of repair history; Surface condition of concrete; o Cracks: width, location, frequency, type o Scaling o Spalls o Corrosion o Efflorescence o Exposed and/or corroded steel reinforcement o Condition of prior repairs o Surface coatings o Abrasion Interior condition of concrete elements; o Cover over reinforcing steel o Delaminations Freeze-thaw distress; and General garage conditions o Drainage o Maintenance 3.2 VISUAL CONDITION SURVEY The following structural elements were examined: Post-tensioned concrete deck slabs and their precast concrete filigree panels below; Concrete deck coatings; Post-tensioned concrete beams; Reinforced concrete columns; and Precast concrete parapet walls and their welded anchors to concrete deck and columns gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.4

15 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, STRUCTURAL Structural Design Criteria & Notes for Original Garage Constructed 1974 Design Live Loads (T.Y. Lin &Associates Drawings) Second Floor Third Floor 50 pounds per square foot 65 pounds per square foot Structural Notes Concrete Compressive Strength: Reinforcement Prestress Stirrups All other Reinforcement 4,000 psi at 28-days 270 ksi strand fy = 40 ksi fy = 60 ksi Slabs-on-grade: Concrete slabs at the east end are covered by finishes as part of the Rothchild s Building. Concrete slabs at the east and west ends are original 5 thick slabs reinforced with welded wire. There was random cracking throughout the slab-on-grade area. There was cracking typical for slab-on-grade construction. The cracking was not considered serious unless cracks open up further or settlement becomes a problem. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.5

16 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 1 Concrete slab at trash contactor and storage areas as part of construction. Slabs in good condition. Photo 2 Concrete slab in walkway between Commons walkway and Seneca Street Sidewalk. Slabs in good condition and currently supporting foundation pads Elevated Slabs: Typical slabs are post-tensioned 7-1/2 thick slabs including a bottom 2-1/2 filigree slab. Slabs are reinforced by sheathed 270 ksi cables post tensioned to a specified force. The major defects include cracking, delaminations and minor spalls. The Level 3 deck contained more obvious spalls, potholes and failure of previous patches. The worst region of the Level 3 deck is the southern longitudinal section of the garage from the former half helix to the center third. Historically, increased traffic at this location of the garage lead to abrasion from wear along and tracking of de-icing salt which may have caused the increased slab deterioration. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.6

17 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 3 Level 3 West deck with delaminations, spalls and failed waterproofing Photo 4 Level 3 West deck with spall and failed waterproofing. Spall collects water and can enter tendon sheathing. Photo 5 Level 3 West deck with recent slab repair and waterproofing. Photo 6 Level 3 East deck in better condition. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.7

18 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 7 Level 2 East deck in better condition. Photo 8 Level 2 West deck in better condition but with scrapes and failed deck coating in locations Delamination Survey - East End Slabs Chain drag surveys were conducted to detect delaminations at three (3) total locations. The results are depicted in Table 3-1 Table 3-1 East End Delamination Survey Area Survey (SF) Delaminated Areas (SF) Percent Delaminated Level 2 1, % Level 3 2, % gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.8

19 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, Delamination Survey West End Slabs Chain drag surveys were conducted to detect delaminations at seven (7) total locations. The results are depicted in Table 3-2. Table 3-2 West End Delamination Survey Area Survey (SF) Delaminated Areas (SF) Percent Delaminated Level 2 4, % Level 3 3, % Beams The East End of the garage has eight (8) post tensioned beams while the west end has seven (7) post tensioned beams. There are no shop drawings so the precise number of tendons per beam is unknown. Based on beam design criteria shown on the original design drawings, we estimate the following tendon totals per beam. Level Column Lines Probable number of Tendons Level 2 W1, E8 14 Level 2 W2, W3, W4, W5, W6, E2, 21 E3, E4, E5, E6, E7 Level 2 W7, E1 11 Level 3 W1, E8 16 Level 3 W2, W3, W4, W5, W6, E2, 23 E3, E4, E5, E6, E7 Level 3 W7, E1 12 The beams in this structure were observed for cracks, delamination, excessive deflection and other visible defects East End Beams Only the Level 3 beams (roof level beams) could be surveyed due to the concealed finishes at Thompkins Trust. Level 3 beams were generally in good condition with some transverse cracking and evidence of slight sagging. The east end beam at the expansion joint exhibited more cracking and deterioration than beams away from the expansion joint. The sagging could be from long term creep. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.9

20 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 9 Level 3 East deck beam and column. Elements in good visual condition. P/T defects discussed later in report. Photo 10 Level 3 East deck beam and column. Elements in good visual condition. P/T defects discussed later in report. Photo 11 Level 3 East End beam at column E1. Beam is damaged by leaking joint. Repaired multiple times with latest in P/T defects discussed later in report. Photo 12 Level 3 East End beam at column lines 11 and E1. Beam is damaged by leaking joint. Repaired multiple times with latest in P/T defects discussed later in report. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.10

21 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, West End Beams Level 2 and Level 3 West end beams were surveyed. The beams were generally in good condition with some transverse cracking and slight sagging except for the beam at expansion joint at column line W7 which exhibited significant sagging and widespread cracking. The top-of-slab at the roof deck was similarly sagging with the largest sagging at midspan. The sagging could be from long term creep. The expansion joint beam had been repaired multiple times while in service with the most recent during the rehabilitation. See discussion later in report for additional findings. Spandrel beams (beams at west end bay) were in excellent condition. Photo 13 Level 3 West deck beam and column. Elements in good visual condition away from expansion joint. P/T defects discussed later in report. Photo 14 Level 3 West deck beam and columns at Column Line W7. Beam damaged by leaking expansion joint resulting in broken P/T tendons and sagging beam. P/T defects discussed later in report. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.11

22 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, Columns The columns are typically 18 x 24 except at expansion joints were columns were 15 x 18. Columns were generally in good condition except adjacent to expansion joints. These columns were deteriorated and were repaired as part of Seneca Street Priority 4 project in October Two (2) other columns were damaged by barrier strand release repaired in Photo 15 (2012 image) East end column Lines 11-E1 supporting Level 3. Column damaged by release of the barrier strand anchor bracket. Photo 16 (2015 image) East end column lines 12-E1 supporting Level 3. Damaged column following repair. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.12

23 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 17 (2013 image) West end column W1-B supporting Level 3. Column damaged by vehicle impact. Photo 18 (2015 image) West end column W1-B supporting Level 3. Restored column and replacement barrier restraint Barrier Strands Barrier cables provide restraint along all the perimeter elevations except at areas with a more robust panel restraint added with the construction. Cables are ½ diameter, hot dipped galvanized seven strand wire. Cables are secured to angles or bent plates secured to columns. The bent plates at Level 2 extended out from the column by a concrete block to provide the dimensional clearance away from the columns as needed for a straight cable run between attachments. Cables are supported intermittently by vertical guideposts. The barrier restraints were added to the East end and West end as part of the construction. The barrier restraint at the west elevation failed as the result of a vehicle impact. The angle anchors pulled out from the column face. The barrier restraint was replaced with a conventional highway style guardrail mounted to the new stub columns cast on the concrete deck in 2014 rather than re-attaching to the repaired column. A similar anchor failure occurred at column line E1 along the south elevation. The column was repaired in 2013 but the barrier restraint has not been installed. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.13

24 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 19 East End column E1 at Level 3 added as part of reconstruction project. Attachment extends off face of column resulting in inadequate anchoring in some cases. Level 2 barrier strands have failed. Photo 20 East End column E8 at Level 2 added as part of reconstruction project. Attachment of bent plates to column face performing as intended. 3.4 PRECAST CONCRETE PARAPET WALL PANELS The precast concrete wall panels provide an exterior façade treatment for the garage, protect persons from falling off the decks, and provide vehicle restraint. The panels appear to be cast from high-quality and durable concrete as there are very few material defects. They have not been exposed to severe chloride contamination, except those adjacent leaking joints above. The panels are attached to the concrete columns and decks with steel anchors. These anchors consist of steel plates embedded into both the panel and into the deck or column and field welded to make the attachment. Responding to concerns over panel attachments, barrier strands or guardrails have been added as part of the reconstruction. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.14

25 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 21 Typical Level 3 precast panel with added clip angle adjacent original anchor. Barrier strand was added as part of the construction. Photo 22 Typical Level 3 precast panel with added clip angle adjacent original anchor. Appears that welds have cracked at original anchor. 3.5 WATERPROOFING SYSTEMS Deck Coatings East End and West End: The current traffic bearing deck coating was replaced or topcoated in the renovation project. The installed topcoat is generally in fair to poor condition with failure at high wear locations typically at drive lanes and turn lanes. The worst conditions are at the west end roof level between the west end and expansion joint. The coating has failed at locations with severe delaminations or spalls. Based on the higher level of concrete deterioration, the underlying waterproofing component of the system is not performing as a barrier coating and may even be trapping water. The East End waterproofing is in much better condition likely due to lower usage and traffic patterns. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.15

26 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 Photo 23 Level 3 West End coating restored in with significant defects and patches where repairs performed. Photo 24 Level 2 West End coating restored in with loss of topcoat, defects and failure Expansion Joints Expansion joints occur at column lines W7 and 1 and column lines 11 and E1 dividing the garage into three sections 180, 233, and 180 feet long. These joints allow free thermal movement (expansion and contraction) in the structure. The current expansion joints are expansion joint gland anchored by elastomeric concrete nosing style joints. East End Expansion Joint (Column Lines 11 and E1) East end expansion joints appear to be performing as intended although there are some signs of leakage at the Level 3 joint. Failure of the expansion joint gland allows chloride contaminated water to saturate beam surfaces situated on either side of the joint. West End Expansion Joint (Column Lines W7 and 1) The Level 3 expansion joint has failed with significant vertical displacement between the west end and center section. The greatest sagging occurs at roughly midspan and gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.16

27 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Visual Surveys East and WEst Ends December 7, 2016 is lessens at the support. Approximate stringline measurements on the top of slab indicate a 1-1/2 deflection near midspan. Photo 25 Level 2 East deck expansion joint at column lines 11-E1. There Is minimal sagging and structural concerns are low. Photo 26 Level 3 East deck to building expansion joint at column line A. All joint glands will require periodic maintenance and replacement. Photo 27 Level 3 West deck expansion joint at column lines W7. There Is sagging up to 1-1/2 near midspan. Other exploration found a significant number of failed tendons. Photo 28 Level 3 West deck expansion joint at column lines W7-1. There Is sagging on west side of joint up to 1-1/2 near midspan. Other exploration found a significant number of failed tendons. Shoring was added for support. gg u:\ \management\report\final\green street parking garage study_final draft.docx 3.17

28 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, POST TENSION SYSTEM EVALUATION 4.1 OVERVIEW AND PURPOSE Stantec teamed with Vector Corrosion Technologies Ltd. (Vector) to perform an evaluation of the slab and beam post-tension system. The purpose of Vector s evaluation was to: Determine the extent of tension deficient tendons; Confirm the quality and quantity of the protective grease within the tendon sheath; Asses the moisture level in the tendon environment (air within tendon sheathing); and Determine the locations of any identified cable deficiencies (where possible). The evaluation was conducted in two (2) phases. Phase one (East End) was the originally contracted work and was conducted November 10 th and November 11 th Phase two (West End) was added to the scope and conducted December 21 st thru December 23 rd For Phase one, Vector was assisted by Crane-Hogan Structural Systems Inc. (Crane-Hogan). Crane Hogan provided access and executed patching of select holes at beams, driving surface holes and others not receiving the cover panel. Vector self-performed all work during Phase two including all access, patching and installation of cover panels. A scissor lift was used to collect the Level 2 soffit information Methodology Stantec and Vector collaborated to develop an appropriate scope of work based on a two (2) day field activity for the East End with an expanded three (3) day field activity for the West End. Specific Tests and significance of these tests performed include the following: Test #1 - Probes (Test wells) for Tendon evaluation Probes are performed to evaluate the conditions of the tendons including: Extent and severity of corrosion; Presence of any broken wires or broken tendons; Whether the strand is under-tensioned; Quantity and condition of the protective grease; and Extent of bulk water (if any) within the tendon sheath gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.18

29 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Probes were conducted at tendon low points to determine whether the tendons/wires were broken or not, and to determine the most appropriate effective repair solution. The probes were generally an 8 x 8 hole excavated approximately 2-3 deep to expose the strand, allow a visual inspection and further probe of individual wire strands with hand tools to identify the degree of tensioning. After the examination, the probe holes were filled with repair mortar or a cover panel attached to allow periodic observation in the future. Generally the cover panels were installed at locations not subject to traffic. Probe with cover plates can remain open to allow for future review. At holes with cover plates, the holes were filled with insulation and covered with a galvanized steel plate. Future inspection can be performed by removing the cover plate fasteners. Test #2 - Post-tensioned Tendon Corrosion Potential Evaluation (CPE) Corrosion Potential Evaluation (CPE) for selected tendons was performed to evaluate the moisture within the cable and future corrosion potential. Unbonded tendons include anchorage, strand, grease, plastic sheath housing around the strand and grease. Water and moisture can ingress into the sheath over the years from the anchor pockets or at damaged locations in the sheath. Once the water and moisture gets trapped in the sheath, there is no exit for the water or moisture to escape, creating a highly corrosive environment for the steel wire strands, eventually leading to strand breakage. The CPE Testing correlates moisture content to the potential for corrosion of the tendons using a proven identification system. If the cables are found to be wet, there are methods such as drying and re-greasing technologies that may be options. The results from this method will have great value in predicting the future concerns with the parking garage. The testing process is generally as follows: Drill small holes into the slab or beam concrete to access the tendon sheath near the end anchorages; Insert and secure air ports; Extract air samples by a pump. Measurements of the relative humidity and temperature of the air escaping from each of the out ports are obtained using a calibrated Relative Humidity & Temperature (RH & T) sensor. Establish the degree of wetness of each tendon by grading the moisture content of the escaping air and correlate the moisture content to the corrosion potential of the strands. Test #3 Cable Extraction Cable extraction consists of removing sections of cables from inspection openings to determine locations of cable deficiency and corrosion. This test will identify where gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.19

30 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 tendons are broke corresponding to a location most susceptible to breakage. This information will better define repair options. Tests Performed The evaluation included the following work: Reviewing existing structural drawings; Creating 68 inspection openings by removing concrete around the cable; Visually inspecting the cables and grease for signs of corrosion; Impact testing with hand tools each cable to determine the degree of tension within the cable; Corrosion Potential Evaluation by testing the moisture level of the air within the sheath; and Extracting broken sections of cables at 2 locations to determine the cause and location of breakage. Following the testing, the locations were patched or cover plates Installed to allow for periodic testing. 4.2 FINDINGS There Is a High Percentage of Tension Deficient Tendons Within the Test Sample Slabs The percentage of tension deficient cables within the test sample is moderate to high, which suggests the potential for widespread tendon tension issues. The overall percent of tension deficient tendons in the East and West garage sections was 15.4% (6 of 39 cables tested). The highest tension deficient percentages were concentrated to the Roof Level of the East Section and Level 2 of the West Section. The results of the East End Slab Cables are depicted in Table 4-1. Table 4-1 East End Slab Cables Level 2 Level 3 (Roof Level) No. Slab Openings 5 EA No. Slab Openings 17 EA Total # of Cables Tension 7 EA Total # of Cables Tension 32 EA Tested Tested Total # of Tension Deficient 0 EA Total # of Tension Deficient 6 EA Cables Cables % Tension Deficient Cables 0.0% % Tension Deficient Cables 18.8% Average Slab Cable Tension 15.4% Deficiency % (Level 2 and Level 3) gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.20

31 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Photo 29 Level 3 soffit - East deck. Chipping to open hole for tendon inspection and to check for stressing and presence of water in sheathing. Photo 30 Level 3 soffit - East deck. Chipping to partially open holes for tendon inspection to check for stressing and presence of water in sheathing. Photo 31 Level 3 soffit - East deck. Fully exposed paired tendons. Remove sheathing to allow for water detection and grease evaluation. Photo 32 Level 3 soffit - East deck. Fully exposed paired tendons with sheathing removed. Grease Is in poor condition with some moisture and signs of corrosion. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.21

32 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Photo 33 Level 3 soffit - East deck. Exposed paired tendons with sheathing removed. Corrosion protection evaluation (CPE) - Moisture testing is in progress. Photo 34 Level 3 - East end beam. Fully exposed three tendons with sheathing removed. Corroded conditions with hand probe indicating failed tendon. The results of the West End Slab Cables are depicted in Table 4-2 Table 4-2 West End Slab Cables Level 2 Level 3 (Roof Level) No. Slab Openings 15 EA No. Slab Openings 16 EA Total # of Cables Tension 17 EA Total # of Cables Tension 28 EA Tested Tested Total # of Tension Deficient 3 EA Total # of Tension Deficient 1 EA Cables Cables % Tension Deficient Cables 17.6% % Tension Deficient Cables 3.6% Average Slab Cable Tension 8.8% Deficiency %(Level 2 and Level 3) gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.22

33 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Photo 35 Level 3 soffit - West deck. Exposed paired tendons with sheathing removed. Grease Is in poor condition with water present. Photo 36 Level 3 - West end beam. Fully exposed tendons with sheathing removed. Corroded tendons with hand probe indicating failed tendon. Photo 37 Level 2 - West end beam. Tendons protected with specialty tape before installing cover panel. Photo 38 Level 3 - West end deck with series of openings with cover panel installed Beams The East and West ends of the garage representing the original construction exhibited a percentage of tension deficient cables within the test sample that is high, which suggests widespread tendon tension issues. The overall percent of tension deficient tendons in the East and West garage sections was 27.4% (25 of 91 cables tested) but less if column line W7 is not included in the data set 19%. The highest tension deficient percentages were concentrated to roof level at the East Section and Level 2 of the West Section. The results of the East End Slab Cables are depicted in Table 4-3 gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.23

34 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Table 4-3 East End Beam Cables Level 2 Level 3 (Roof Level) No. Beams Tested 1 EA No. Beams Tested 5 EA Total # of Cables Tension 1 EA Total # of Cables Tension 23 EA Tested Tested Total # of Tension Deficient 0 EA Total # of Tension Deficient 5 EA Cables Cables % Tension Deficient Cables 0.0% % Tension Deficient Cables 21.7% Average Beam Cable Tension 20.8% Deficiency % (Level 2 and Level 3) The results of the West End Beam Cables are depicted in Table 4-4 Table 4-4 West End Beam Cables Level 2 Level 3 (Roof Level) No. Beams Tested 4 EA No. Beams Tested 5 EA Total # of Cables Tension 33 EA Total # of Cables Tension 34 EA Tested Tested Total # of Tension Deficient 9 EA Total # of Tension Deficient 11 EA Cables Cables % Tension Deficient Cables 27.3% % Tension Deficient Cables 32.4% % Tension Deficient Cables Not including Beam at Column Line W7 8.0% Average Beam Cable Tension 19.0% Deficiency % (Level 2 and Level 3 - Not Including Beam W7) Summary The testing found a high percentage of tension deficient tendons within the test sample. This high percentage suggests widespread tendon tension issues. The overall percent of tension deficient tendons in the East and West garage sections was 16% (26 of 166 cables tested, not including the beam at gridline W7). The highest tension deficient percentages were concentrated to the Roof Level of the East Section and Level 2 of the West Section. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.24

35 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 The Summary totals for all post-tensioned slab and beams are depicted in Table 4-5 Table 4-5 All Slab and Beam Cables Overall Tension Deficiency % (All Levels in East and West Ends Not including Beam 7) 15.7% Bulk Water and Evidence of Moisture Within the Cable Sheathing. Bulk water or elevated moisture levels were detected in many tendons inspected. Any moisture within the sheath creates an environment for corrosion to occur. At many locations where bulk water was observed, cables also exhibited significant corrosion. For those tendons where bulk water was not evident the CPE was performed. CPE testing is not useful if there is already bulk water present. The moisture levels measured indicate that the cables fall within the Wet/Dry Zone on our corrosion classification system (see Appendix B of Vector Technologies Report). This indicates that corrosion may be occurring or that future corrosion is probable. The Summary totals for all post-tensioned slab and beams are depicted in Table 4-6 Table 4-6 CPE Testing for Slab and Beam Cables East Level 2 East Level 3 (Roof Level) No testing due to Thompkins No. Openings Tested 12 EA Trust space below Total # Cables in the Wet / 12 EA Dry Zone Total # Cables in the Wet 0 EA Zone West Level 2 West Level 3 (Roof Level) No. Openings Tested 4 EA No. Openings Tested 8 EA Total # Cables in the Wet / 3 EA Total # Cables in the Wet / 4 EA Dry Zone Dry Zone Total # Cables in the Wet Zone 1 EA Total # Cables in the Wet Zone 4 EA All Protective Grease Is Substandard Further contributing to the degradation of the cable systems was the absence of adequate protective cable grease on an overwhelming majority of the cables. All gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.25

36 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 cables contained a combination of emulsified, dehydrated or an inadequate volume of grease Cable Extraction The work at the West end included extracting cables at two locations to determine the cause and location of breakage. The extraction was performed by attaching hardware and chain to the broken tendon near midspan (low point) and pulling the chain with a motor vehicle. One roof level slab tendon was extracted at the West End located in the first bay in from the perimeter on the north side. One roof level beam tendon was extracted at the East end located in the north beam near the mid-beam span. West end extraction efforts also included attempt to remove a beam tendon and an additional slab tendon but this was not successful. It is concluded that the tendons are bound within the sheathing and could not be safely pulled with the equipment present. It also provides an opinion that the beam tendon cables would be very difficult to remove and replace in-place. Photo 39 Level 3 - West end deck Cable 2 removed at slab with broken tendon. Extraction found that tendon break occurred near anchor. Tendon contained limited grease and severe corrosion at anchor. Photo 40 Level 3 - East end beam Cable 6 removed at beam opening. Tendon break occurred near mid-span (low drape). Tendon with more grease but with corrosion at point of failure. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.26

37 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Once water is within the sheath, it tends to collect at the low drape points of the tendon, which along with anchor locations is also the most likely location for cable corrosion to occur. Cable 6 of beam opening *C as per DWG A / S1 (See appendix A of Vector Report) was extracted and found to be corroded and broken at the low drape of the North span. Cable 2 of Opening *C as per DWG B / S3 which was found broken and severely corroded at the North end anchor. It also confirms that the beam tendon cables would be very difficult to remove and replace cables in-place. 4.3 CONCLUSION The garage has a large percentage of broken cables at both slabs and beams. The breakages tend to be elevated on the Roof Level of the East end and Level 2 of the West end. The large number of broken or tension deficient cables are likely due to the ingress of water into the cable sheaths or from the anchor locations causing corrosion of the tendons. This corrosive activity has been compounded by the insufficient and dry grease. A repair strategy should include removing the existing moisture from the cables, encapsulating the cables with new grease and waterproofing the anchor ends to reduce the risk of water ingress or a repair to provide additional capacity. 4.4 CONTINUED GARAGE OCCUPANCY Due to the number of tension deficient tendons for slabs and beams, close and frequent review of garage components is warranted. Recommendations for continued use primarily relate to beams where capacity has been impacted. The beam locations with restrictions are as follows: East End Level 2 - Column Line W5 between Column lines B and C (South Part) There were five (5) broken beam tendons out of an estimated twenty-four (24) total tendons in the noted beam. It is possible there may be other tendons that are deficient but could not be identified by the testing activity. This beam is not exhibiting visual symptoms of distress or perceived deflection (sagging) similar to the beam observed at the expansion joint at W7. However, there is limited or no residual capacity in the beam beyond the current parking restrictions and service loads. Although the current status is of concern, it should be noted that these conditions are much less critical than the W7 beam discussed below where likely the majority of beam tendons were detensioned. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.27

38 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, 2016 Recommendation: Restrict all parking in the two bays adjacent the beam and closely monitored until comprehensive repairs are made. The beam should be visually inspected every two months for additional distress or signs of change. Top of slab elevations should be obtained to benchmark any existing deflection (sagging). If there are continued signs of distress or sagging, then the beam should be reinforced or shored to grade. Level 3 - Column Line W7 between Column lines A and C (entire width) The evaluation uncovered nine (9) broken beam tendons out of an estimated total of twelve (12) tendons in the noted beam. The tension deficient tendons have resulted in deflection or sagging of the beam. Measurements across the joint were up to 1-1/2 relative to the newer construction in the center portion. When the magnitude of this deficiency was discovered, the roof section of the west end of the garage was immediately closed and traffic routed away from the deficient beam. The closure remained in place until shoring was installed as discussed below. The installed shoring is a short term solution to the deficiency and should be relied upon for a limited period of time. Refer to the discussion below for specific recommendations. Even with the shoring in-place, additional sagging of the deficient concrete beam adjacent the steel beam shoring has occurred. As a result, traffic was moved away from the middle third of the beam span to reduce loading and the tire impact across the joint. Since the steel beam shoring was installed, the deflection values in the steel beam have been measured and it is currently within expectations of dead load deflection. Continued visual observations of the concrete beam indicate no change since the deficiency was first detected. To address the additional concrete beam sagging, additional vertical supports should be added until comprehensive repairs are performed. Refer to the recommendations below. Recommendation: Restrict all parking in the single bay supported by the shoring. Baseline measurements were obtained on the top of Level 3 slab, bottom of steel beam shoring and top of foundation support. The instrument survey will allow detection of small changes in the existing shored elements. The elevations should be taken every two (2) months minimum. If future measurements indicated continued deflection (sagging), the garage section west of column line W7 should be closed until comprehensive repairs are performed or the west end of the garage decommissioned. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.28

39 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Post tension system evaluation December 7, TEMPORARY SHORING AT W7 EXPANSION JOINT It was determined that the tension deficient beam at the W7 expansion joint resulted in a significant reduction in capacity. The advanced level of deterioration in the concrete beam does not permit a repair process to restore the needed capacity. Based on these restraints, a shoring scheme was designed to relieve load placed on the W7 concrete beam. A vertical shoring element was installed immediately after discovery and the roof level closed. The shoring scheme was designed and installed consisting of concrete foundations placed on the existing slab-on-grade concrete, HSS 4 x 4 and HSS 6 x 6 supporting W10 steel beams placed beneath the existing concrete slab. To address the additional concrete beam sagging, additional vertical supports should be added consisting of HSS 6 x 6 columns down to the existing foundations already installed for the shoring scheme. Although the shoring scheme is designed as temporary, it Is expected that the shoring could remain in place for a period of time until the disposition of the garage is determined but not recommended to extend beyond 2 or 3 years of service or until there are signs of change. The shoring elements and surfaces of the Level 3 slab in the vicinity of the steel beams should be observed monthly for changes in alignment, slab cracking or other deficiencies. Photo 40 Slab-on-grade concrete foundation and HHS 6x6 supporting the slab soffit for HHS and beam above. (December 2015) Photo 41 Level 3 soffit and HHS column and W10 beam placed adjacent deficient beam. gg u:\ \management\report\final\green street parking garage study_final draft.docx 4.29

40 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, REPAIR OPTIONS 5.1 DESCRIPTION The parking garage, approaching 40 years in age, exhibits many deficiencies with the post tensioned slabs and beams. There are other structural deficiencies such as damaged concrete slabs from spalls and delaminations and failure of the cable restraint along the south elevation of Level 2. In summary, the post tension evaluation found the following deficiencies: East end slab P/T cables - test probes found that 6 of 39 (15%) of cables exposed were deficient West end slab P/T cables - test probes found that 4 of 45 (9%) of cables exposed were deficient East end beam P/T cables - test probes found that 5 of 24 (21%) of cables exposed were deficient West end beam P/T cables - test probes found that 11 of 58 (19%) of cables exposed were deficient (Not including column at Column Line W7) In addition, a large number of tendons contained either water or enough moisture to be classified as wet or in the gray zone wet / dry. This sampling represents approximately 25% of the slab tendons and approximately 15% of the beam tendons. For the purpose of this report, the sampling was large enough to apply these percentages to the entire garage. Typically, the preparation of potential options to address structural deficiencies with associated repair programs is highly dependent on the desired future life of the parking garage. Because the damage is so widespread and repairs so intrusive and costly, this garage appears to have limited options. Each repair option must address the widespread structural deficiencies to maintain service. Given the nature of post-tension reinforcing, there is no easy fix to restore capacity. One option considered is to allow the East and West ends of the garage to be decommissioned. Considering that the garage is nearly 40-years in age and operating under severe exposure conditions found in the northeast, it would be overly optimistic to expect that even a large capital repair on the original garage could achieve another 40-years of service. There are too many deficiencies to overcome such as concealed corrosion and high chloride contents in concrete. For the purpose of planning and to allow for gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.30

41 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, 2016 comparison, several options were developed with associated life expectancies based on judgement and experience. A brief discussion of the options and life expectance are generally discussed below: 5-10 YEAR LIFE This is a limited approach to extend the life of the garage for a short period of time. It is considered a bandage to provide continued service until repairs to slabs and beams become so frequent that the structural system is un-reliable YEAR LIFE This approach is similar to the 5-10 year approach except it also applies corrosion protection technology to extend the life of the garage components but these technologies are problematic and may not work in all cases. It is anticipated that the applied technology could extend service until slab and beam repairs again become so frequent that the structural system is un-reliable. 30 YEAR LIFE This approach incorporates a companion structural post tension system for the slabs and is not reliant in the existing reinforcing system. This would allow for the slab tendons to fail without having to maintain and repair. For the purpose of this study, the options considered are as follows: REPAIR OPTION 1 - REPAIR OF BROKEN P/T; ADDEXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS for CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) Repair Option 1 addresses the current deficiencies in the structural capacity of slabs and beams but does not go forward with work to rejuvenate the remaining slab post tension tendons to extend service. Under this Option, tendons will continue to fail and periodic repairs will be needed to repair additional tendons that fail over time. This option is basically a band aide to keep the garage open until demolition and rebuild or demolition to allow other development. REPAIR OPTION 2 - COMPREHENSIVE P/T RESTORATION; ADD EXTERNAL BEAM P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING for CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) Repair Option 2 addresses the current deficiencies in the structural capacity of slabs and beams and using techniques to rejuvenate the remaining slab post tension tendons. Under the Option, there is less probability that tendons will continue to fail. Periodic repairs should be planned over time but will be less frequent. The option also performs comprehensive repairs to structural slabs and replaces the waterproofing system. This option continues to rely on the existing post-tensioning system for continued service. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.31

42 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, 2016 REPAIR OPTION 3 - NEW P/T MINI-BEAMS; ADD EXTERNAL BEAM P/T SYSTEM AND WATERPROOFING for CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) Repair Option 3 addresses the current deficiencies in the structural capacity of slabs and beams by adding new post tension systems to slabs by cutting in and casting posttensioned mini-beams and providing external post-tension system to the mini-beams. The option includes comprehensive repairs to structural slabs and replaces the waterproofing system. This option would not rely on the current P/T system for slabs and beams and the new systems would allow additional slab and beam tendons to fail without the need for action. REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) This option would perform limited structural repairs to allow for the existing east and west ends of the garage to remain open for a period of 2-3 years and provide for the construction of an additional four (4) levels. REPAIR OPTION 4A DECOMISSION EAST END; REPAIR WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR WEST END AND 50+YEARS AT CENTER PORTION) This option would perform limited structural repairs to allow for the existing east end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the West end and construction of an additional four (4) levels to the center portion. REPAIR OPTION 4B DECOMISSION WEST END; REPAIR EAST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+YEARS AT CENTER PORTION) This option would perform limited structural repairs to allow for the existing west end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the East end and construction of an additional four (4) levels to the center portion. REPAIR OPTION 4C REPAIRS TO EAST END AND WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST AND WEST ENDS AND 50+YEARS AT CENTER PORTION) This option would perform comprehensive Option 3 repairs to the East end and West End and construction of an additional four (4) levels to the center portion. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.32

43 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, REPAIR OPTION 1 REPAIR OF BROKEN P/T; ADD EXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS FOR CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) Repair Option 1 addresses the current deficiencies in the structural capacity of slabs and beams. This work can be done with limited interruption to garage operations. Closures and temporary protection can be local to the work areas. The work also includes repairs to the post tensioned beam and column line W7. The structural restoration of slabs to correct spalls and delaminations will be more disruptive and will require shoring and enclosures to contain dust and debris and keep the public away from the repair areas. The Primary work Items include the following: W7 Beam Rebuild The current shoring will remain in place for a period of two or three years until the beam is replaced. The beam could be demolished and re-cast with new posttensioning systems. The work will be disruptive to the existing slab anchors and they would have to be temporarily removed, reset and recast with the beam. Additional slab shoring and enclosures would be required for this work. The beam rebuilding would also require removal of existing precast panels or cutting a portion of the panel to allow for the repair. East and West End: 1. Shoring: Shoring typically will not be required for the piecemeal repair / replacement of the slab tendon cables. Other shoring may be needed for large slab repairs and P/T beam work. 2. Temporary protection: Protection during demolition/repair of the Rothchild s building (occupied by Thompkins Trust), below Level 2, from column lines E1 to E8 (east end) would be needed. It is assumed that the Rothchild s building will be unoccupied for the duration of the repair work. The Level 2 slab is the roof of the building below and additional precautions must be made to protect the space below during demolition activities. Protection might include canopies and other measures. 3. Post-tension slab repairs: This includes replacing/splicing broken or corroded cables, repacking grease and cement grout at anchorages or placing new concrete around stressing anchors. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.33

44 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, Post-tension beam repairs: The cable extraction effort performed by Vector concluded that the extensive cable corrosion makes piecemeal removal and replacement of cables difficult if not impossible. It would be better to augment the existing beam with an external post-tension application. The capacity of the existing beams would have to evaluated followed by installation of high strength steel cables at exterior of beams, rather than attempting to thread new cables inside. The designed exterior post tensioned system should match the lost capacity. The work may require accessing the beam pocket ends by removing panels to expose the beam pockets for the space needed for installation. Use of carbon fiber wraps may also be an option but there are limitations on the capacities that fiber wraps can replace and use is unlikely. 5. Slab repairs: Delamination surveys extrapolates to approximately 1,870 square feet of the deck that is delaminated. The damaged concrete should be repaired to restore slab capacity. Delaminated concrete will be removed down to sound concrete, the steel cleaned and the voids filled with concrete. 6. Barrier strand repairs: The work includes replacing the failed barrier strand along column line H at the south perimeter of the garage with a guard rail system similar to what was installed at the west end to re-establish a compliant barrier restraint. There is concern that the existing precast panels no longer provide a suitable vehicle restraint due to compromised deck attachment. 7. Expansion joint replacement: Replace Level 3 expansion joints at column lines W7-1 and column lines 11-E1. The joints should be addressed to prevent leakage and future damage to the supporting beams. 8. Traffic Bearing Deck Coating: at structural repairs and turning radius at ends: Provide new coating. System at deck repairs and repairs to turning areas at ends of the garage and other areas of poor performance. 5.3 REPAIR OPTION 2 COMPREHENSIVE P/T RESTORATION; ADD EXTERNAL BEAM P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) Repair Option 2 addresses the current deficiencies in the structural capacity of slabs and beams and rejuvenates the remaining slab tendons and available beam tendons. The work includes all work in Repair Option 1 and the additional work as stated below. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.34

45 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, 2016 The Primary work Items include the following: W7 Beam Rebuild See Option 1 East and West End: 1. Shoring: shoring would be similar to Option Temporary protection: Protection would be similar to Option 1 3. Post-tension slab repairs: This includes replacing/splicing broken or corroded cables, repacking grease and cement grout at anchorages or placing new concrete around stressing anchors. Tendons with appropriate tension should be dried and greased. 4. Post-tension beam repairs: Augment the existing beam strength with an external post-tension application similar to Option 1. Available beam tendons with appropriate tension should be dried and greased. 5. Slab repairs: Repair delaminated concrete similar to Option Barrier strand repairs: Replace damaged barrier strands similar to Option Expansion joint replacement: Replace Level 2 and Level 3 expansion joints at column lines W7-1 and column lines 11-E1. Also replace expansion joints between the garage and building stairs and ramps. 8. Traffic Bearing Deck Coating: Remove and replace all traffic bearing coating to existing concrete and repair surfaces. Provide a new heavy duty (drive lanes) and medium duty (parking stalls) urethane deck coating to the entire garage. Less traffic areas such as the parking stalls of the east end could be topcoated. 9. Repair delaminated vertical surface concrete at columns and walls. Remove deteriorated concrete, expose and clean reinforcing, provide corrosion inhibitor and fill chipped out voids with a polymer modified repair mortar. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.35

46 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, REPAIR OPTION 3 NEW P/T MINI-BEAMS; ADD EXTERNAL BEAM P/T SYSTEM AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) Repair Option 3 addresses the current deficiencies in the structural capacity of slabs by adding new post tension system to restore slab capacity and providing external posttension system to beams. This option is highly disruptive and will require shoring and enclosures to contain dust and debris and keep the public away from the repair areas. The work also includes repairs to the post tensioned beam and column line W7. The Primary work Items include the following: W7 Beam Rebuild See Option 1 East and West End: 1. Shoring: will be much more extensive that Options 1 and 2. Shoring down to grade will be required to cut slots in slabs for new P/T beams. Shoring or isolation of the structure for beam repairs. 2. Protection during demolition/repair: will be extensive as cutting slots will be very disruptive. 3. Post-tension mini beams at slabs: This includes cutting in and casting posttensioned mini-beams. The beams will be parallel to the current slab span and will be at roughly 8 feet on center. This approach does not rely on the current slab P/T system. The replacement tendons will employ a fully encapsulated system. 4. Post-tension beam repairs: Augment the existing beam strength with an external post-tension application similar to Option 2 and drying and greasing the remaining beam tendons. 5. Repairs of delaminated and spalled concrete: This work will be similar to Option Replace expansion joint gland: This work will be similar to Option Restore perimeter barrier system where the current system has failed: This work will be similar to Option Traffic Bearing Deck Coating: This work will be similar to Option 2. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.36

47 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, Repair delaminated vertical surface concrete at columns and walls: This work will be similar to Option REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) This option addresses limited structural repairs to allow for the existing east and west ends of the garage to remain open for a period of 2-3 years and provide for the construction of an additional four (4) levels. The garage would be closed for the duration of the work. Temporary egress would have to be provided to the adjacent building using garage as emergency exit. East and West End: Demolition: The work will include addressing existing utilities and demolishing the existing east and west ends of the parking garage including the Thompkins Trust Space. Site Preparation: The work will include site preparation for future development. Add 4 levels to existing center garage: The work will include all of the work for site preparation for future development. 5.6 COMBINED REPAIR OPTIONS Combined repair options were also considered to explore other options that include the reuse of the existing garage and the garage expansion. The combined options only considered Repair Option 3 as a repair scenario as it would not be prudent to invest an expansion of the center section with a lower repair effort (Option 1 and Option 2) for either the East end and West End. Option 3 was combined with the Option 4 (4-story addition to the existing center section). This evaluation looked at both the East end and West end separately to afford a comparison of either the East end or West end. A summary of the parking spaces is based on the information contained in the Renovation drawings for the construction is as follows: gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.37

48 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK repair options December 7, 2016 Number of Parking Spaces for Combined Options Configuration Number of Spaces (Includes Grade Level) Current (East-Center-West sections) 457 Center Expansion (4 levels) 236 Existing East Plus Center Expansion (4 levels) 519 Existing West Plus Center Expansion (4 levels) 517 Existing East and West Plus Center Expansion 689 REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) This option would perform limited structural repairs to allow for the existing east and west ends of the garage to remain open for a period of 2-3 years and provide for the construction of an additional four (4) levels to the existing center portion. REPAIR OPTION 4A DECOMISSION EAST END; REPAIR WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR WEST END AND 50+YEARS AT CENTER PORTION) Option is a combination of Repair Option 3 Repair West end and Option 4. This option would perform limited structural repairs to allow for the existing east end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the West end and construction of an additional four (4) levels to the center portion. REPAIR OPTION 4B DECOMISSION WEST END; REPAIR EAST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+YEARS AT CENTER PORTION) Option is a combination of Repair Option 3 Repair East end and Option 4. This option would perform limited structural repairs to allow for the existing west end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the East end and construction of an additional four (4) levels to the center portion. REPAIR OPTION 4C REPAIRS TO EAST END AND WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST AND WEST ENDS AND 50+YEARS AT CENTER PORTION) This option would perform comprehensive Option 3 repairs to the East end and West End and construction of an additional four (4) levels to the center portion. This option would perform limited structural repairs to allow for the existing east end garage to remain open for a period of 2-3 years, comprehensive Option 3 repairs to the West end and construction of an additional four (4) levels to the center portion. gg u:\ \management\report\final\green street parking garage study_final draft.docx 5.38

49 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, OPINION OF CONSTRUCTION COST 6.1 INTRODUCTION The Opinion of Probably Construction Cost is based on our understanding of the conditions and our experience on similar projects. There are many market and other factors that will impact the Opinion of construction cost. Stantec engaged a specialty contractor to help establish probable costs for common work items. This was the best method unless a construction manager or contractor provided costing. The most useful of the information present is to provide side-by-side comparisons of the different options. Because of the different life expectancies of the options, we could not perform a typical life-cycle analysis. The costing analysis did estimate future maintenance and repair costs to maintain occupancy until the garage or ends will be closed. 6.2 REPAIR OPTION 1 REPAIR OF BROKEN P/T; ADD EXTERNAL BEAM P/T SYSTEM; PEFORM LIMITED REPAIRS FOR CURRENT GARAGE CONFIGURATION (5-10 YEAR LIFE) Opinion of Probable Construction Cost - East End Slabs and Beams Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $1,344,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing $122,000 $70,000 $62,000 General Conditions, Overhead and Profit, Contingency, $1,068,000 Consultant Costs, City/CM Costs TOTAL $2,666,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.39

50 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, 2016 Opinion of Probable Construction Cost West End W7 Beam Rebuild Level 3 Slabs and Beams Shoring; Access; Demolition; Rebuild Beam and Reset Slab Anchors Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $352,000 $1,317,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $64,000 $82,000 $62,000 $1,257,000 TOTAL $3,134,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.40

51 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, REPAIR OPTION 2 COMPREHENSIVE P/T RESTORATION; ADD EXTERNAL P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (15-20-YEAR LIFE) Opinion of Probable Construction Cost - East End Slabs and Beams Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $1,519,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Maintenance at10- Years Maintenance at15- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $224,000 $113,000 $79,000 $228,000 $79,000 $1,503,000 TOTAL $3,745,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.41

52 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, 2016 Opinion of Probable Construction Cost West End W7 Beam Rebuild Level 3 Slabs and Beams Shoring; Access; Demolition; Rebuild Beam and Reset Slab Anchors Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $352,000 $1,491,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Maintenance at10- Years Maintenance at15- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing $157,000 $130,000 $79,000 $284,000 $79,000 General Conditions, Overhead and Profit, Contingency, $1,159,000 Consultant Costs, City/CM Costs TOTAL $4,292,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.42

53 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, REPAIR OPTION 3 NEW P/T MINI-BEAMS; ADD EXTERNAL P/T SYSTEM; STRUCTURAL REPAIRS AND WATERPROOFING FOR CURRENT GARAGE CONFIGURATION (30-YEAR LIFE) Opinion of Probable Construction Cost - East End Slabs and Beams Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $1,965,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Maintenance at10- Years Maintenance at15- Years Maintenance at 20- Years Maintenance at 25- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $224,000 $219,000 $57,000 $206,000 $58,000 $206,000 $85,000 $2,030,000 TOTAL $5,050,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.43

54 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, 2016 Opinion of Probable Construction Cost West End W7 Beam Rebuild Level 3 Slabs and Beams Shoring; Access; Demolition; Rebuild Beam and Reset Slab Anchors Shoring; Temporary Protection, Post-tension Repairs; Add Exterior Slab Post-tensioning and Slab Repairs $352,000 $1,834,000 Other Structural and Waterproofing Work Allowance for Other Work Maintenance at 5- Years Maintenance at10- Years Maintenance at15- Years Maintenance at20- Years Maintenance at25- Years Soft Costs Replacing barrier strand; Expansion joint replacement and limited traffic bearing coating Allowance for stairs, elevators, wayfaring and revenue control; electrical work and plumbing work Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $157,000 $234,000 $79,000 $174,000 $59,000 $206,000 $88,000 $2,146,000 TOTAL $5,329,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.44

55 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, REPAIR OPTION 4 DECOMISSION EAST AND WEST ENDS WITH EXPANSION OF EXISTING CENTER PORTION. (50+-YEAR LIFE) Opinion of Probable Construction Cost Demolish East End Temporary Protection, MP&T and Demolition. $1,170,000 Demolish West End Temporary Protection, MP&T and Demolition. $870,000 Rebuild Center Section Soft Costs Includes Shoring; Temporary Protection, rebuilding slabs an all associated construction, electrical and plumbing work. General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $6,200,000 $5,522,000 TOTAL $13,762, REPAIR OPTION 4A DECOMISSION EAST END; REPAIR WEST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR WEST END AND 50+-YEAR LIFE) Demolish East End Temporary Protection, MP&T and Demolition. $1,170,000 Repair West End See Option 3. $2,580,000 Rebuild Center Section Maintenance at 5 through Yea 25 Soft Costs Includes Shoring; Temporary Protection, rebuilding slabs an all associated construction, electrical and plumbing work. Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $6,200,000 $610,000 $7,069,000 TOTAL $17,629,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.45

56 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, REPAIR OPTION 4B DECOMISSION WEST END; REPAIR EAST END WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+-YEAR LIFE) Demolish East End Temporary Protection, MP&T and Demolition. $870,000 Repair East End See Option 3. $2,410,000 Rebuild Center Section Maintenance at 5 through Yea 25 Soft Costs Includes Shoring; Temporary Protection, rebuilding slabs an all associated construction, electrical and plumbing work. Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing General Conditions, Overhead and Profit, Contingency, Consultant Costs, City/CM Costs $6,200,000 $610,000 $6,764,000 TOTAL $16,854, REPAIR OPTION 4C REPAIRS TO EAST END AND WEST END; WITH EXPANSION OF EXISTING CENTER PORTION. (30 YEAR EAST END AND 50+-YEAR LIFE) Repair East End See Option 3. $2,410,000 Repair West End See Option 3. $2,580,000 Rebuild Center Section Maintenance at 5 through Yea 25 Soft Costs Includes Shoring; Temporary Protection, rebuilding slabs an all associated construction, electrical and plumbing work. Includes Shoring; Temporary Protection, Post-tension Repairs; slab repairs and allowance for electrical work and plumbing $6,200,000 $1,220,000 General Conditions, Overhead and Profit, Contingency, $8,339,000 Consultant Costs, City/CM Costs TOTAL $20,749,000 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.46

57 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Opinion of Construction Cost December 7, COST PER PARKING SPACE FOR OPTION 4 BASED ON 30-YEAR LIFE The cost per space for the different Option 4 scenarios based on the number of parking spaces is as follows: Configuration Option 4 Decommission East and West Plus Center Expansion (4 levels) Option 4A Decommission East & Repair West Plus Center Expansion (4 levels) Option 4B Decommission West and Repair East Plus Center Expansion (4 levels) Option 4C Repair East and West Plus Center Expansion Number of Spaces (Includes Grade Level) Opinion of Cost Cost per Parking Space 236 $13,760,000 $58, $17,630,000 $34, $16,850,000 $32, $20,750,000 $30,100 gg u:\ \management\report\final\green street parking garage study_final draft.docx 6.47

58 GREEN STREET PARKING GARAGE EAST AND WEST END STUDY CITY OF ITHACA, NEW YORK Appendix A Figures December 7, 2016 Appendix A FIGURES FIG 1 GROUND, SECOND AND THIRD FLOOR FIG 2 SECOND FLOOR PLAN WEST - SURVEYS FIG 3 SECOND FLOOR PLAN EAST - SURVEYS FIG 4 THIRD FLOOR PLAN WEST - SURVEYS FIG 5 THIRD FLOOR PLAN EAST - SURVEYS FIG 6 SOUTH ELEVATION WEST SECTION FIG 7 SOUTH ELEVATION MIDDLE SECTION FIG 8 WALL SECTION FIG 9 SECOND FLOOR PLAN WEST OPTION 1 FIG 10 SECOND FLOOR PLAN EAST OPTION 1 FIG 11 THIRD FLOOR PLAN WEST OPTION 1 FIG 12 THIRD FLOOR PLAN EAST OPTION 1 FIG 13 THIRD FLOOR PLAN WEST OPTION 2 FIG 14 SECOND FLOOR PLAN EAST OPTION 2 FIG 15 SECOND FLOOR PLAN WEST OPTION 3 FIG 16 SECOND FLOOR PLAN EAST OPTION 3 FIG 17 SECOND FLOOR PLAN WEST OPTION 4 FIG 18 SECOND FLOOR PLAN EAST OPTION 4 FIG 19 OPTION 4 DEMOLISH ENDS WITH EXANSION OF CENTER SECTION A.1

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110 Post-Tensioned Tendon Evaluation Green Street Parking Garage, Ithaca, New York Prepared For: Stantec Consulting Services Inc. 61 Commercial St, Suite 100 Rochester, New York Attn: Gary Garwig, PE Prepared by: Daniel Rosa, B.Eng. Vector Corrosion Technologies Ltd. January 26, 2016 Innovative Solutions to Concrete Problems

111 Post-Tensioned Tendon Evaluation Green St Parking Garage Ithaca, NY 1.0 INTRODUCTION 1.1 Authorization The post-tensioned tendon inspections were requested by Stantec Consulting Services Inc to the East and West sections of the Green St Parking Garage in Ithaca, NY. The East section inspection was performed in November 2015 while the West section inspection was performed in December Purpose The purpose of the evaluation was to: Determine the extent of tension deficient tendons; Check the quality and quantity of the protective grease within the tendon sheath; Asses the moisture level in the tendon environment (air within tendon sheathing); and Determine the locations of any identified cable deficiencies (where possible). 1.3 Methodology Work completed during the investigations included: Reviewing existing structural drawings; Creating 68 inspection openings by removing concrete around the cable; Visually inspecting the cables and grease for signs of corrosion; Impact testing each cable to determine the degree of tension within the cable; Performed Corrosion Potential Evaluation; Testing the moisture level of the air within the sheath; Extracting broken sections of cables at 2 locations to determine the cause and location of breakage; and Installing plates over inspection openings to allow for periodic testing. 1.4 General Description The Green Street parking structure is a 3-level, post-tensioned (PT) concrete structure constructed in the early 1970s. The upper two slabs are PT reinforced and the bottom slab is on grade. The garage footprint is separated with expansion joints at gridlines 7 and 15 (as per the original structural drawing by T.Y. Lin & Associates), creating East, Center and West sections on the supported levels. The parking garage was originally constructed with a 7.5" thick CIP, PT floor system supported by 18"x36" PT concrete beam. Innovative Solutions to Concrete Problems

112 Post-Tensioned Tendon Evaluation Green St Parking Garage Ithaca, NY 2.0 Key Findings 2.1 The Beam at Gridline 7 (West of the expansion joint) Is Tension Deficient. The beam at Gridline 7 is tension deficient, meaning that the beam can no longer support the loads it was intended to support. We inspected all 9 tendons within this beam location and found that all tendons tested were tension deficient. Cables are deemed tension deficient when the tester is able penetrate the tip of a flat head screwdriver in between the individual wires, that comprise a tendon, with minimal force. The visual inspection also identified that the amount of grease within the sheaths was dry and of insufficient quantity. Poor quality and quantity of grease increases the likelihood of cable corrosion. We were not able to remove any tendons to confirm the cause or location of breakage. Because of the broken tendons, the beam has deflected between 2 to 3 inches over the mid spans that taper to original grade over column supports. Stress cracks were also observed throughout the beam. The number of broken cables, deflection and stress cracking was unique to this beam. 2.2 There Is a High Percentage of Tension Deficient Tendons Within the Test Sample The percentage of tension deficient cables within our test sample is high, which suggests widespread tendon tension issues. The overall percent of tension deficient tendons in the East and West garage sections was 16% (26 of 166 cables tested, not including the beam at Gridline 7). The highest tension deficient percentages were concentrated to the Roof Level of the East Section and Level 2 of the West Section. 2.3 Tendons Have Bulk Water and Evidence of Moisture Within the Cable Sheathing. We observed bulk water or elevated moisture levels in many tendons inspected. Any moisture within the sheath creates an environment for corrosion to occur. A number of cables, where bulk water was observed, showed signs significant corrosion. We observed bulk water in most of the beam tendons evaluated. When bulk water is evident the Corrosion Potential Evaluation (CPE) does not provide any useful information. The CPE testing was used with success on the slab cables where bulk water was less frequent. The moisture levels measured here indicate that the cables fall within the Wet/Dry Zone on our corrosion classification system (see Appendix B). This indicates that corrosion may be occurring. Innovative Solutions to Concrete Problems

113 Post-Tensioned Tendon Evaluation Green St Parking Garage Ithaca, NY Once water is within the sheath, it tends to collect at the low drape points of the tendon, which along with anchor locations is also the most likely location for cable corrosion to occur. We observed this in 2 locations: Cable 6 of beam opening *C as per DWG A / S1 (See appendix A) was extracted and found to be corroded and broken at the low drape of the North span. Cable 2 of Opening *C as per DWG B / S3 which was found broken and severely corroded at the North end anchor. 2.4 All Protective Grease Is Substandard Further contributing to the degradation of the cable systems was the absence of adequate protective cable grease on an overwhelming majority of the cables. All cables contained a combination of emulsified, dehydrated or an inadequate volume of grease. 3.0 Conclusion and Recommendations The garage has a large percentage of broken cables throughout. The breakages tend to be significantly elevated on the Roof Level of the East Garage and Level 2 of the West Garage. These areas should be reviewed by a structural engineer to determine if the slabs and beams are capable of supporting the loads it is intended to support. The large number of broken or tension deficient cables is likely due to the ingress of water into the cable sheaths from the anchor causing corrosion of the tendons. This corrosive activity has been compounded by the insufficient and dry grease. A repair strategy should include removing the existing moisture from the cables, encapsulating the cables with new grease and waterproofing the anchor ends to reduce the risk of water ingress. Trusting you will find the above satisfactory. If you have any questions, you are welcome to contact our office at (905) or myself at danielr@vector-corrosion.com. Respectfully submitted, VECTOR CORROSION TECHNOLOGIES LIMITED Daniel Rosa, B.Eng. PTI Unbonded Post-Tension Inspector # Innovative Solutions to Concrete Problems

114 Appendix A Cable Tension Testing Results Innovative Solutions to Concrete Problems

115 Green St Parking Garage Ithaca, NY Post-Tension Evaluation Innovative Solutions to Concrete Problems

116 GREEN ST PARKING GARAGE - ITHACA, NY POST-TENSION EVALUATION ROOF LEVEL OPENINGS - EAST GARAGE SECTION TENDON DEFICIENCY RESULTS

117 GREEN ST PARKING GARAGE - ITHACA, NY POST-TENSION EVALUATION LEVEL 2 - EAST GARAGE SECTION TENDON DEFICIENCY RESULTS

118 GREEN ST PARKING GARAGE - ITHACA, NY POST-TENSION EVALUATION ROOF LEVEL OPENINGS - WEST GARAGE SECTION TENDON DEFICIENCY RESULTS

119 GREEN ST PARKING GARAGE - ITHACA, NY POST-TENSION EVALUATION LEVEL 2 OPENINGS - WEST GARAGE SECTION TENDON DEFICIENCY RESULTS

120 Appendix B Corrosion Potential Evaluation (CPE) Test Results Innovative Solutions to Concrete Problems

121 Green St Parking Garage Ithaca, NY Post-Tension Evaluation CPE Samples 1- East Garage Section - Roof Level (see Dwg 1) Opening # Deg C %RH Innovative Solutions to Concrete Problems

122 Green St Parking Garage Ithaca, NY Post-Tension Evaluation CPE Samples 2 - East Garage Section - Roof Level (see Dwg 2) No. Deg C %RH Innovative Solutions to Concrete Problems

123 Green St Parking Garage Ithaca, NY Post-Tension Evaluation CPE Samples 3 - West Garage Section - Roof Level (see Dwg 5) Opening # Deg C %RH Innovative Solutions to Concrete Problems

124 Green St Parking Garage Ithaca, NY Post-Tension Evaluation CPE Samples 4 - West Garage Section - Roof Level (see Dwg 6) Opening # Deg C %RH Innovative Solutions to Concrete Problems

125 Green St Parking Garage Ithaca, NY Post-Tension Evaluation CPE Samples 5 - West Garage Section - Level 2 (see Dwg 7) Opening # Deg C %RH Innovative Solutions to Concrete Problems