沿空留巷围岩受力变形特征及支护措施

主要分析了沿空留巷围岩受力变形的特征,重点介绍了在煤矿开采过程中支护措施的重要性,它不仅能够提高煤矿的开采效率,还能减少井下矿灾易发生的问题。通过对井下沿空留巷围岩的稳定性研究,也能进一步明确变形产生的特征,并通过建立力学悬臂梁结构的模型来进一步对软弱顶板或者是厚硬顶板对沿空留巷围岩的影响进行研究,还会进一步明确产生的不同类型的应力分布区,也能对巷道支护措施进行优化。

考虑流固耦合的浅埋富水软岩隧洞稳定性分析

浅埋隧洞在开挖穿越富水软岩区域时,围岩极易发生失稳破坏,影响工程进度。以哈尔滨二甲沟水库引水隧洞某富水软岩施工段为工程背景,使用COMSOL多物理场仿真软件建立了不同流固耦合效应的隧洞三维模型,研究了2种工况下隧洞施工过程中围岩受力变形规律。结果表明,浅埋隧洞在开挖穿越富水软岩区域时,不论是否考虑流固耦合效应围岩都会发生不同程度的变形。在开挖推进距离相同的条件下,考虑流固耦合效应的隧洞模型围岩应力集中特征更明显,且数值分析计算出的变形结果与工程实测数据更接近。研究成果可为浅埋隧洞穿越富水软岩区域施工安全提供参考。

软岩小净距公路隧道设计优化及稳定性研究

小净距隧道施工一直是工程建设中的难题,尤其是不良地质条件下的隧道开挖,施工灾害问题尤为突出。为确保软岩隧道的施工安全,以某小净距公路隧道为工程背景,通过计算模拟,基于现场试验,提出地表沉降控制技术,建立优化支护结构方案。现场监测数据分析结果表明:地表沉降变形的发展表现为变形快速发展阶段、变形缓慢发展阶段和变形平稳阶段,隧道开挖对近地表围岩变形的影响范围约为2.5倍洞径。深仰拱和锁脚锚杆技术在现场实施后,测得围岩拱顶沉降和水平收敛分别控制在97.33 mm和44.23 mm,约束围岩变形效果明显,最终结构受力也较为均匀。设计优化的成功实施可为类似隧道工程提供借鉴和参考。

Study of mechanical principle of floor heave of roadway driving along next goaf in fully mechanized sub-level caving face

Abstract On the basis of analyzing floor strata mechanical circumstance of the roadway, the mechanical model was established. The relative displacement of roadway floor, narrow pillar floor coal mass and floor strata was calculated, the results showed that the high abutment pressure on coal mass beside the roadway was the main reason to lead to relative displacement of floor strata. And the roadway floor heave come mainly from three aspects. Firstly, the roadway floor strata is easily fractured by the stretch stress. Secondly, because the high abutment pressure is greater than the uniaxial compressive strength of floor strata, when the roadway floor strata are fractured, the coal mass floor strata at the same depth will be fractured, and broken rock will fluid into the open roadway. Thirdly, comparing with the coal mass floor, the roadway floor is relative ascending.