Coal Mining & Design Branch, China Coal Research Institute Coal Mining & Designing Department, Tiandi Science
& Technology Co., Ltd.

为解决坚硬顶板工作面刀柱式采空区对上部煤层开采影响的问题,基于广义开尔文体描述煤柱的流变特性,建立煤柱-顶板系统力学模型,结合最小势能原理,得出采空区煤柱的有效承载时间计算公式,并依据公式对影响煤柱承载时间的影响因素进行了分析,最后结合工程实例进行验证。结果表明:采空区煤柱-顶板系统将随时间逐渐破坏至失稳;煤柱的有效承载时间与自身黏性系数成正线性关系、与瞬时弹性系数近似呈"抛物线"关系、与横截面积成正比例关系、与长期弹性系数、顶板刚度和煤柱高度近似呈负指数关系;建立的基于煤柱流变特性的采空区煤柱-顶板体系力学模型所推导出的煤柱有效承载时间计算公式具有一定的准确性。

In order to solve the wedge pillar type goaf of the coal mining face with a hard roof affected to the mining in the upper seam, based on the description on the rheological features of the coal pillar with the general Kelvin Body, a dynamics model of the coal pillar-roof system was established. In combination with the min pot ential energy principle, an effective loading time calculation formula of the coal pillar in the goaf was obtained. An analysis was conducted on the formula affected to the factors of the coal pillar effective loading time and finally in combination with the engineering cases, verifications were conducted. The results showed that the coal pilla r-roof system of the goaf would be steadily in failure and instability with the time passed. The effective loading time of the coal pillar and self viscosity cofficient would be in a positive linear relationship, would approximately be in a " parabola" relationship to the instantaneous elastic cofficient, would be in a positive proportion relatio nship to the cross section area and would approximately be in a negative index relationship to the long term elastic coefficient, roof rigidity and coal pillar height. The es tablished mechanics model of the goaf coal pillar-roof system based on the rheological features of the coal pillar could derive the calculation formula of the coal pillar ef fective loading time with certain accuracy.

国家科技重大专项资助项目(2016ZX05045007-003)；中国煤炭科工集团科技创新基金面上资助项目(2016MS011)；