岩土力学2025，Vol.46Issue(2)：613-624,12.DOI:10.16285/j.rsm.2024.0041
考虑蠕变剪裂的拉格朗日元与离散元耦合方法及应用
Lagrangian-discrete element method considering creep shear cracking and its application
摘要
Abstract
As mining depth increases,the large deformation of soft rock,such as roof fall,floor heave and two-side movement of the tunnel,poses a severe challenge to safe mining.Currently,continuous-discontinuous methods,combining advantages of both continuous and discontinuous methods,are rapidly developing.However,creep has not yet been introduced into these methods.Based on the experimental phenomenon that rock creep failure strain occurs in the post-peak region of the triaxial compression stress-strain curve,the viscoelasticity of the element is considered.A creep shear cracking model is developed to account for the viscoplasticity of the interface,and a criterion of creep shear cracking is introduced into the combined Lagrangian-discrete element method(a kind of continuous-discontinuous method)to simulate the creep shear cracking.The calculated creep curve under uniaxial compression aligns closely with experimental results.Once creep shear cracking begins,the specimen enters the accelerated creep stage.The proposed method has the potential to simulate accelerated creep.Results of the soft rock tunnel indicate that discrete blocks move into the tunnel due to the pushing of deep rock,sharply reducing tunnel size.Macroscopically,the tunnel exhibits a large deformation.The tunnel's vertical shrinkage rate can reach 58.8%.The mechanisms of large deformation in the soft rock tunnel,attributed to the viscoelasticity of the element and the viscoplasticity of the interface(fictitious crack surface),result from a combination of small viscoelastic deformation of the medium,large block displacement,and viscoplastic deformation of the interface.It is unnecessary to describe the tunnel's macroscopic large deformation using complex large deformation theories.关键词
软岩/蠕变/大变形/巷道围岩/连续-非连续方法/黏弹性/剪裂Key words
soft rock/creep/large deformation/surrounding rock of roadway/continuous-discontinuous method/viscoelasticity/shear cracking分类
建筑与水利引用本文复制引用
王学滨,陈双印,郑一方,廖裴彬..考虑蠕变剪裂的拉格朗日元与离散元耦合方法及应用[J].岩土力学,2025,46(2):613-624,12.基金项目
国家自然科学基金(No.52474101). This work was supported by the National Natural Science Foundation of China(52474101). （No.52474101）
