Design and construction of first bored tunnel under Ho Chi Minh City Metro Line 1 in Vietnam

This paper presents details on the design and construction of the first bored tunnels in Vietnam. These tunnels are part of the Ho Chi Minh City Metro Line 1 Project and consist of two bored tunnels each having a single track. The tunnels were constructed using Earth Pressure Balance Tunnel Boring Machine and were successfully completed in October 2018. The Two-Ring Beam Spring Structural Model was used to design the tunnel lining segments that had to be fabricated off-site. During construction the member forces developing in the installed segment lining were monitored and have been used for back analysis to verify the design model. Additionally, several instruments were deployed to monitor ground surface settlement and displacement, during construction. The data from these instruments was used to reconfigure the TBM driving and form part of the discussions in this paper.