In this present study, a twice-peeling model was established to analyze the hyperbolic coal pillars stability in underground coal gasification and then propose the concept of stripping degree to show model details for numerical simulation. The data shows that hyperbolic coal pillars stability can be analyzed through the twice-peeling model. Considering the coal pillars peeling and high temperature effects, one side of coal pillars will decrease 3 m, and the stability coefficient is 1.6 which has enough bearing capacity. When the arch depth ratio is 0.6, the critical condition for the coal pillar instability is reached. In this paper, underground coal gasification industrial test area still had strong bearing capacity after twice stripping, and there was no sudden instability. The research results can provide reference for the gasifier design and the stability of non-uniform coal pillars in the future.

中文翻译：

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具有剥落和高温效应的双曲线煤柱稳定性分析

在本研究中，建立了二次剥离模型来分析地下煤气化过程中双曲线煤柱的稳定性，然后提出剥离度的概念以显示模型细节以进行数值模拟。数据表明，双曲线煤柱稳定性可以通过二次剥皮模型进行分析。考虑到煤柱剥落和高温影响，煤柱一侧减少3 m，稳定系数为1.6，具有足够的承载能力。当拱深比为0.6时，达到煤柱失稳临界条件。本文中，煤炭地下气化工业试验区经过两次剥离后仍具有较强的承载能力，未出现突然失稳现象。