摘要
利用弥散裂缝理论,提出了压实黏土拉伸状态下的脆性断裂模型。当压实黏土达到其极限抗拉强度后,通过建立单元的各向异性刚度矩阵,将土体裂缝弥散于实体单元,构造了平面应变条件下考虑压实黏土脆性开裂的有限元计算模式。通过对某压实黏土单轴拉伸试验成果的模拟计算,验证了构建的脆性断裂模型和有限元算法对土体拉伸破坏特性和裂缝发展过程的适用性。本文还进行了模拟软弱面水压“楔劈效应”的简单数值试验,表明压实黏土脆性开裂模型和算法可较好地模拟裂缝扩展行为。
Based on the smeared cracking theory, a brittle fracture model for tensile state of compacted cohesive soil is proposed. When tensile strength is reached, cracks are smeared into solid elements by constructing anisotropic stiffness matrix. The finite element method for brittle fracture in compacted cohesive soil is built under the plane strain condition. By simulating of the process of uniaxial tensile tests on a certain cohesive soil, the applicability of the brittle fracture model and the corresponding calculation method for tensile failure and crack development is verified. More over, simple numerical tests to simulate the ＂wedging action＂ of water pressure in weak link are carried out; and the results show that the model and the method can simulate well the behavior of crack development.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2006年第9期1527-1531,1540,共6页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.50579029)。
关键词
弥散裂缝
脆性断裂
单轴拉伸试验
压实黏土
smeared cracking
brittle fracture
uniaxial tensile test
compacted cohesive soil
