摘要
采用二维格构模型分析了岩石中锚杆拔出试验。格构模型将材料在细观尺度上离散为由梁单元组成的格构系统。单元采用简单的本构关系和破坏准则,假定单元的抗拉强度服从正态分布,以引入岩石的非均质性。在外载作用下对整体网格进行线弹性分析,计算出格构中各单元的局部应力,超过断裂阈值的单元将破坏,材料的开裂过程通过单元的依次破坏来模拟。研究中考察了材料非均质程度、约束条件对开裂机理的影响。数值结果表明,非均匀性导致了开裂形态的非对称性,而增加水平约束后,试件的荷载-位移反应由脆性变为柔性。
The pullout behavior of steel anchor embedded in rock is analyzed using lattice model.In the model the continuum is regarded as a connected lattice with elasticbristle beam elements.Fracture is simulated by performing a linear elastic analysis of the lattice under loading and removing an element from the lattice that exceeds a certain breaking threshold.The breaking threshold is chosen randomly from normal distribution to incorporate material heterogeneities.The influence of heterogeneity and boundary conditions on final cracking patterns and loaddisplacement curves are investigated.It is concluded that the crack patterns and associated loaddisplacement response are significantly governed by the heterogeneity,load patterns and boundary conditions.
出处
《水利学报》
EI
CSCD
北大核心
2002年第12期68-73,共6页
Journal of Hydraulic Engineering
基金
国家自然科学基金资助项目(59879005)
