摘要
根据三维裂纹前沿局部坐标系中主法平面内的周向应力计算公式,可以确定主法平面内的最大周向应力σθ,并由最大周向拉应力裂纹破裂准则确定裂隙岩体的破裂载荷和裂纹的破裂方向以及破裂步长。在三维无网格方法的节点的影响域中,选择合适的节点密度,以确保计算精度,并对单向轴压条件下内置三维裂纹扩展进行了数值模拟研究。根据数值计算结果,分析了破裂载荷、裂纹扩展角和扩展步长,揭示了内置三维裂纹的破裂过程,结合插值法清楚地展示了三维裂纹的破裂曲面形态。研究结果表明,针对三维裂纹破裂过程和破裂曲面形态无网格方法数值计算结果与FLAC-3D计算结果和试验结果吻合较好。
The maximum hoop stress is determined by the hoop stress calculation formula in the principal normal plane at 3D crack front. The maximal circumferential tensile stress criterion is adopted to determine the crack propagation load, orientations and steps. In the impact domain of node in 3D mesh-less method, the appropriate node density is selected to ensure the calculation accuracy, and built-in 3D crack propagation under uniaxial compression is numerical simulated. According to the numerical results, the cracking loads and crack propagation angles and expansion steps are analyzed, the rupture process of built-in 3D crack is revealed and the rupture shape of build-in 3D crack is clearly shown combined with interpolation method. The study indicates that the numerical results of meshless method agree well with that of experiment and that of FLAC-3D for three dimensional crack fracture process and fracture surface morphology.
出处
《应用力学学报》
CAS
CSCD
北大核心
2016年第3期483-489,550,共7页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金(51279095
51379114
51139004)
