摘要
为评价应变软化模型中内聚力对模拟结果的影响,利用FLAC3D软件建立标准尺寸的圆柱体模型,采用单向加载方式开展数值模拟研究。结果表明:采用摩尔库伦模型时,内聚力大小与峰值强度呈线性相关。在应变软化模型中,仅改变应变软化参数,峰前特性与摩尔库伦模型表现一致;其他条件相同时,峰后塑性应变的标志点越小,或峰后应变软化参数与峰前参数差值越大,峰后的应变软化效果越明显。软化标志点较大或内聚力软化程度较小时,这种现象都不明显。在FLAC3D中一般将软岩的内聚力软化,即可达到相应的软化效果,而无需对内摩擦角、抗拉强度软化。同时,在常规数值模拟中采用峰后能量反映冲击倾向性很可能是不够准确的。
In order to evaluate the effect of cohesion on simulation results of strain-softening model,standard size numerical cylindrical samples were established in FLAC3D software,and the comparative numerical simulation study were carried out by uniaxial loading.The results showed that when using the Mohr-Coulomb model,the cohesion was linearly related to the peak strength.While in the strain-softening model,when only the strain-softening parameters were changed,the performance of the samples before the peak were consistent with the behavior of the Mohr-Coulomb model.When the other conditions were the same,the smaller the marker point of the plastic strain after the peak became,or the greater the difference between the post-peak strain-softening parameter and the pre-peak parameter was,the more obvious the post-peak strain softening effect would be.However,this phenomenon was not obvious when the softening marker point was large or the softening degree of cohesion was small.For soft rocks,cohesion was generally softened in FLAC3D to achieve the corresponding softening effect without the need to soften the friction angle and tensile strength.Meanwhile,it was most likely not accurate enough to reflect bursting liability by post-peak energy in conventional numerical simulations.
作者
杜学领
DU Xueling(Institute of Mining Engineering,Guizhou Institute of Technology,Guiyang 550003,Guizhou,China)
出处
《河南理工大学学报（自然科学版）》
CAS
北大核心
2021年第4期186-193,共8页
Journal of Henan Polytechnic University（Natural Science）
基金
国家自然科学基金资助项目(51764010)
国家留学基金资助项目(201908520017)
国家安监总局2018年安全生产重大事故防治关键技术科技项目(guizhou-0005-2018AQ)
贵州理工学院高层次人才科研启动经费(0203001018029)。
