【摘要】 基于大坪山隧道工程地质条件及可能穿越高地应力而带来的深部工程地质问题,结合钻孔有限测点的地应力测量结果,采用三维有限元分析方法对大坪山隧道的初始地应力场进行了拓展分析。通过建立三维地质模型,计算在自重应力、水平X、Y方向挤压和XY面剪切构造等4种工况下的构造应力场。用最小二乘法求解对应的回归系数及实测点的回归计算值,剔除不合理的测点,将计算值与实测值进行对比分析,采用Sufer软件绘制隧道洞轴线主应力等值线图,得出整个工程区特别是重要工程部位的回归初始地应力场。计算结果表明:测点回归值与实测值大部分吻合较好,反演回归得到的地应力场是合理的,符合实际的初始地应力场分布规律。更多还原

【Abstract】 Based on the engineering geological condition and deep engineering geological problems which might to be brought by high geostress of Daping mountain tunnel and the engineering geological problems brought by high geostress,combined with the data of in-situ stress obtained at limited drilling measuring points,the expansion analysis of initial geostress field of the tunnel area was conducted by 3D FEA method.A 3D FE computational model was established to compute the tectonic stress fields in four cases,including gravity stress,horizontal extrusion in X and Y directions and shear structure in XY plane.The corresponding regression coefficients and the calculation values of the measuring points were solved by using the least square method,and then the calculation values of the unreasonable measuring points was eliminated.Through comparison between the calculated and measured geostresses of measuring points,the principal stress isoline of tunnel axis was plotted by using Sufer software to obtain the regressed initial stress field of the whole area especially the important engineering parts.The result shows that the calculation values agree well with the measured values mostly,which suggests that the geostress field obtained by regression is reasonable and conforms to real distribution regularity of the initial geostress field.更多还原