摘要
通过对比室内三轴试验和颗粒流程序双轴数值试验结果,确定了颗粒流模拟砂土的细观参数;通过对室内挡板下落试验的颗粒流数值模拟,验证了颗粒流模拟土拱效应的可行性。在此基础上对盾构隧道垂直土压力的松动效应进行了颗粒流模拟,分析了不同盾尾空隙、不同埋深、不同直径和不同围岩时作用在管片上的土压力、土体位移和土体颗粒接触力的变化情况。结果表明,土拱效应主要发生在隧道上部1～2倍隧道直径的范围内,隧道顶部土体通过土拱效应可大幅度减少作用在隧道上的土压力。
Compared the results of laboratory triaxial tests with those of biaxial tests in the particle flow code, the microscopic parameters were determined, and sand characteristics in particle flow code were simulated. Simulation of soil arching by particle flow code was proven feasible through comparison of the results of trapdoor simulated by particle flow code with those of trapdoor tests. Based on the above study, the model of particle flow code was established for simulation on relaxation effect of vertical earth pressure in shield tunneling, and then was used to analyze the earth pressure on the lining, earth displacement and contact force between soil particles considering the factors of ground loss, buried depth and diameter of tunnels and soil properties. It was indicated that the soil arching mainly took place within the range of soil of 1-2 times the tunnel diameter above the tunnel, and that the earth pressure acting on the tunnel lining decreased greatly because of the soil arching.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2008年第5期750-754,共5页
Chinese Journal of Geotechnical Engineering
关键词
盾构隧道
垂直土压力
松动效应
颗粒流模拟
shield tunnel
vertical earth pressure
relaxation effect
particle flow simulation
