Abstract:

Due to the rapid development of economy, the living qualities are continuously upgraded. The building of electricity power is aimed to meet the needs of urbanization and modernization. Installing extra high voltage cables into underground tunnels is the current trends. In this paper, the turnkey project for the extra high voltage cable shieldbored tunnel conducted by Taiwan Power Company is given. This project is located at the site with such geological characteristics as high water table, sandy soil and gravel formations. The experience in the safe launching of the shield machine from the shaft and in the construction of the largediameter tunnel at sharp turn has been described in this paper. In addition, it is the first time in Taiwan that flexible expansion joints are used to connect the cable tunnel and the divert shaft. The flexible expansion joint can effectively reduce the stress concentration in joints and overcome the deformations occurring between the different types of structures.

Key words: cable tunnel, shield tunneling method, flexible expansion joint, divert shaft