By rosebell
Providing an insight into construction activity under way at the West Portal site, the launch point for the TBM that will extend the BART service through downtown San José into Santa Clara, the Santa Clara Valley Transportation Authority (VTA) gave news media a behind-the-scenes tour of the BART Silicon Valley Phase II Project (BSVII) on 8 December.
While the West Portal was described as the symbolic and literal gateway to Silicon Valley’s future transit network by project leaders, currently crews are building the massive Caterpillar Shaft where the TBM is due to be lowered to commence its drive.
In order to continuing forming the shaft and tunnel walls, over than 310m3 of concrete, almost 100 truckloads were poured in this week alone, whereas steel reinforcement cages are being assembled on site, creating a structural framework to stabilise the deep excavation.
Considering that crews continue to dig deeper into the future tunnel box, large steel bracing is being installed to stabilise the walls and in the U-wall area, approximately 14% of excavation has been completed.
During the tour, VTA emphasised its commitment to safety and innovation, including advanced sensor technology being used to monitor ground and structural movement in real time. Additionally, crews are preparing electrical infrastructure – including transformers and power panels – that will power the TBM and other essential systems.
Transporting the BART train service from the existing Berryessa/North San José through downtown San José to the city of Santa Clara,VTA’s BSVII Project is a 10km, four-station extension. The project includes an around 8km tunnel, which includes three underground stations (28th Street/Little Portugal, Downtown San José, and Diridon), one ground-level station (Santa Clara), and maintenance facilities.
