Evaluating Interaction Between Structural Supports and Sedimentary Rock for a Tunnel with Penstock at a Hydropower Plant in Laos

Interaction between underground structural supports and rock is a complex matter. In this paper, the authors evaluate behavior of interaction between structural supports and sedimentary rock for a tunnel at a hydropower plant in Laos. The tunnel is located at the depth of 250 m in medium to heavily weathered sedimentary rock with 605 m length. The tunnel is supported by reinforced concrete lining. It is designed to contain a steel penstock which is supported by support blocks and anchor blocks. The monitoring instruments are installed for reinforcement in concrete lining. Monitoring data are important values to evaluate stability of tunnels during operation phase as well as to evaluate behavior of interaction structural supports and sedimentary rock using in future design of tunnel lining.