考虑应变软化的高速公路软岩隧道围岩变形分析

软岩隧道具有变形大流变时间长等特点，采用何种模型模拟软岩的应力应变关系在数值计算中至关重要。通过数值模拟和三轴试验对比，确定以驼峰曲线函数表达式描述软岩的应变软化材料特性关系，结合 FLAC 软件采用应变软化模型对三种开挖方式进行了模拟计算分析，确定最优开挖方式。然后针对软岩围岩变形进行了理想弹塑性模型和应变软化模型的分析对比。将软岩应变软化本构模型得出的围岩变形与实测值进行对比分析，发现其二者值能够较好吻合，因此采用应变软化模型计算软岩隧道变形是可取的。

The Strain Softening Simulation and Application in Expressway Tunnel under Soft Rock Geological Condation

The soft rock tunnel has many characteristics such as large deformation and long rheological time .Choosing the right model to simulate stress-strain relationship of soft rock is very important .In this research ,by comparing the nu-merical simulation and triaxial test ,we determined to use the hump curve function expression to describe the strain soft-ening material properties of soft rock .FLAC software was adopted to develop the strain softening model three excavation method for the numerical simulation analysis ,it can be found that different excavation ways have great influence on the stability of surrounding rock ,determination optimal excavation method .Comparing the numerical simulation results and the measured values the results of strain softening model agree well with field observation data .Thus using the strain soft-ening model to simulate the stress field and displacement field of soft rock tunnel is feasible .This paper could provide valuable information to similar engineering design .