工程建设条件下小煤窑采空区场地稳定性评价  

Stability Evaluation of Small Coal Mine Goaf Site under Engineering Construction Conditions

作　　者：胡应全 王刘文 陈金宏 王彤标 李彬 HU Yingquan;WANG Liuwen;CHEN Jinhong;WANG Tongbiao;LI Bin(Guizhou Coal Mine Design and Geological Engineering Co.,Ltd.,Guiyang,Guizhou 550025;Guizhou Coal Mine Design Research Institute Co.,Ltd.,Guiyang,Guizhou 550025)

机构地区：[1]贵州煤设地质工程有限责任公司,贵州贵阳550025 [2]贵州省煤矿设计研究院有限公司,贵州贵阳550025

出　　处：《中国煤炭地质》2024年第12期56-61,69,共7页Coal Geology of China

基　　金：贵州煤设地质工程有限责任公司创新项目(GMS-RD2023.KJ-002号)。

摘　　要：随着矿区土地资源破坏、城镇化建设用地紧张等问题日渐突出,在采空区上方兴建建(构)筑物不可避免。其中小煤窑采空区形成的不良地基对工程建设具有重大影响,对其进行稳定性评价显得尤为重要。首先采用AHP方法分析了工程建设条件下小煤窑采空区稳定性主要影响因素,再从力学解析的角度对其评价方法进行了研究。结果表明,工程建设条件下小煤窑采空区稳定性主要影响为采空区埋深、建筑荷载以及煤岩柱安全稳定性。为计算出工程建设条件下的煤(岩)柱安全稳定性系数,在原有规范推荐公式的基础上添加建构筑物引起的附加荷载并推导出了新的计算公式。在评价地基稳定性时,对现有公式进行修正,认为巷道顶板的埋藏深度应为基础底面至巷道顶面的距离而非地面至巷道顶面的距离,应采用等效内摩擦角而非内摩擦角,上部荷载应采用基底压力而不是附加应力,同时为方便运用,添加覆岩安全稳定系数计算公式。实际案例证明修正后的荷载临界影响深度判别法适用于评价小煤窑采空区稳定性,相对未修正前的公式,既达到了安全可靠,又避免了过于保守而加大地基处理费用。With the increasingly prominent problems such as the destruction of land resources in mining areas and the shortage of land for urbanization construction,it is inevitable to build buildings above the goaf.The poor foundation formed in the goaf of small coal mines has a significant impact on engineering construction,and it is particularly important to evaluate its stability.Firstly,the AHP method was used to analyze the main influencing factors on the stability of small coal mine goaf under engineering construction conditions,and then the evaluation method was studied from the perspective of mechanical analysis.The results indicate that the stability of small coal mine goaf under engineering construction conditions is mainly affected by the buried depth of the goaf,building loads,and the safety and stability of coal-rock pillars.To calculate the safety and stability coefficient of coal-rock pillars under engineering construction conditions,additional loads caused by building structures were added on the basis of the recommended formula in the original specifications,and a new calculation formula was derived.When evaluating the stability of the foundation,the existing formula is modified to consider that the buried depth of the roadway roof should be the distance from the foundation bottom to the roadway roof rather than the distance from the ground to the roadway roof.The equivalent internal friction angle should be used instead of the internal friction angle,and the upper load should be based on the foundation pressure rather than additional stress.At the same time,for ease of use,a formula for calculating the safety and stability factor of the overlying strata is added.The actual case proves that the modified method for determining the critical depth of load influence is suitable for evaluating the stability of small coal mine goaf.Compared with the uncorrected formula,it not only achieves safety and reliability,but also avoids being too conservative and increasing the cost of foundation treatment.

关 键 词：工程建设 地基稳定性评价 小煤窑采空区 AHP 力学解析法 

分 类 号：P642.21[天文地球—工程地质学]