I-35W Bridge. Khani Sahebjam, PE. From Tragedy to Triumph. Vice President HDR Engineering, Inc. Former Deputy Commissioner/Chief Engineer MnDOT

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1 I-35W Bridge From Tragedy to Triumph Khani Sahebjam, PE Vice President HDR Engineering, Inc. Former Deputy Commissioner/Chief Engineer MnDOT

2 History Bridge background Bridge completed feet long 3 span continuous truss Main span 456 feet ADT 141,000 Sufficiency rating 50.0 Annually inspected I-35W Bridge - Looking North July, 1967 In depth fracture critical 500 hours annual average by MnDOT maintenance Scheduled replacement

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5 August 1, 2007 The Collapse Collapse occurs at 6:05 pm Wednesday, August 1, 2007 Over 100 vehicles on the bridge at the time 13 fatalities, 140 injuries

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12 Emergency Response 6:05 p.m. Numerous calls to 911 Motorists on bridge, construction workers, citizens in area assist injured Emergency personnel from Twin Cities and Western Wisconsin respond MnDOT s Regional Transportation Management Center (RTMC) 6:10 p.m. District Emergency Operations Center activated Immediate traffic control for ramp and freeway closures provided by FIRST units, maintenance units, and contractors in the vicinity

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14 Response the First 12 Hours Unified command center set up on collapse site. Minneapolis Fire Department in charge of rescue operation Hennepin County Sheriff in charge of recovery August 1, 2007

15 First 12 Hours continued 7:00 p.m. More than 150 employees activated, most just returned without a call 10:00 p.m. Governor and Mayor provide an update to public. Number of victims unknown. Rescue operations ended, recovery begins 11:00 p.m. Detour maps for a.m. rush posted on MnDOT web site Overnight Expanded signing and barricades of closed I-35W Converted TH 280 to a freeway

16 I-35W Detour Map

17 August 2, 2008 MnDOT Engineers assess stability of wreckage for recovery personnel MnDOT retains Wiss Janney Elstner and TranSystems / Lichtenstein for forensic investigation Command Site Federal Agencies arrive at command site FEMA, FBI, Coast Guard, OSHA, OIG, FTA, NTSB, Rick Capka, and National FHWA staff NTSB leads investigation team MnDOT engineering team begins to organize for rapid replacement

18 Media Coverage August 2, 2008 Governor Conducts interviews throughout morning 2 p.m. news conference Governor announces NTSB Chairman Mark Rosenker Emergency Statewide Bridge Inspections beginning with underdeck trusses Forensic Investigation Team Wiss Janney Elstner Transystems MnDOT provides bridge background and responds to questions National and International News Organizations present National Transportation Safety Board updates

19 Responding to Media Requests Daily 2 pm news conference Became only means to respond to volume of requests Format - statement, update on specific issue, take questions Length was 30 to 45 minutes When it ended, held questions till next day MnDOT goal was transparency Document requests were voluminous Website posting of plans, inspection reports, bridge studies Dedicated I-35W website included all documents August 3 Press Conference Media on Top of Nearby Buildings

20 Responding to Media Requests continued MnDOT priority was local media requests Within days, some media began own investigations and speculation Correcting factual errors consumed time Spectators and media on adjacent 10th Avenue Bridge

21 Recovery of Victims Aug 6 Careful bridge demolition began to aid recovery and NTSB investigation Navy divers from Norfolk, VA assist in recovery NTSB investigation team supervises removal All steel members marked and indexed Members removed by torch underwater cuts could take 1-4 hours Extensive coordination required with divers, sheriff, investigator,s and contractor Balanced desire to recover victims vs. need to preserve evidence Navy Dive Team Diver Perspective

22 Recovery of Victims continued Aug. 20 Navy Divers recover 13th victim, site turned over to MnDOT Sept. 6 - Navigation channel opened to commercial traffic Sept. 27 Final steel removed from river Removing Wreckage from Navigation Channel

23 Executive Branch Response Aug 3 - First Lady Laura Bush visits the site and victim s families Aug 4 - President Bush pledges to cut red tape that could delay recovery Aug 21 - President declares emergency under Robert T. Stafford Act authorizing funds for safety and recovery efforts

24 Traffic Restoration Work to convert Hwy 280 to a freeway including closing at-grade signalized intersections to cross traffic, upgrading ramp termini signal systems and lengthening frontage road Add lane each direction on I-94 from Hwy 280 to I-35W by overlaying and restriping shoulders Many temporary projects on other Metro alternate routes

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26 NTSB Investigation

27 Construction Materials Staging Piles of aggregate Construction equipment and vehicles U10 west node

28 Dead Load of Original 1967 Bridge Stress Orange and red shading: exceeds yield stress Yield stress Allowable 0 Tension diagonal Compression diagonal

29 After 1977 and 1998 Modifications Orange and red shading: exceeds yield stress Stress Yield stress Allowable 0 Tension diagonal Compression diagonal

30 Loads at Time of Accident Orange and red shading: exceeds yield stress Stress Yield stress Allowable 0 Tension diagonal Compression diagonal

31 Accident Loads on 1-Inch-Thick Gusset Plates Stress Yield stress Allowable 0 Tension diagonal Compression diagonal

32 Bridge Rebuild Legislative/Congressional Hearings Aug 15 Hearings with Minnesota House and Senate Transportation Committee Sept 5 MnDOT staff testified before the U.S. House of Representatives Committee on Transportation and Infrastructure

33 Timeline August 1 Bridge Collapses August 4 Issue Request for Qualifications August 8 Short Listed Teams August 23 Request For Proposals Released September 14 Technical Proposals Received & Technical Evaluation Begins September 18 Financial Proposals Received September 19 Project Letting September 20 City of Minneapolis Grants Municipal Consent October 8 - Project Award to Flatiron/Manson November 15 Construction begins

34 Evaluation Criteria Quality (50 percent) Experience and authority of key individuals Extent of quality control/quality assurance Safety Measures to evaluate performance in construction Aesthetics/Visual Quality (20 percent) Visual enhancements to the structure Involvement of the public after letting Enhancements (15 percent) Roadway enhancements Structural enhancements Public Outreach/Involvement (15 percent) Impacts to the public Approach to communications

35 Best Value Selection Process Based on cost plus time divided by technical score Resulted in Flatiron/Manson being awarded the best value contract technical score $233.8 million cost 437 days to complete

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39 Pier Shape

40 Open Railing Drivers perspective heading southbound towards city center

41 Retaining Walls

42 Safety Lighting

43 Mass Concrete

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45 Cold Weather Protection

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53 Eco-friendly Concrete Inspired by ancient symbol for water A new self-cleaning and pollution eating concrete One on each end of bridge

54 Why Project was Successful Common goal by all Funding in place within days Well prepared Sound partnerships Streamlined processes Servant leadership Situational leadership

55 Outcomes Process changes Inspections (Gusset plates) Design procedures Peer review of design for major bridges Maintenance follow up Placement of construction material on bridges NTSB reports gusset plate design flaw main cause of collapse State established $38 million to compensate survivors and families of those who died

56 Current Status Building public trust and confidence in transportation system and MnDOT Litigation continues State paid Plaintiffs Bridge Contractor settled with Plaintiffs Consultant A settled with State Consultant A settled with Plaintiffs Consultant B settled recently with MnDOT

57 Washington State I-5 Skagit River Bridge Bridge Collapse May 23, 2013 Temporary Bridge Extension

58 Washington State I-5 Skagit River Bridge No fatalities Fast recovery Truck hit Funding debate

59 Questions? Thank you.