基于强度折减法的巷道整体安全系数探讨分析

将有限元强度折减法应用到高地应力下巷道的稳定性评价。选用矩形、直墙半圆拱形、直墙半圆拱加反拱形、马蹄形及圆形等5种巷道常用断面开展计算研究。就上述5种典型断面,利用有限元分析软件ANSYS12.0分析了岩土体折减系数对巷道代表点的位移及围岩塑性区的发展的影响,再现了巷道断面岩土体变形发展过程。通过观察围岩塑性区的发展和巷道控制点的位移突变,求得各断面形状的安全系数并找出其潜在破坏面。根据安全系数的大小和破坏面的位置,能够评定巷道断面设计的合理性,并对施工工艺和支护参数提出改进建议。

Exploration of General Safety Factor of Roadway Based on Strength Reduction FEM

Strength reduction finite element method was used for stability evaluation of roadway in highly stressed rock.Five roadway sections,a rectangle,a straight wall with arched top,a straight wall with arched top and inverted arch,a horseshoe shaped and a circle were studied.With regard to the above-mentioned roadwag sections,using the software ANSYS12.0,the eftects of surrounding rock strength reduction coefficient on displacement of representative points and development of the plastic zone of surrounding rock were analyzed,and deformation process of surrounding rock was simulated.The latent rupture area was located and safety factors for roadwag section forms were obtained.The rationality of the designed parameters of support and excavations can be judged on the basis of the safety factor and the location of the latent rupture area.