CITY OF FARMINGTON 800 Municipal Drive Farmington, NM (505) Fax (505)

Transcription

1 CITY OF FARMINGTON 800 Municipal Drive Farmington, NM (505) Fax (505) IMMEDIATE ATTENTION Grading and Drainage Construction for Cottonwood Substation, BID # R ADDENDUM THREE December 27, 2016 Notice to Bidders: The above referenced bid is hereby amended as follows: ADD: Anti-Graffiti Coating, Section (see attached) CHANGE: Bid Proposal, Form AF-3 Replace pages with the attached form CHANGE: Cast-In-Place Retaining Wall, Section Replace pages with the attached specification The following questions or requests for clarification were received regarding this project. Following each question or request for clarification is the response. Q1) Would you consider revising the work hours to include weekends? A1) The working hours will be Monday through Friday 7:00 a.m. to 5:00 p.m. Q2) Where is the closest hydrant and how will the meter be acquired? A2) Construction water shall be coordinated by the Contractor with the City of Farmington Public Works Department. A meter will be installed and will be paid for by the Contractor. Q3) Who is responsible for the construction site survey work? A3) All construction surveying shall be provided by the Contractor to finish grades shown on contract drawings. Final volumes and grades will be checked and confirmed by the FEUS surveyors. Q4) Is fencing required around the perimeter? A4) Construction fencing is not necessarily required; however, all site safety/security shall be the Contractor s responsibility. Q5) Is it possible to get power at the site? A5) Temporary Construction power shall be coordinated and paid for by the Contractor. PURCHASING

2 Receipt of this addendum shall be noted on Form AF-1 (a) in Tab I Bidding Requirements for the above referenced bid. If your bid has already been submitted to this office, and this addendum will affect your bid quote, please contact this office and we will return your bid. Any bids that have been received, and are not requested to be returned will remain in this office unopened until January 4, 2017 at 2:00 p.m. /s/ Emily Milne Emily Milne Buyer ll Phone: (505) Fax: (505) emilne@fmtn.org PURCHASING

3 SECTION ANTI GRAFFITI COATING PART 1 - GENERAL 1.01 SCOPE A. Work shall include furnishing and installing a non-sacrificial, anti-graffiti coating on exposed cast-in-place retaining wall face, as specified herein QUALITY ASSURANCE A. Application shall be performed by an experienced and manufacturer approved applicator in strict accordance with manufacturer s recommendations. At no time shall the number of coats and coverage rates be less than recommended in manufacturer s technical data sheets. B. Manufacturer shall be available to make recommendations specific to project, substrate, coating appearance and cleaning options SUBMITTALS A. Contractor shall submit to the Engineer for his approval, manufacturer s data sheets for installation requirements, application procedures and coverage rates. Upon approval of the Engineer, manufacturer s specifications do thereby become a part of this specification and shall be used as the basis for approval or rejection of work carried out in this Section. B. Prior to commencement of work, applicator shall provide to Contractor estimated quantities of each product required to perform the work outlined herein. C. Contractor shall provide documentation of quantities of each product obtained for the work performed. Such information shall be required prior to job acceptance and final payment PRODUCT DELIVERY AND STORAGE A. Deliver to job site in manufacturer s container, with seals unbroken. Containers shall be properly labeled including product name and ID number. B. Keep material protected from the elements and in original unopened containers to prevent contamination by foreign materials. PART 2 - PRODUCTS 2.01 MATERIALS A. Graffiti resistant coating: Anti-Graffiti Coating is one-component, non-sacrificial, readyto-use siloxane coating that cures with atmospheric moisture and dries to a clear, colorless film. Refer to manufacturer for number of recommended coats. Products to be applied according to manufacturers recommended guidelines for project substrates. B. Rates of coverage and number of coats: Bids will be based on manufacturers minimum coverage rates based on permeability and surface area as indicated on Drawings. For information contact the product manufacturer. PART 3 - EXECUTION 3.01 SURFACE PREPARATION Anti-Graffiti Coating December 2016

4 A. New masonry and cement plaster should be cured for a minimum of thirty (30) days. Moisture content should be no higher than 15% as registered on an electronic moisture meter. Do not apply to surfaces below 40 degrees F or above 90 degrees F. Relative Humidity shall be 95% maximum during application. B. Surfaces shall be structurally sound, dry, clean and free of dust, dirt, grime, oils, scale, rust, silicones, curing compounds, alkali, acid residues, etc APPLICATION A. Follow manufacturer s current instructions at all times. Allow coating to dry and become clear before applying subsequent coats. Achieve a uniform pinhole free, continuous film CLEANUP AND PROTECTION A. During process of work, remove discarded coating materials, cans and rags at end of each workday. B. Protect work of other trades, whether to be coated or not, against damage by coating and finish work. Correct any damage by cleaning, repairing or replacing, and recoating, as acceptable to Architect. END OF SECTION Anti-Graffiti Coating December 2016

5 CITY OF FARMINGTON, NEW MEXICO BID PROPOSAL, FORM AF-3 Grading and Drainage Construction for Cottonwood Substation PROJECT #ELENG BID # R BID OPENING January 4, 2017, 2:00 PM ITEM DESCRIPTION UNIT QTY UNIT PRICE TOTALS 1 Moblization LS 1 $ $ 2 Clearing & Grubbing LS 1 $ $ 3 Site Grading (Site Grading, roadway grading) CY 37,323 $ $ 4 Culvert (30" CMP, CIP) LF 96 $ $ 5 Access Road (subgrade prep, basecoarse, CIP) LS 1 $ $ 6 Rip-Rap Placement SF 7 Retaining Wall (CIP) LS 1,225 $ $ 1 $ $ 8 Guard Rail (1-1/4" Pipe, Two Rail, 42" Tall, CIP) LF 1,156 $ $ 9 SWPPP LS 1 $ $ 10 Conduit & Grounding Items (CIP) LS 1 $ $ 11 Site & Construction Surveying LS 12 Anti-Graffiti Sealer LS CONSTRUCTION TOTAL 1 $ $ 1 $ $ $ CITY OF FARMINGTON FORM AF-3

6 CITY OF FARMINGTON, NEW MEXICO BID PROPOSAL, FORM AF-3 TOTAL OF ITEMS 1 THROUGH 12 INCLUSIVE IN WORDS: THE SUM OF DOLLARS AND CENTS. CITY OF FARMINGTON FORM AF-3

7 SECTION CAST-IN-PLACE RETAINING WALL PART 1 GENERAL 1.01 SUMMARY A. This Section includes furnishing all materials and labor required for the construction of a cast-in-place retaining wall. B. Scope of Work: The work shall consist of furnishing materials, labor, equipment and supervision for the construction of a cast-in-place retaining wall structure in accordance with the requirements of this section and in acceptable conformity with the lines, grades, design and dimensions shown in the project site plans PRICE AND PAYMENT PROCEDURES A. Allowances. No allowance shall be made in the price of the retaining wall for excavation beyond the limits required for retaining wall construction as shown on the project plans. B. Unit Prices. In addition to a lump sum price pursuant to completion of the scope of work described in Part 1.01 of this Section, the General Contractor shall provide a unit price per square foot of vertical wall face that shall be the basis of compensation for up to a ten (10) percent increase or reduction in the overall scope of the retaining wall work. C. Measurement and Payment. 1. The unit of measurement for furnishing the cast-in-place retaining wall system shall be the vertical area of the wall face surface as measured from the top of the footer to the top of the wall. The final measured quantity shall include supply of all material components and the installation of the cast-in-place retaining wall system. 2. The final accepted quantities of the cast-in-place retaining wall system will be compensated per the vertical face area as described above. The quantities as shown on the plans and as approved by the Owner shall be the basis for determination of the final payment quantity. Payment shall be made per square foot of vertical wall face REFERENCES A. Where the specification and reference documents conflict, the Owner s designated representative will make the final determination of the applicable document. B. Definitions: 1. Geotextile a geosynthetic fabric manufactured for use as a separation and filtration medium between dissimilar soil materials. Cast-In-Place Retaining Wall December 2016

8 2. Drainage Aggregate clean, crushed stone placed within and immediately behind the precast modular block units to facilitate drainage and reduce compaction requirements immediately adjacent to and behind the precast modular block units. C. Reference Standards 1. Concrete a. Unless otherwise shown or specified, the work shall conform to the American Concrete Institute Manual of Concrete Practice and the latest revisions of all ACI references. b. ACI 214R-11, Recommended Practice for Evaluation of Compression Test Results of Field Concrete c. ACI 306R-10, Recommended Practice for Cold Weather Concreting d. ACI , Manual of Standard Practice for Detailing Reinforced Concrete Structures e. ACI , Building Code Requirements for Reinforced Concrete f. ACI 347R-14, Recommended Practice for concrete Formwork g. ACI , Recommended Practice for Hot Weather Concreting h. ACI 613R-97, Recommended Practice for Selecting Proportions for Concrete i. AC , Recommended Practice for Measuring, Mixing, and Placing Concrete 2. Geosynthetics a. AASHTO M 288 Geotextile Specification for Highway Applications. b. ASTM D3786 Standard Test Method for Bursting Strength of Textile Fabrics Diaphragm Bursting Strength Tester Method. c. ASTM D4354 Standard Practice for Sampling of Geosynthetics for Testing. d. ASTM D4355 Standard Test Method for Deterioration of Geotextiles e. ASTM D4491 Standard Test Methods for Water Permeability of Geotextiles by Permittivity. 4. Soils a. AASHTO M 145 AASHTO Soil Classification System. b. AASHTO T 104 Standard Method of Test for Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate. c. AASHTO T 267 Standard Method of Test for Determination of Organic Content in Soils by Loss of Ignition. d. ASTM C33 Standard Specification for Concrete Aggregates. Cast-In-Place Retaining Wall December 2016

9 e. ASTM D422 Standard Test Method for Particle-Size Analysis of Soils. f. ASTM D448 Standard Classification for Sizes of Aggregates for Road and Bridge Construction. g. ASTM D698 Standard Test Method for Laboratory Compaction Characteristics of Soil Using Standard Effort. (12,400 ft-lbf/ft). h. ASTM D1241 Standard Specification for Materials for Soil-Aggregate Subbase, Base and Surface Courses. i. ASTM D1556 Standard Test Method for Density and Unit Weight of Soil in Place by Sand-Cone Method. j. ASTM D1557 Standard Test Method for Laboratory Compaction Characteristics of Soil Using Modified Effort. (56,000 ft-lbf/ft). k. ASTM D2487 Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System). l. ASTM D2488 Standard Practice for Description and Identification of Soils (Visual-Manual Procedure). m. ASTM D3080 Standard Test Method for Direct Shear Test of Soils Under Consolidated Drained Conditions. n. ASTM D4254 Standard Test Method for Minimum Index Density and Unit Weight of Soils and Calculation of Relative Density. o. ASTM D4318 Standard Test Method for Liquid Limit, Plastic Limit, and Plasticity Index of Soils. p. ASTM D4767- Test Method for Consolidated-Undrained Triaxial Compression Test for Cohesive Soils. q. ASTM D4972 Standard Test Method for ph of Soils. r. ASTM D6938 Standard Test Method for In-Place Density and Water Content of Soil and Aggregate by Nuclear Methods (Shallow Depth). s. ASTM G51 Standard Test Method for Measuring ph of Soil for Use in Corrosion Testing. t. ASTM G57 Standard Test Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method SUBMITTALS A. Submittals shall be made in accordance with Section , GENERAL REQUIREMENTS. In addition, the following specific information shall be provided: a. Concrete mix design b. Material certificates, manufacturers catalog information test reports, etc. B. Installer Qualification Data. At least 14 days prior to construction, the General Contractor shall submit the qualifications of the business entity responsible for Cast-In-Place Retaining Wall December 2016

10 installation of the cast-in-place retaining wall, the Retaining Wall Installation Contractor, per paragraph 1.06, subparagraph A of this section QUALITY ASSURANCE A. Retaining Wall Installation Contractor Qualifications. In order to demonstrate basic competence in the construction of cast-in-place retaining walls, the Retaining Wall Installation Contractor shall document compliance with the following: 1. Experience. a. Construction experience with a minimum of 10,000 square feet of the proposed cast-in-place retaining wall system. b. Construction of at least three (3) cast-in-place retaining wall structures within the past ten (10) years. 2. Retaining Wall Installation Contractor experience documentation for each qualifying project shall include: a. Project name and location b. Date (month and year) of construction completion c. Contact information of Owner or General Contractor d. Type (trade name) of precast modular block system built e. Maximum height of the wall constructed f. Face area of the wall constructed 1.06 QUALITY CONTROL A. The Owner s Representative and Engineer shall review all submittals for materials, design, and the Retaining Wall Installation Contractor qualifications. B. The Owner shall provide an Inspector to perform review and testing during retaining wall construction. The cost of Inspector shall be the responsibility of the Owner. Inspection shall be continuous throughout the construction of the retaining walls. C. The Owner s designated Inspector shall perform the following duties: 1. Inspect the construction of the cast-in-place structure for conformance with construction shop drawings and the requirements of this specification. 2. Verify that soil or aggregate fill placed and compacted in the retained and compacted retaining wall base conforms to paragraphs 3.03 of this section. 3. Notify the Retaining Wall Installation Contractor of any deficiencies in the retaining wall construction and provide the Retaining Wall Installation Contractor a reasonable opportunity to correct the deficiency. 4. Notify the General Contractor, Owner and Retaining Wall Design Engineer of any construction deficiencies that have not been corrected timely. 5. Document all inspection results. Cast-In-Place Retaining Wall December 2016

11 6. Test compacted density and moisture content of the retained backfill with the following frequency: a. At least once every 1,000 square feet (in plan) per 10-inch vertical lift, and b. At least once per every 18 inches of vertical wall construction. D. The General Contractor s engagement of the Owner s designated Inspector does not relieve the Retaining Wall Installation Contractor of responsibility to construct the proposed retaining wall in accordance with the approved construction shop drawings and these specifications. E. The Retaining Wall Installation Contractor shall inspect the on-site grades and excavations prior to construction and notify the Retaining Wall Design Engineer and General Contractor if on-site conditions differ from the elevations and grading conditions depicted in the retaining wall construction shop drawings DELIVERY, STORAGE AND HANDLING A. The Retaining Wall Installation Contractor shall inspect the materials upon delivery to ensure that the proper type, grade and color of materials have been delivered. B. The Retaining Wall Installation Contractor shall store and handle all materials in accordance with the manufacturer s recommendations as specified herein and in a manner that prevents deterioration or damage due to moisture, temperature changes, contaminants, corrosion, breaking, chipping, UV exposure or other causes. Damaged materials shall not be incorporated into the work. C. Geosynthetic Fabrics 1. All geosynthetic materials shall be handled in accordance with ASTM D4873. The materials should be stored off the ground and protected from precipitation, sunlight, dirt and physical damage. D. Drainage Aggregate and Backfill Stockpiles 1. Drainage aggregate or backfill material shall not be piled over unstable slopes or areas of the project site with buried utilities. 2. Drainage aggregate and/or fill material shall not be staged where it may become mixed with or contaminated by poor draining fine-grained soils such as clay or silt. PART 2 MATERIALS 2.01 CONCRETE MATERIALS A. Concrete 1. Cement shall be ASTM C150, latest revision, Type III (High Early Strength) Cement or Type I/II equivalent strength concrete. 2. Concrete aggregates shall conform to ASTM C 33, latest revision, "Specification for Concrete Aggregates." 3. Coarse Aggregate shall be crushed river rock: clean, hard durable, uncoated particles without flat, round, or elongated pieces. Aggregate shall be free from Cast-In-Place Retaining Wall December 2016

12 deleterious materials and shall conform to ASTM C33-74a. Graduation shall be size #467, 1/2 inch to No Water shall be clean and free from injurious amount of oil, acids, salts, organic, or other deleterious matter. 5. Air-entraining admixture, set-retarding admixture and water reducing admixture are the only admixtures that shall be permitted a. Air-entraining admixtures shall conform to ASTM C260-74, Darex AEA, or neutralized Vensol resin (NVX) b. Water reducing admixture shall conform to ASTM C494-71, Type AD, WRDA, as manufactured by W.R. Grace and Company, or Pozzlith, as manufactured by the Master Builders Company c. Set-retarding admixture shall conform to ASTM C494, Type D, PSI-R PLUS or PSI-300R as manufactured by Gifford-Hill & Company, Inc. 6. Micro-fiber is to be added to the mixture to prevent hair-line cracks 7. Xypex additive shall be permitted for containment foundation pours only B. Reinforcing Steel 1. See Section , CONCRETE REINFORCING C. Form-Facing Materials 1. Smooth-Formed Finished Concrete: Form-facing panels that will provide continuous, true, and smooth concrete surfaces. Furnish in largest practicable sizes to minimize number of joints. a. Plywood, metal, or other approved panel materials. b. Exterior-grade plywood panels, suitable for concrete forms, complying with DOC PS 1, and as follows: 1. High-density overlay, Class 1 or better. 2. Medium-density overlay, Class 1 or better; mill-release agent treated and edge sealed. 3. Structural 1, B-B or better; mill oiled and edge sealed. 4. B-B (Concrete Form), Class 1 or better; mill oiled and edge sealed. 2. Rough-Formed Finished Concrete: Plywood, lumber, metal, or another approved material. Provide lumber dressed on at least two edges and one side for tight fit. D. Form-Release Agent: Commercially formulated form-release agent that will not bond with, stain, or adversely affect concrete surfaces and will not impair subsequent treatments of concrete surfaces. 1. Formulate form-release agent with rust inhibitor for steel form-facing materials. Cast-In-Place Retaining Wall December 2016

13 E. Form Ties: Factory-fabricated, removable or snap-off metal or glass-fiberreinforced plastic form ties designed to resist lateral pressure of fresh concrete on forms and to prevent spalling of concrete on removal. 1. Furnish units that will leave no corrodible metal closer than 1 inch to the plane of exposed concrete surface. 2. Furnish ties that, when removed, will leave holes no larger than 1 inch in diameter in concrete surface. 3. Furnish ties with integral water-barrier plates to walls indicated to receive dampproofing or waterproofing. F. Concrete Material Test 1. Cement from approved sources may be accepted on basis of mill tests and certificates of compliance with specification requirements. Certificates and mill test reports shall be furnished for each mill shipment. Cement not used within four months after date of mill test shall be re-tested and all cement failing to meet the original requirements will be rejected. No cement shall be used without approval of the FEUS. 2. Fine and coarse aggregate may be accepted on basis of prior tests provided certificates of compliance with ASTM C33-74a, and these specifications are furnished. 3. Contractor is responsible for notifying and scheduling for testing services. 4. FEUS shall arrange and pay for material testing services. 5. Retesting due to failed tests shall be at the contractor s expense. G. Concrete Mixes 1. The concrete mixes shall have a 3 to 5 inch design slump and a water/cement ratio not to exceed 0.53 by weight, unless noted otherwise in these specifications. (ASTM C143, CSA, A23, 2.20). 2. The compressive strength of the concrete mixes shall test a minimum of 3,500 psi in 28 days. 3. Concrete mix designs shall be submitted for approval by the engineer prior to acceptance by FEUS I. Quality Assurance (Testing Contractor) 1. Prior to placing concrete, a sample is to be tested for slump. The slump of the concrete shall be 3 to 5 inch design, and a water/cement ratio not to exceed 0.53 by weight, unless noted otherwise in these specifications (ASTM C143, CSA, A23, 2.20). FEUS testing contractor shall provide slump tests as provided herein. 2. A minimum of three test cylinders is to be taken from every other concrete truck arriving each day. Cast-In-Place Retaining Wall December 2016

14 a. Testing contractor shall be responsible for furnishing and making all test cylinders and provide all compressive strength tests. The tests shall be performed by a reputable testing laboratory approved by FEUS. b. The test cylinders shall be labeled to match the foundation the sample was taken from. A copy of all test results shall be sent to FEUS, T&D Services, and the Contractor in a timely manner. c. Specimens shall be tested according to Method of Test for Compressive Strength of Molded Concrete Cylinders (ASTM C39, CSA, A23, 2.13). 3. At commencement of work and thereafter, concrete shall be sampled in accordance with Method of Sampling Fresh Concrete (ASTM C172, CSA, A23, 2.21). J. Concrete Proportions and Consistency 1. The proportions of the concrete shall produce a mixture that will work readily, with the placement method used, into corners and angles of forms and around reinforcement. Segregation of materials in the mixture shall not be permitted nor shall collection of excess free water on the surface be permitted. 2. The air content of air-entrained concrete shall be 5 percent by volume plus or minus 1 percent. 3. The methods of measuring concrete materials shall permit proportions to be accurately controlled and easily checked. 4. Measurement of material for ready mixed concrete shall conform to Specifications for Ready-Mixed Concrete (ASTM C94, CSA, A23.1 Clauses 11 and 13). K. Concrete Test During Construction 1. The FEUS testing contractor shall make slump tests; prepare and cure the concrete test cylinders. The FEUS testing contractor shall arrange for pick-up, delivery, testing and maintaining of records for the test cylinders. Copies of all records shall be furnished to FEUS. 2. Cylinders shall be made and cured according to ASTM C31-69 and tested according to the ASTM C (See Quality Assurance Section F) 3. A minimum of three cylinders shall be prepared from every other concrete truck arriving at the job site. If only one truck is to arrive in a single day then cylinders shall be prepared from that truck. a. Location of concrete batches from which concrete test cylinders are made shall be recorded and kept on file at the job until the completion of the work. b. Sampling shall be done in accordance with ASTM C c. One cylinder shall be tested at 7 days, one at 14 days and one at 28 days. i The 7-day tests shall show a compressive strength of at least 75 percent of the specified 28th day strength. Cast-In-Place Retaining Wall December 2016

15 ii If the 14-day test meets or exceeds the required compressive strength of 3500psi, the 28 day test will not be required for that batch. iii The FEUS testing Contractor shall be responsible for the cost of testing the concrete test cylinders. 4. The concrete strengths, as indicated by compression test cylinders, shall have a coefficient of variation of not more than 1 in 10 when referred to a cumulative record for the job. Should these conditions not be met or if FEUS suspects deficient construction, core tests may be required. Cost of cores and tests shall be paid for by the FEUS testing contractor when concrete is deficient. If concrete is not deficient these costs will be paid by FEUS 5. If core test results fall below the design strength specified, concrete represented by the weaker strength samples shall be removed and replaced. Changes shall be made in the mixture or water content for future batches as required by FEUS. All of this shall be accomplished at no additional cost to FEUS. 6. Slump tests for checking consistency of concrete mixture may be made for each set of test cylinders in accordance with ASTM C If conducted by the Owner, field test for air content of air-entrained concrete shall be made for each set of test cylinders and shall conform to requirements of ASTM C Sieve Analysis: Samples of fine and coarse aggregate will be taken by the concrete manufacturer to determine compliance with specifications. L. Mixing of Concrete 1. Ready-mixed concrete shall be mixed and delivered in accordance with the "Specifications for Ready-Mixed Concrete" (ASTM C94, CSA A23.1, Clauses 12 and 13) 2. The temperature of all concrete mixes must be maintained between 50 degrees Fahrenheit and 90 degrees Fahrenheit prior to concrete placement. 3. Cause for Rejection: Failure to comply with any of these concrete specifications is cause for rejection by the Owner. M. Preparation for Concrete Placement 1. Before placement, all equipment for mixing and transporting the concrete shall be cleaned, and all debris and ice shall be removed from the places to be occupied by the concrete. 2. Water shall be removed from place of deposit before concrete is placed. All unsound material shall be removed from concrete before concrete is added. 3. Forms shall be provided for all concrete work. 4. Forms shall conform to the shape, lines, and dimensions of the members indicated on the drawings and shall be substantial and tight to prevent leakage of mortar. They shall be properly braced or tied together to maintain position and shape. Cast-In-Place Retaining Wall December 2016

16 5. Forms for exposed concrete surfaces shall produce a clean smooth surface of uniform texture. Exposed concrete surfaces shall be smooth and free of all honeycomb, defects, etc. All defects due to forms shall be corrected by the contractor prior to application of anti-graffiti coating. Exterior exposed concrete shall be formed with new forming material. 6. Exposed corners of piers shall be chamfered by approved moldings placed in the forms. Lumber once used in forms shall have nails withdrawn, and the surfaces to be exposed to concrete shall be carefully cleaned before reuse. 7. No wire or strap ties shall be permitted. Ties shall be broken off approximately one inch from concrete surfaces. Ties shall be of sizes and weights as required for pressures developed and installed in accordance with manufacturer's recommendations. 8. Prepare forms with release agent. N. Tolerance For Formwork 1. Formwork for concrete shall be set and maintained to ensure completed concrete work within tolerance limits as follows: 2. Top of concrete of a set of foundations at any one tower shall not differ from the specified reference elevation by more than 1/2 inch, and the difference of the tops of concrete between individual foundations shall not differ by more than 1/4 inch. 3. Variation in cross-sectional dimensions of piers and beams shall not exceed minus 1/2 inch or plus 2 inches. O. Preparation for Placing Concrete 1. Water shall be removed from excavations before depositing concrete. Any surface water flow shall be diverted through proper side drain to prevent washing over freshly deposited concrete. Hardened concrete, ice, frozen earth, loose earth, debris and foreign materials shall be removed from form interiors, excavations and conveying equipment inner surfaces. 2. Runways for wheeled equipment (wheel barrows, for instance) shall not be supported on reinforcement. Excavations to receive concrete shall be maintained free of, loose soil, debris and other foreign material prior to placing concrete. 3. It is the responsibility of contractor to ensure that forms, reinforcing and all embedded items are placed to the proper lines, grades and positions, per drawings. 4. No construction joints or cold joints will be allowed, except in unavoidable circumstances and authorized by FEUS and the Manufacturer. If such should occur, FEUS and the Manufacturer shall determine if it is necessary to seal the joint. 5. If the joint is to be sealed, then it shall be sand blasted to expose the aggregate and create a rough surface. The sand blasting material and laitance shall be Cast-In-Place Retaining Wall December 2016

17 thoroughly cleaned from the surface of the concrete. Immediately prior to concrete placement on the existing concrete, a rich cement and sand slurry shall be poured over the joint to cover the entire surface. P. Placing of Concrete 1. Equipment for chuting, pumping, and pneumatically conveying concrete shall be of such size and design as to ensure a practically continuous flow of concrete at the delivery end without separation of materials. 2. Concrete shall be conveyed to point of deposit over runways or by other means without wheeling equipment over reinforcement or fresh concrete. 3. Concrete shall be conveyed rapidly from mixer to forms without segregation or loss of ingredients. Concrete shall be placed in forms near final position to avoid re-handling. Vibrators may be used minimally to transport concrete within forms, but to avoid separating the aggregate from the cement. 4. Placing concrete shall be carried on at such a rate that the concrete is at all times plastic and flows readily into the spaces between the bars. 5. Concrete that has partially hardened or been contaminated by foreign materials shall not be deposited on the work, nor shall re-tempered concrete be used. 6. Immediately after depositing, concrete shall be compacted by agitating thoroughly to force out air pockets by use of a vibrator. Mixtures shall be worked into corners around reinforcement and inserts to prevent formation of voids, i.e. no honeycomb. 7. Care shall be exercised in use of vibrator to prevent segregation, sand pockets, or bleeding. Vibrator shall be moved continuously in and out of concrete, keeping stationary only a few seconds in any position. 8. Concrete shall not "free fall" more than two (2) feet at any time to minimize segregation. A tremie, hopper, trucks, chutes, or pump truck shall be used to minimize free fall. 9. The dropping of the concrete shall be so directed that it will not hit any foreign material such as rebar steel, concrete forms, side of excavation, etc., during its free fall. Chutes, if used, must slope sufficiently to ensure flow of properly prepared concrete. 10. When concreting is once started, it shall be carried on as a continuous operation until the placing of the section is completed. 11. Adjacent concrete surfaces, fresh or cured, shall be protected from concrete drippings, spillage, or splashes. Splattered surfaces shall be cleaned immediately. 12. No concrete placement shall take place during rain. If rain occurs during placement, the Contractor shall keep water out of the excavation and off freshly placed or troweled concrete. Q. Hot Weather Requirements Cast-In-Place Retaining Wall December 2016

18 1. The maximum temperature of mixed concrete shall be 90 F. Temperature of aggregates and mixing water shall be reduced by the use of chilled water or ice. Recommendations in ACI 605 shall be followed. 2. On hot dry days, loss of moisture by evaporation during finishing shall be prevented by erecting sun shades, wind barriers, or water fog sprays or use of a retardant in the mix. R. Cold Weather Requirements 1. Adequate equipment shall be provided for heating the concrete materials and protecting the concrete during freezing or near freezing weather. All concrete materials and all reinforcements, forms, fillers, and ground with which the concrete is to come in contact shall be free from frost. No frozen materials or materials containing ice shall be used. 2. Concrete, after placing shall be kept at a minimum temperature of 50 F for the required curing period. Recommendations in ACI 306 shall be followed. 3. Concrete damaged by freezing shall be removed and replaced under this section of the Specifications. 4. Use of and wrapping of freshly placed concrete with insulating blankets is acceptable if temps drop below 32 deg F. S. Concrete Curing 1. Curing period shall continue until the cumulative number of days or factions thereof, not necessarily consecutive, during which temperature of the air in contact with the concrete is above 50 F, has totaled 7 days for Type I cement and 3 days for Type III cement. Rapid drying at the end of the curing period shall be prevented. 2. To ensure proper hydration of the cement on exposed surfaces, curing shall begin as soon as possible after finishing. In no case shall curing be delayed until the next morning. Curing shall continue for the required period for the cement type used. The curing may be accomplished by either the use of water proof sheets, or membrane forming compound or other approved methods. 3. Joints of waterproof sheets (paper or plastic) must be overlapped at least 4 inches and sealed by continuous tape. Sheets shall be covered with tarpaulins and adequate weights shall be placed to prevent billowing in the wind. 4. Membrane forming compounds may be applied by hand operated or power equipment. Complete coverage is essential. The compound must be applied in two coats with one placed at right angles to the other. If rains occur within 3 hours of application, a new coat must be applied. It will be permissible to apply the second coat the next morning. These compounds shall not be used on any surface that is to receive any coating, covering, or finish, or where additional concrete or other cement-like materials are to be bonded. Only a clear resin based or clear acrylic based curing compound will be acceptable. Cast-In-Place Retaining Wall December 2016

19 5. When forms are left in contact with the concrete for the required curing period, and are exposed to the sun when temperatures exceed 75 degrees, they shall be kept continuously wet. If the forms are to be removed during curing period, one of the curing methods specified in paragraph 4 above shall be continued for the remainder of the curing period. 6. When forms are left in contact with the concrete for the required curing period, and are shielded from the sun, no additional curing effort is required. If the forms are to be removed during the curing period one of the curing methods specified in paragraph 4 above shall be continued for the remainder of the curing period. T. Removal of Forms 1. Forms shall not be disturbed until the concrete has adequately hardened and until the member supported has acquired sufficient strength to safely support its own weight along with the load imposed on it. Wood forms and all particles of wood shall be completely removed (through temporary openings if necessary) to ensure that no material will be left for termite infestation. 2. Tie rod clamps may be loosened 24 hours after concrete is placed. Form ties, except for a sufficient number to hold the forms in place, may be removed at that time. Under normal conditions, the forms will be removed 24 hours after the foundation has been poured. 3. Finish, repair and curing of the formed surfaces shall be completed the same day the forms are removed GEOTEXTILE A. Nonwoven geotextile fabric shall be placed as indicated on the retaining wall construction shop drawings. Additionally, the nonwoven geotextile fabric shall be placed in the v-shaped joint between adjacent block units on the same course. The nonwoven geotextile fabric shall meet the requirements Class 3 construction survivability in accordance with AASHTO M 288. B. Preapproved Nonwoven Geotextile Products 1. Mirafi 140N (or approved equal) 2.03 DRAINAGE AGGREGATE A. Drainage shall be a durable crushed stone conforming to No. 57 size per ASTM C33 with the following particle-size distribution requirements per ASTM D422: U.S. Standard Sieve Size % Passing 1-½ ½ No No Cast-In-Place Retaining Wall December 2016

20 PART 3 EXECUTION 3.01 GENERAL A. All work shall be performed in accordance with OSHA safety standards, state and local building codes and manufacturer s requirements. B. The General Contractor is responsible for the location and protection all new conduit and grounding materials, as shown on sheet series CW-50X, proposed for installation in the vicinity of the retaining wall and shall be installed concurrent with retaining wall construction. The General Contractor shall coordinate the work of subcontractors affected by this requirement. C. New conduit installed below the retaining wall shall be encased with 2000 PSI concrete and backfilled to grade with 120 PSI flowable fill. D. The General Contractor is responsible to ensure that safe excavations and embankments are maintained throughout the course of the project. E. All work shall be inspected by the Owner s designated Inspector as directed by the Owner EXAMINATION A. Prior to construction, the General Contractor, Grading Contractor, Retaining Wall Installation Contractor and Owner s designated Inspector shall examine the areas in which the retaining wall will be constructed to evaluate compliance with the requirements for installation tolerances, worker safety and any site conditions affecting performance of the completed structure. Installation shall proceed only after unsatisfactory conditions have been corrected PREPARATION A. Fill Soil. 1. The Owner s designated Inspector shall verify that any fill soil installed cast-inplace retaining wall footer satisfies the specification of the Retaining Wall Design Engineer as shown on the construction drawings. B. Excavation. 1. The Grading Contractor shall excavate to the lines and grades required for construction of the cast-in-place retaining wall as shown on the construction drawings. The Grading Contractor shall minimize over-excavation. Excavation support, if required, shall be the responsibility of the Grading Contractor. 2. Over-excavated soil shall be replaced with compacted fill in conformance with the specifications of the Retaining Wall Design Engineer and Section Excavation & Fill of these project specifications. C. Foundation Preparation. 1. Prior to construction of the cast-in-place retaining wall, the leveling pad area and undercut zone (if applicable) shall be cleared and grubbed. All topsoil, brush, frozen soil and organic material shall be removed. Additional foundation soils found to be unsatisfactory beyond the specified undercut limits shall be Cast-In-Place Retaining Wall December 2016

21 undercut and replaced with approved fill as directed by the project Geotechnical Engineer. The Owner s designated Inspector shall ensure that the undercut limits are consistent with the requirements of the project Geotechnical Engineer and that all soil fill material is properly compacted according project specifications CAST-IN-PLACE RETAINING WALL INSTALLATION A. The cast-in-place retaining wall structure shall be constructed in accordance with the construction drawings and these specifications. B. Drainage components. Drainage aggregate shall be installed as shown on the construction shop drawings BACKFILL PLACEMENT A. Backfill material placed immediately behind the drainage aggregate shall be compacted as follows: 1. 98% of maximum dry density at ± 2% optimum moisture content per ASTM D698 standard proctor or 85% relative density per ASTM D4254. B. Compactive effort within 3 of the back of the cast-in-place retaining wall should be accomplished with walk-behind compactors. Compaction in this zone shall be within 95% of maximum dry density as measured in accordance with ASTM D698 standard proctor or 80% relative density per ASTM D Heavy equipment should not be operated within 3 of the back of the cast-in-place wall. C. Backfill material shall be installed in lifts that do not exceed a compacted thickness of 9. D. At the end of each work day, the Retaining Wall Installation Contractor shall grade the surface of the last lift of the granular wall infill to a 3% ± 1% slope away from the precast modular block wall face and compact it. E. The General Contractor shall direct the Grading Contractor to protect the cast-inplace wall structure against surface water runoff at all times through the use of berms, diversion ditches, silt fence, temporary drains and/or any other necessary measures to prevent soil staining of the wall face, scour of the retaining wall foundation or erosion of the backfill or wall infill OBSTRUCTIONS IN THE BACKFILL A. The Retaining Wall Installation Contractor shall make all required allowances for obstructions behind and through the wall face in accordance with the approved construction shop drawings. B. Should unplanned obstructions become apparent for which the approved construction shop drawings do not account, the affected portion of the wall shall not be constructed until the Retaining Wall Design Engineer can appropriately address the required procedures for construction of the wall section in question COMPLETION Cast-In-Place Retaining Wall December 2016

22 A. The General Contractor shall confirm that the as-built cast-in-place retaining wall geometries conform to the requirements of this section. The General Contractor shall notify the Owner of any deviations. END OF SECTION Cast-In-Place Retaining Wall December 2016