Project Description
Context of the project
This high-speed train line connects Hong Kong with Guangzhou in 48 minutes.
Description of the project
Bachy Soletanche Group Limited was part of the integrated consortium which was awarded Contract 811 A (Express Rail Link). The scope of works comprises the construction of a 300 metre long cut-and-cover tunnel in a dense urban environment.
Our solution
During the first phase, advanced utility and traffic diversion works were completed. In particular, a viaduct was completely dismantled and rebuilt at a different location. In the second phase, the geotechnical works which comprised an excavation of a 240,000 cu. metre “box” of 30 deep metre, was carried out. The third and last phase consisted in building the permanent reinforced concrete underground structure inside the diaphragm wall and a building to accommodate the mechanical and electrical rooms. The main technical difficulty of the project lies with the crossing of the existing metro line. This imposes a very specific sequence of works and limits the allowable settlement and displacements.
The existing line being founded on barrettes socketed into the rock, BSGL has proposed to re-use them to support the newly built structure. The final task, the load transfer from the old to the new structure, was a very delicate operation.
Key figures of the project