采空区煤柱-顶板系统失稳的力学分析

基于温克尔假设,突破把坚硬顶板视为弹性梁的传统思想,把坚硬顶板视为弹性板,将煤柱等效为连续均匀分布的支撑弹簧,从而形成煤柱-顶板相互作用系统;同时,将煤柱视为应变软化介质,采用近似的Weibull分布描述它的损伤本构模型,依据板壳理论和非线性动力学理论对采空区煤柱-顶板系统失稳机理进行了研究,得出了系统失稳的突变机制,并给出了系统失稳的数学判据和力学条件;最后,以马脊梁矿为工程实例进行分析。结果表明,理论分析值与工程实测数据吻合较好,为进一步研究煤柱-顶板相互作用系统和制定相关规范提供了重要参考。

Mechanical Analysis of Instability of Coal Pillar and Roof System in Goaf

Based on the Winkler's hypothesis,the stiff roof was assumed as an elastic beam.It was totally different with the conventional idea that the stiff roof was assumed as an elastic plate,and the coal pillars were equal to continuously and uniformly distributed support springs.Then,the coal pillar and roof interaction system was formed.It was also assumed that the coal pillar was a strain-softening medium,and the damage constitutive model could be described by the approximate Weibull's distribution.Authors presented the instability mechanism of coal pillar and roof interaction system by using the plate mechanics and the nonlinear dynamics theory,then,the catastrophe mechanism of the system instability was gotten and the mathematical criterion and mechanical condition were given.Finally,taking Majiliang coal mine as an engineering example,the results show that a good agreement exists between the theoretical analysis vaule and engineering real test data which provides an important reference for the further research of the coal pillar and roof interaction system and constitution of relevant codes.