Throughout the rest of the system, workers will replace segments of rail and upgrade power substations, rebuild interlocking components on the tracks and replace high-voltage transformers, upgrade fire and tunnel lighting systems, and replace stretches of its electric cables, among other projects. They’ll also install an upgraded pumping system that will allow larger quantities of water to be removed more quickly from the tube, should water make its way in. Crews will line key sections of the 3.6-mile tube with curved steel plates, using grout to adhere the plates to the tube’s concrete walls, and a polymer product under the tracks to prevent against possible leaks. The remaining seismic retrofit work in the Transbay Tube is the last project in a host of earthquake upgrades voters approved in 2004 as part of $980 million in Measure AA bonds for the $1.2 billion program. But, agency officials want to make sure it’s still safe should the center of a catastrophic earthquake strike closer to the core of the system.
The tube withstood the Loma Prieta earthquake of 1989, running 24-hour service just 12 hours after the quake struck. San Francisco, CA November 1967 – Binocular-shaped sections of the transbay tube were constructed in a shipyard then sunk in the Bay. Adding extra hours for workers will enable the agency to get 43 percent to 62 percent more work done and shave months off construction, officials said. It takes crews some time to set up equipment at night and then break it down before the start of the morning commute, creating a limited window of “wrench time” to actually get to work. The service changes will allow the agency to complete the more than $300 million retrofit of the Transbay Tube, shoring the essential transit artery in the event of a major, once-in-1,000-years earthquake, while also performing needed repairs and upgrades throughout the system. As the massive seismic retrofit of the Transbay Tube gets underway, BART on Monday will begin subbing buses for trains in its first hour of service and single-tracking trains after 9 p.m.
0 kommentar(er)
