The Study On The Characters Of The Soft Rock Rheology And The Support Structure

With the development of traffic construction of our country, the deep weak rock tunnel and underground project increases gradually, and the construction technology of the weak rock tunnel has been greatly developed. Rheology is the intrinsic characteristic of the weak rock. For rheologic phenomena exist in various weak rock projects, the influence of rheologic phenomena has been recognized by many people. Many difficulties always exist in support of high-stress, low-strength weak rock roadway, and no better solutions are given to these problems. If the rheological characteristics of surrounding rock are taken into account, theory must be more consistent with practice, this has great practical significance.Because of the rheological characteristics of weak rock, the rheological characteristics of rock must be considered in support and design of weak rock roadway bearing long-time load, this paper tries to do this problem.This paper aims at the Lan-Xin two-ply the weak rock tunnel of Wu Shao Ling distortion speed is quick;distortion capacity is great; distortion time is long, and difficulties in support. With these concrete circumstances,choose the burgers body rheology model, detailed analysising elasto-visco-plastic finite element theory,solutions and steps of elasto-visco-plastic problems thoroughly. Finally make use of the software of FLAC to simulate the Wu Shao Ling tunnel F4 shift region construction mechanics effects, and to select the optimum support plan in F7 shift region.Mainly studied the following contents: the weak rock tunnel distortion regulation;the reasonable of weak rock tunnel support time and support in control; reasonable of in selecting the support parameter; the weak rock tunnel stability control technique.In tunnel model choicing, the stratum select the burgers body rheology that FLAC provided elasto-visco-plastic model, simulating the results accord with the actual instances.these show using elasto-visco-plastic finite difference program analyse weak rock tunnel is feasible.