旺格维利采煤法采空区煤柱-顶板受力模型与数值模拟

Mechanics analysis and numerical simulation of coal pillar and stiff roof in Wongawilli goaf

本文以榆神矿区常家梁煤矿为研究背景,对旺格维利采煤法的煤柱-顶板受力机理进行研究。通过建立力学结构模型和数值模拟的方式,分析顶板和煤柱在简化的力学模型中的内力情况和在数值模拟中的应力分布和塑性区分布情况。煤柱-顶板力学模型计算得出顶板的弯矩图、剪力图和煤柱的应力,假设煤柱受力均匀,煤柱承受的平均应力为8.7 MPa;数值模拟结果得出应力和塑性区分布图,可以看出此种开采方案下,刀间煤柱进入塑性区,失去承载能力,巷间煤柱处于稳定状态,顶板荷载主要由巷间煤柱承担;数值模拟结果验证了力学模型的合理性,并且通过对比分析得出理论计算的巷间煤柱应力比模拟结果大,这是因为理论模型将刀间煤柱的约束作用和部分承载能力进行了简化。

This paper mainly studies the stress mechanism of coal pillar and stiff roof by Wongawilli mining method,in the background of Yushen mining area Changjialiang coal mine. Through establishing the model of mechanical structure and the numerical simulation,we analyze the internal force of roof and coal pillar in simplified mechanical model,study stress distribution and plastic zone distribution in numerical simulation. The mechanical model of coal pillar and stiff roof can conclude the bending moment diagram,shear diagram and the stress of coal pillar,assuming that the coal pillar suffered uniform power,the average stress of coal pillar is 8. 7 MPa. The numerical simulation shows the stress and plastic zone distribution,we can conclude that in this mining method,coal pillars between the cuttings will turn into plasticity and lose the bearing capacity,the coal pillars along the tunnel is in a stable state,the loading of roof is mainly borne by the coal pillars along the tunnel; The numerical simulation results prove the validity of the mechanical model. The comparison between theoretical calculation and numerical simulation supports that the coal pillars along the tunnel stress given by theoretical calculation is lager than the numerical simulation,because in theoretical calculation,the constraint function and load capacity of the coal pillar between the cuttings are simplified.