Surrounding Rock Deformation Control for Deep-Buried Soft-Rock Tunnels
(1 State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071; 2 University of Chinese Academy of Sciences, Beijing 100049; 3 Power China Huadong Engineering Corporation Limited, Hangzhou 310041)
Abstract：
Deformation control is a main measure for controlling the stability of soft-rock tunnels. Control indexes and methods for deformation and deformation rate are proposed in relevant specifications and literatures, but most of them focus only on convergence identification and are summarized based on construction experience in shallow tunnels, which makes them less appropriate as a basis of adjustment and control of stability during construction and not very suitable for deep- buried tunnels with high rock deformation pressure. Based on an analysis of the rock mass deformation characteristics of the squeezing section of a deep- buried chlorite schist tunnel, a multi-index rock stability control method that considers the indices and modes of deformation and deformation rate is proposed,and timely adjustment measures for rock mass stability are available in light of the time-space effect during construction, eliminating squeezing deformation of the surrounding rock in the deep-buried soft rock tunnel.
2018, Vol. 55 