摘要
为了研究动载作用下底板冲击矿压的演化规律,采用理论分析和数值模拟的手段研究了动应力波作用下巷道底板煤体的应力和位移等参数的响应特征,揭示了动载扰动诱发底板冲击的原因和显现过程。研究结果表明:动应力和巷道底板的高水平应力叠加使底板煤体达到或超过强度极限发生屈曲失稳和变形,并且应力波入射到底板表面反射形成拉应力导致底板发生层裂破坏,在这过程中破坏范围逐渐扩大,导致底板冲击。动载作用过程中底板煤体的水平应力、垂直应力、应力差先上升后瞬间大幅度降低,同时底板煤体拉伸破坏的层裂破坏范围和垂直位移瞬间增加,在此过程中,底板水平应力集中现象逐渐消失。
To research the evolution laws of floor burst under dynamic loads,theory analysis and nu-merical simulation methods were used in this paper,to study the response characteristics of stress,dis-placement,et al,of roadway bottom coal under dynamic disturbance,and to reveal the causing reason and burst process induced by dynamic stress.The results show that the buckling failure and deformation will happen in the bottom coal seam,when the superposition of dynamic stress and high horizontal stress in floor reaches or surpasses the strength limit.In addition,the tensile stress,which is formed by the reflection of incident stress wave at the floor surface,causes spallation damage in the floor,and with the gradual enlargement of the damage range,the floor burst will be induced.Under the dynamic load-ing,the horizontal stress,vertical stress and stress difference firstly increase in a small extent,and then decrease substantially.At the same time,the scope of tensile failure zone and the vertical displacement increase subsequently.During the process,the concentration of horizontal stress in floor disappears gradually.
出处
《采矿与安全工程学报》
EI
北大核心
2012年第3期334-338,共5页
Journal of Mining & Safety Engineering
基金
国家重点基础研究发展计划(973)项目(2010CB226805)
国家自然科学基金项目(51104055
51074155)
河南省教育厅自然科学研究计划项目(2010A440003)
河南理工大学青年基金重点项目(Q2011-42A)
关键词
动载扰动
底板冲击
演化规律
数值模拟
dynamic disturbance
floor burst
evolution law
numerical simulation