That is equivalent to a magnitude-8 temblor on the nearby San Andreas fault. Essential Facilityĭesignated an essential facility by the city, the hub was engineered to be available for immediate occupancy after a 975-year earthquake, said Bruce Gibbons, a TT managing principal, in "Transportation Hub Will Be a Safe Haven", posted on ENR.com on 6/29/15. Both the bus deck and green roof extend beyond the ground-level footprint by about 23 ft. The building, which stretches 4.5 blocks, is 1,425 ft x 171 ft and 75 ft tall. Above that, a bus deck connects to nearby streets and the San Francisco-Oakland Bay Bridge via ramps and bridges. Two levels of public space, retail and offices occupy both ends of the building, with a double-height grand hall in the middle. General contractors Skanska USA Civil West, Balfour Beatty Infrastructure and Shimmick Construction held major subcontracts.īelow grade, the concourse and train platforms will serve future rail connections. performed construction management oversight and quality assurance. Webcor issued the following statement: “We are pleased to be part of the team that TJPA has asked to investigate what led to the crack in the steel beam. We are just beginning work and do not have any information about the cause or causes of the issue at this time.”
TT is also involved in the investigation, but is referring all inquiries to TJPA, as are other members of the design and construction team. What is the load hanging from the girders? Is this a welding stress problem? What are the spans? How did this happen? What is the likelihood of other fissures developing over time? Questions remain unanswered, beyond the shoring plan and the fix.
The photos also suggest they are welded tapered plate girders. Sources are not providing any details about the cracked members, except to say the average depth is 6.5 ft, but the girder in the photos released by the TJPA is about 8 ft deep.
0 kommentar(er)
