摘要
为了研究隧道施工过程中石膏质围岩软化特性,以三叠系下统嘉陵江组地层中的石膏岩为研究对象,进行了多因素正交软化试验研究,分析了浸泡时间、溶液温度、24SO-浓度对石膏岩软化后力学参数的影响规律。研究结果表明:石膏岩的软化系数和弹性模量随着浸泡时间的增加而减小,减小速率也随之降低;软化系数和弹性模量随溶液温度的升高而呈线性减小;在影响石膏岩软化后力学参数3个因素中浸泡时间的影响最大,权值高达80%,温度次之,权重为16%左右,而24SO-浓度对石膏岩的软化影响非常微弱;建立了浸泡时间与溶液温度两个因素耦合作用下石膏岩软化后单轴抗压强度与弹性模量变化情况预测公式。在试验数据及结论的基础上从围岩坚硬程度划分、防排水措施及支护措施等方面提出了石膏围岩隧道的施工措施及建议。
This paper aims to study the softening characteristics of gypsum surrounding rock in the construction process of the tunnel. The multi-factor orthogonal softening experiments were carried out on gypsum rock from Lower Triassic Jialing River Formation. Then we analysed the effects of immersion time, solution temperature and SO_4^（2-）concentration on mechanical parameters of gypsum rock after softening, respectively. The results showed that both the softening coefficient and the elastic modulus decreased with the increase of immersion time, furthermore their decreasing rates showed the same patterns. It was also found that they linearly decreased with increasing the solution temperature. Among these three influencing factors, the immersion time played the most critical role in softening experiments, and its weight was up to 80%. However, the effect of temperature ranked second with its weight of about 16%, and the effect of SO_4^（2-）concentration was very slight. The prediction formulas were established for the elastic modulus and the uniaxial compressive strength of gypsum rock under the coupling action of the immersion time and the solution temperature. By analysing the experimental results, the construction methods and suggestions for gypsum rock tunnels were put forward from the aspects of the division of surrounding rock hardness, prevention and drainage measures and the supporting measures.
作者
任松
李振元
邓高岭
刘伟
蒲文明
REN Song1, LI Zhen-yuan1, DENG Gao-ling1,2, LIU Wei1,3, PU Wen-ming4(1. State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; 2. Changsha Institute of Mining Research Co., Ltd., Changsha, Hunan 410006, China; 3. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; 4. Chongqing Liangzhong Highway Overall Contracting Units, Power China Road Bridge Group Co., Ltd., Chongqing 405200, Chin)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2018年第3期789-796,共8页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.51774057)
中央高校基本科研业务费(No.106112016CDJZR245518)
重庆市基础与前沿研究计划项目(No.cstc2015jcyj A90011)~~
关键词
石膏岩
软化特性
正交试验
影响权值
gypsum rock
softening characteristics
orthogonal softening experiment
effect weight
