小曲率拱型支架支护系统理论与试验分析

针对煤层顺槽梯形支架存在的问题,提出一种新型结构的小曲率拱型支架。采用曲梁模型进行了支架系统的受力分析,得到其最大承载能力;通过与直梁支架承载能力相比较,得到了小曲率拱型支架承载能力系数与曲梁跨度和半径的影响关系。同时进行了地面试压和井下支护工程实验。结果证明:小曲率拱型支架力学性能远优于梯形支架,支撑能力大,自身稳定性良好,有效解决了近距离和下分层煤层巷道不可锚且在强压下难支护的问题。

Theoretic Analysis and Experiment on Arch Support System with Small Curvature

In view of the problems occurring in trapezoidal support used in coal seam gateway, a novel small - curvature arch support for mining engineering is presented. The maximal load - carrying capability of the arch support is calculated by adopting mechanical model of curved beam based on its force analysis, and relationship between bearing capacity coefficient of small curvature arch support and radius and span of curved beam is gained based on supporting capacity comparison of curved-beam and straight beam. Its corresponding experiments have been done on ground surface and in underground in - situ engineering, respectively. It is shown that small - curvature arch support is very superior to trapezoidal support in mechanical properties, and has higher bearing capacity and better self - stability, so that such problem as short - distance coal gateways and lower branch coal gateways can not be bolted and is difficult to support in high pressure can be solved effectively.