摘要
准确选择岩石本构关系直接影响数值计算精度.利用常规三轴压缩作用下砂岩应力-应变全曲线规律,定义损伤阈值点,将整体变形过程简化分解成三个区段,在每一区段上建立本构关系理论模型.分析砂岩应力、应变全过程曲线上各类阈值点强度与围压之间相互关系,建立各类阈值点强度与围压关系式,得到不同围压条件下砂岩本构关系模型.通过室内常规三轴物理试验证明理论本构关系模型可以较好逼近试验结果.利用APDL语言将该模型嵌入ANSYS程序非线性分段弹性计算模块中,分析顶板来压、冲击载荷作用过程围岩应力演化规律.研究发现,来压过程中巷道顶角压力显著增大,高于地应力平均水平3倍以上;顶板压力在瞬时冲击荷载作用时域内基本不变,冲击荷载作用下顶板应力分布存在明显分区,应力最大值高于输入冲击荷载1.48倍.
Numerical calculation accuracy apparently depends on rock constitution option.Total rock deformation process was divided into three stages,based on threshold defined in regular tri-axial compression experiment.Constitution relationships were founded based on every stage.Relationship between threshold point intensity and confining pressure was analyzed.Relational expression about confining pressure and damage threshold point intensity were established.Model was introduced into ANSYS using APDL language to study surrounding rock stress distribution regulation with effect of roof weight and transient shock load.The results of study show that stress in corner of roadway increases approximately 3 times of the in situ stress,in circumstance of roof weight process,and roof stress remains unchanged nearly within domain of transient shock load,in which the obvious partition exists.Maximum stress is 1.48 times greater than shock load input.
出处
《辽宁工程技术大学学报（自然科学版）》
CAS
北大核心
2018年第3期534-540,共7页
Journal of Liaoning Technical University (Natural Science)
基金
国家自然科学基金(51504159)
太原理工大学大学校青年(团队)基金(2014TD008)
关键词
砂岩损伤
常规三轴试验
本构关系
围岩应力
数值计算
sandstone damage
regular tri-axial experiment
constitutional relation
surrounding rock distribution
numerical calculation
