荷载临界影响深度法在小煤窑采空区场地稳定性评价中的运用

Stability Evaluation of Mined Voids in the Small Coal Mines for the Proposed Engineering Construction Conditions

我国煤炭工业发展已久,电力工程、公路、铁路、水利工程等建(构)筑物不可避免地兴建在煤矿老采空区上方。其中小煤窑采空区资料缺乏、开采深度小、分布复杂、隐蔽性高的特点使得其对工程建设产生很大的影响。基于现阶段小煤窑采空区稳定性分析计算方法尚不成熟,目前工程中常用荷载临界影响深度法进行小煤窑采空区场地的稳定性评价,但其计算参数的物理意义在各技术规范中不一致。采用力学平衡分析从力学原理出发推导荷载临界影响深度法的计算公式,明确其各参数的物理力学意义,并在实际工程案例中得到运用,可为类似工程提供借鉴。

China’s coal industry has for a long history.The power engineering,highway,railway,water conservancy projects and other structures are inevitably constructed above the coal mines with mine voids.The characteristics of mined voids in the small coal mines,such as,lack of historical mining data,small mining depth,complex distribution and high concealment,have potentially great influence on proposed engineering constructions.Since the current small coal mined void stability analysis method is not mature,the current engineering load critical influence depth method is commonly used to evaluate the stability of the small coal mine site,but the physical significance of the engineering parameters is inconsistent with the various technical specifications.In this paper,the mechanical balance analysis is adopted to derive the formula of load critical influence depth method from the mechanical principles.The physical and mechanical significance of each parameter is clarified.