ASHE NATIONAL PROJECT OF THE YEAR SR 0136-G10 ABC BRIDGE REPLACEMENT in Eighty Four, PA For the PENNSYLVANIA DEPARTMENT OF TRANSPORTATION Engineering District 12-0 Submitted By: January 29, 2018
AMERICAN SOCIETY OF HIGHWAY ENGINEERS National Project of the Year Award OFFICIAL ENTRY FORM AWARD CATEGORY (Check One): Under $20 Million Over $20 Million SPONSORING REGION (Check One): Northeast Mid-Atlantic Southeast Great Lakes North Central South Central Northwest Rocky Mountain Southwest CONTACT INFORMATION FOR SPONSORING REGION: Primary Contact Name: ASHE Region Position: Phone (Office): Phone (Mobile): E-Mail Address: Secondary Contact Name: ASHE Region Position: Phone (Office): Phone (Mobile): E-Mail Address: PROJECT INFORMATION (From Section Entry): ENTERING AGENCY/COMPANY S NAME: PROJECT NAME: PROJECT LOCATION: CITY: CONSTRUCTION COST: PROJECT COMPLETION DATE: TYPE: COUNTY: BUDGETED CONSTRUCTION COST: PROJECT OWNER: STREET ADDRESS: CITY: STATE: ZIP: PHONE: FAX: CONTACT PERSON: E-MAIL ADDRESS: PROJECT DESIGN FIRM: STREET ADDRESS: CITY: STATE: ZIP: PHONE: FAX: CONTACT PERSON: E-MAIL ADDRESS: PRIME CONTRACTOR: STREET ADDRESS: CITY: STATE: ZIP: PHONE: FAX: CONTACT PERSON: E-MAIL ADDRESS: Entry Form Completed By: Date:
Project Description: CDR Maguire Inc. (CDR-M) was retained by PennDOT District 12-0 to design the SR 0136-G10 Bridge Replacement in Eighty Four, Washington County, PA. CDR-M provided project design engineering, environmental permitting, railroad and utility coordination, public/community outreach, and construction consultation services. Subconsultants included American Geotechnical & Environmental Services for Geotechnical Design, ARROW Land Solutions for Right-of-Way Acquisition, and Monaloh Basin Engineers for Survey. This project replaced a 70-year-old structurally deficient 4-span bridge. The replacement structure is a 2-span continuous, 206-foot-long steel multi-girder bridge supported on integral abutments and a pier which carries three lanes of SR 0136 over Little Chartiers Creek and the B&O (CSX) Railroad. The bridge was raised 2 feet to meet current vertical clearance requirements over the railroad. Because of high traffic volumes and lengthy detour, the bridge was designed and constructed using Accelerated Bridge Construction (ABC) methods resulting in a detour duration of just 24 days. Complexity: If this bridge was constructed using conventional methods, it would have been of nominal complexity for a 2-span steel plate girder bridge. However, the use of ABC introduced several complexities that needed addressed to ensure a successful project: Deflections: The girder camber and deck deflection during precasting needed to be considered to ensure that the field splices could be assembled at the site. Field Splices: Access to the tops of the girders for assembly of the field splices needed to be provided. Precise Fabrication: Grouted splice couplers used to connect the various precast elements provided very little fabrication tolerance for fitment. Foundations: Working adjacent to the existing pier and abutment foundations while avoiding interference with existing piles or compromising the integrity of the existing pier was critical. Site Restrictions: The site boundaries were very tight, limiting the room to work without exceeding environmental permit constraints. Crane Sizing: Heavy pick weights with long reaches over a creek and a railroad required a large crane. The contractor used a 650-ton Manitowoc VPC crawler crane located near the pier which enabled him to erect the entire bridge with a single crane. New Application of Existing Techniques / Originality / Innovation: The SR 0136-G10 Bridge Project is the first 2-span continuous bridge replacement constructed using ABC in Pennsylvania. ASTM A709-Grade 50W Weathering Steel Plate girders were paired up and a lightweight composite precast concrete bridge deck was cast onto them to form Prefabricated Bridge Units (PBUs). SR 0136-G10 ABC Bridge Replacement Page 1 of 3
Three PBUs were connected using bolted field splices between the positive and negative moment regions to create two 103-foot-long continuous spans. This eliminated the need for a link slab or transverse joint at the pier. Four sets of PBUs formed the full bridge width. To access the field splices for bolting, a 4-foot gap was provided in the deck. Precast concrete infill panels were used to fill these gaps. Ultra High-Performance Concrete (UHPC), with a compressive strength of approximately 21 ksi, was used in the longitudinal and transverse closure pours to connect the PBUs and infill panels. Precast concrete approach slabs were used and connected using UHPC. An epoxy overlay was then applied over the superstructure. The superstructure is supported on integral abutments and a 3-column pier. The integral abutments, wingwalls, cheekwalls, and backwalls utilized precast concrete for quick assembly at the site. The abutment caps were formed with 30 diameter sleeves to accommodate the piles that were driven prior to assembly. These sleeves were then grouted, and the rest of the elements connected to the abutment cap using grouted splice couplers. The pier foundation was cast-in-place under the existing bridge prior to demolition. The proximity of the new pier foundation to the existing pier created some concerns. A layer of claystone required the bottom of the new pier foundation to be approximately 16 feet below the foundation of the existing pier. Opening a large excavation this deep adjacent to the existing pier while under live traffic would negatively affect the integrity of the existing pier. Extensive shoring was considered. However, limited work space between the creek, the existing pier, and the railroad proved to be prohibitive. As a solution, a series of 60 diameter drilled caissons with steel shells were constructed in a tight pattern. This allowed for the foundation bearing loads to be transferred to bedrock without opening a large, unsupported excavation next to the existing pier. Once the caissons were completed, the cast-in-place spread footing and pier shaft section were poured with the top of shaft set at one foot above the 100-year flood elevation. Once the existing bridge was closed and demolished, the pier was completed using precast concrete columns, cap, and beam seats. Similar to the integral abutments, the pier elements are connected together using grouted slice couplers. Social/Economic Considerations and Safety: The use of ABC on this project provided significant benefits. While ABC typically averages about 20% higher cost than conventional construction, this cost is more than offset by the savings in road user costs. The Road User Liquidated Damages for this project amounted to $50,000 per day based on the traffic volume and detour length. Assuming this project would require 6 months of detour for conventional construction, versus 1 month for ABC, there is a savings of 5 months or approximately 150 days. This amounts to $7.5M. Alternatively, with an ADT of approximately 5,000 vehicles per day traveling a 13 mile detour route, this amounts to an extra 65,000 miles per day or 9.75 million miles over the 5 months extra construction duration. With a 20 mpg average and gasoline cost at $2.50 per gallon, the use of ABC on this project saved the traveling public $1.22M in fuel costs alone. This cost does not even account for wear and tear on the vehicles or lost time it takes to travel the extra 13 miles every day. The project also provided direct benefits by way of improvements in the function of the transportation system locally. The new bridge allowed for the lengthening of the center left turn lane at the signalized intersection with SR 0519 350 east of the bridge. It also raised the vertical clearance over the railroad to meet current SR 0136-G10 ABC Bridge Replacement Page 2 of 3
criteria. Because it was designed to current standards, the bridge is safer due to details such as current barrier details and protective fencing over the railroad. Aesthetics and Sustainable Features: While the project did not warrant any special aesthetic details, a sustainable design that minimized future maintenance was prioritized. Integral abutments and a continuous span design resulted in a jointless superstructure. High quality precast concrete elements and UHPC closure pours ensure a long service life while weathering steel for the girders and cross frames eliminates the need for painting or other coatings. And finally, the girder lines are arranged in a manner that considers future re-decking schemes that minimize impacts to traffic. Meeting and Exceeding /Owner Needs: As described above, the use of ABC increased the project cost over conventional construction. The bids were about 24% higher than the engineer s estimate. The total budgeted cost was $7.1M while the project actual cost was $8.8M. Several factors are believed to have contributed to the increased cost. The project was in competition with PennDOT s ongoing P3 Rapid Bridge Replacement project for materials procurement and fabrication. Additionally, because the amount of time between the project letting and the required start date was short, a premium was paid to meet the aggressive schedule. Also, the unlimited $50,000 per day disincentive cost may have lead the contractor to build in costs to offset the risk of running over schedule. PennDOT has not done many ABC projects, resulting in minimal item price history to adequately predict costs. As more projects are constructed using ABC, it is anticipated that costs will lower and become more predictable due to increased comfort and competition between contractors, suppliers, and fabricators. Dedication to teamwork, communication, and coordination by all parties ultimately resulted in a successful project. Clear contract documents and details and timely reviews allowed the contractor and his fabricators to quickly develop shop drawings to advance procurement of materials and fabrication to meet the aggressive schedule. Detailed reviews, attention to detail, and tight tolerances during fabrication ensured proper fitment of the elements in the field, avoiding delays. Because of everyone s efforts, the project was completed on September 30, 2016 in just 24 days of detour duration 4 days ahead of the scheduled deadline of October 4, 2016. Summary: The SR 0136-G10 Bridge Replacement Project is a significant project for a variety of reasons. It was the first 2-span continuous bridge replacement designed and built using ABC methods in Pennsylvania. The use of ABC introduced unique challenges including critical detailing to ensure fit, integral abutment and pier foundation design to accommodate the existing structure, and crane sizing to construct the project. The entire team, from the owner (PennDOT), the consultant (CDR Maguire), and the contractor (Brayman Construction) were committed to the success of the project. This resulted in the project being completed ahead of an already very aggressive schedule. Therefore, CDR Maguire believes this project is worthy of recognition. SR 0136-G10 ABC Bridge Replacement Page 3 of 3
Photo 1: Longitudinal Reinforcing at Girder Field Splice SR 0136-G10 ABC Bridge Replacement Page 1 of 5
Photo 2: Cast-In-Place Pier Shaft Section Construction under Existing Bridge SR 0136-G10 ABC Bridge Replacement Page 2 of 5
Photo 3: Erected Precast Pier Columns and Bent with Adjacent Temporary Towers SR 0136-G10 ABC Bridge Replacement Page 3 of 5
Photo 4: Span 2 Deck Module Erection with Erected Negative Moment Region SR 0136-G10 ABC Bridge Replacement Page 4 of 5
Photo 5: Filler Panel and Transverse Closure Pours Over Field Splice SR 0136-G10 ABC Bridge Replacement Page 5 of 5
STATEMENT OF COMMITMENT: CDR Maguire Inc. commits that at least one representative of the project team will attend the awards luncheon. SR 0136-G10 ABC Bridge Replacement Page 1 of 1