Advanced Construction Techniques

Transcription

1 Alaskan Way Viaduct Replacement Program Organization University of Washington Date October 20, 2011 Presentation Overview SR 99 south end viaduct replacement. Design-build contracting. SR 99 tunnel project. Construction partnering. Disputes Review Board. Fall Quarter

2 WSDOT Coordination Washington State King County WSDOT Port of Seattle City of Seattle Program History Nisqually earthquake damages viaduct. Draft EIS analyzes five alternatives. Supplemental Draft EIS analyzes two alternatives. No/no advisory vote leads to new approach. Governor signs bill endorsing bored tunnel alternative. Supplemental Draft EIS analyzes bored tunnel. Final EIS and Record of Decision issued. Public process Fall Quarter

3 Program Overview The Alaskan Way Viaduct Replacement Program includes projects led by the Washington State Department of Transportation, City of Seattle, King County and Port of Seattle. Public process Building the New SR 99 Corridor S. Holgate Street to S. King Street Project SR 99 Tunnel Project Fall Quarter

4 South Holgate to South King Street Project Before construction December 2013 STAGING AREA CONTINUING CONSTRUCTION Roadway will be complete in SR 99 remains open during construction. Viaduct s south end will be demolished beginning in October Building the SR 99 Construction Bypass Fall Quarter

5 Demolition Time Lapse Video Realigned SR 99 On- and Off-ramps Fall Quarter

6 Building the SR 99 Roadway Foundation Building Pier Shafts Fall Quarter

7 Driving Piles for the New SR 99 Roadway Piles for the New SR 99 Roadway Fall Quarter

8 Constructing Rebar Cages Building the New SR 99 Roadway Fall Quarter

9 Supporting the New SR 99 Roadway Geofoam Embankment Public process Fall Quarter

10 SR 99 Today Maintaining Traffic During Construction Fall Quarter

11 Changes to SR 99 After the Closure What is Design-Build Contracting? Design-Build ild a method of project delivery in which h the owner executes a single contract with one entity (the Design- Builder) for design and construction services to provide a finished product. VS. Design-Bid-Build traditional approach for delivery of transportation projects where the owner completes the design and accepts the lowest responsive bid for construction from qualified contractors. Fall Quarter

12 Design-Build Legislation History 1998, WSDOT authorized to complete design-build contracting pilot project. 2001, Design-build contracting authorized for use on transportation projects more than $10 million. 2006, WSDOT authorized to pilot up to five projects between $2 and $10 million. 2007, Expiration date deleted from RCW I-405 Kirkland Nickel Stage 1. Design-Build Considerations Time Allows construction to start without final design of all project elements. Design is tailored to contractors means and methods. Generally leads to earlier completion date Budget Requires fewer owner staff. Can lead to earlier cost certainty. Errors and omissions not owner s responsibility. Additional risk is assigned to contractor. Fall Quarter

13 Comparison of Contracting Approaches Typical design-bid-build process Environmental analysis and preliminary design NEPA complete 100% design and permits Typical design-build process Environmental analysis and preliminary design NEPA complete Procurement Begin construction Permits NTP Accelerated design-build ild process Environmental analysis and preliminary design NEPA complete Procurement Final design Begin construction ti Permits Procurement NTP 1 DB preliminary design NTP 2 Begin construction DB final design Design-Build Procurement Process Request for qualifications Design-Build ild teams submit statements t t of qualifications (SOQ). WSDOT evaluates SOQs and ranks based on predetermined scoring approach. Short listed teams notified Request for Proposals (RFP) Short listed teams prepare proposals. WSDOT evaluates proposals based on predetermined scoring approach. Best value selection = technical evaluation score x $10,000,000 $ Price Proposal Fall Quarter

14 Before Advertisement of a Design-Build Contract Environmental processes mostly completed. Major permits approved. Right-of-way acquired. Preliminary design or conceptual design completed. Base data such as soil conditions and existing utilities obtained. Agreements with outside partners acquired. Project funding secured. Goals for project outcome defined. WSDOT Design-Build Projects Majority of projects are lump sum fixed price. Selected on basis of best value. Project duration is typically two to five years. Cost range is from $22 million to $1.3 billion. Cost growth historically ranged from approximately one to three percent. No claims were made on any of the 13 WSDOT projects to date. SR 16 Tacoma Narrows Bridge. Fall Quarter

15 SR 532 Recent WSDOT Design-Build Contracts SR-519 Phase Two Intermodal. SR 532 Safety Improvements and Congestion Relief. SR 520 Bridge and Landings. 520 Eastside HOV. SR 99 Tunnel Project. SR SR 520 Bridge Replacement. SR 99 Tunnel Approximately two miles long. Tunnel designed to 2,500 year earthquake standard (in the range of a 9.0 earthquake). Project cost is $1.9 billion. Design concept. Seattle Center Fall Quarter

16 South Portal Design North Portal Design Fall Quarter

17 Tunnel Boring Machine Tunnel Boring Machine Video Fall Quarter

18 Tunneling in Seattle Soils More than 150 tunnels have been constructed in Seattle since 1890, mostly in glacial soils. Examples of local projects include: Sound Transit Beacon Hill Tunnel Downtown Seattle Transit Tunnel Mt. Baker Ridge Tunnel (I-90) Denny Way Combined Sewer Overflow Burlington-Northern Railroad Tunnel. Link light rail s tunnel boring machine breaks through the east side of Beacon Hill (May 2007). Properties Above and Near the Tunnel The blue line indicates the route for the SR 99 tunnel. The areas shaded in red indicate where monitoring will take place during tunnel construction. Fall Quarter

19 Preconstruction surveys will document existing building conditions. Protecting Buildings Buildings along the tunnel alignment will be equipped with monitoring equipment to prevent and minimize possible settlement-related damage. WSDOT would be responsible for any damage caused by tunnel construction work. Crack gauge on building wall. Some buildings will need soil improvements or other mitigation in addition to monitoring. WSDOT and the contractor will identify which buildings need mitigation and the most effective method. Crews will improve soil conditions as a preventative measure where soils are soft and the water table is high. Soil Improvements Fall Quarter

20 Protecting Buildings Diagram of micropile walls. Items not not to scale to scale Construction Timeline S. Holgate to S. King Street roadway South end viaduct demolition Tunnel portals - utility relocation Tunnel portals - cut-and-cover sections, buildings Tunnel boring Interior roadway and systems On/off-ramp construction Tunnel open to drivers Central waterfront viaduct demolition Surface street improvements Fall Quarter

21 What is Construction Partnering? Working together. Building relationships. Understanding the needs of the other parties and a philosophy of teamwork. Committing to cooperation and communication. An attitude of goodwill and trust. t Sharing risks with a "win-win-win" attitude. Construction Partnering Benefits Total project costs were reduced d by 10 percent. Profitability increased by 25 percent. Overall project completion time was reduced by 20 percent. Schedule changes were reduced by 48 percent. Fall Quarter

22 Construction Partnering Workshops Partnering workshops should be attended by all project personnel with decision making authority, including: Owner representatives. Consulting engineer/architect/design firm representatives. Contractors. Major sub-contractors. Major suppliers. Major municipality representatives. Environmental officials. Safety officials. Disputes Review Board Assist in the resolution of disputes between WSDOT and the design-builder. ild Three person board of independent experts. Utilize when standard dispute resolution is unsuccessful and prior to the filing of a claim. Provide nonbinding recommendations Provide nonbinding recommendations designed to expose the disputing parties to an independent view. Fall Quarter