Xiaochuan Wang, Wei Wang, Zhaolong Ge, Man Wang, Chaoyu Xu
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引用次数: 0
Abstract
To better understand the strain‐softening effect and its implications for coal construction and extraction, this paper utilizes a numerical simulation method to investigate the deformation stability of gas extraction holes with consideration for strain softening. The study further analyzes the strain‐softening effect on effective stress, gas pressure, and plastic failure mode by comparing models with and without considering this effect. The results show that the plastic failure mode in the area close to the hole wall is mainly tensile shear combination failure. Shear failure occurs at the intersection angle of the X‐type shear zone and both the left and right sides, whereas tensile failure more likely occurs on the upper and lower sides due to shrinkage collapse. The displacement of coal increases with extraction time and stabilizes, along with the maximum effective stress concentration area and the plastic damage area. The strain softening process can negatively affect the extraction hole by increasing the displacement of coal, intensifying stress concentration, and exacerbating gas silting near the hole wall, ultimately hindering gas extraction efficiency. Also, faults and weak interbeds can further destabilize the extraction hole.
为了更好地理解应变软化效应及其对煤炭建设和开采的影响,本文利用数值模拟方法研究了考虑应变软化的瓦斯抽放孔的变形稳定性。研究通过对比考虑和未考虑应变软化效应的模型,进一步分析了应变软化效应对有效应力、瓦斯压力和塑性破坏模式的影响。结果表明,靠近孔壁区域的塑性破坏模式主要是拉伸剪切组合破坏。剪切破坏发生在 X 型剪切带与左右两侧的交角处,而拉伸破坏由于收缩塌陷更可能发生在上下两侧。煤的位移随着开采时间的延长而增大,并与最大有效应力集中区和塑性破坏区一起趋于稳定。应变软化过程会增加煤的位移,加剧应力集中,加剧孔壁附近的瓦斯淤积,最终阻碍瓦斯抽采效率,从而对抽采孔产生不利影响。此外,断层和软弱夹层也会进一步破坏抽采孔的稳定性。
期刊介绍:
The journal welcomes manuscripts that substantially contribute to the understanding of the complex mechanical behaviour of geomaterials (soils, rocks, concrete, ice, snow, and powders), through innovative experimental techniques, and/or through the development of novel numerical or hybrid experimental/numerical modelling concepts in geomechanics. Topics of interest include instabilities and localization, interface and surface phenomena, fracture and failure, multi-physics and other time-dependent phenomena, micromechanics and multi-scale methods, and inverse analysis and stochastic methods. Papers related to energy and environmental issues are particularly welcome. The illustration of the proposed methods and techniques to engineering problems is encouraged. However, manuscripts dealing with applications of existing methods, or proposing incremental improvements to existing methods – in particular marginal extensions of existing analytical solutions or numerical methods – will not be considered for review.