普通混凝土矸石带联合巷帮支护沿空留巷试验

Test of ordinary concrete and waste-rock band for roadside supporting in gob-side entry retaining

基于薄煤层厚灰岩顶板沿空留巷矿山压力显现规律,论证了采用普通混凝土矸石带联合巷帮支护沿空留巷的可行性,采用FLAC3D模拟分析了3个支护方案的留巷效果。通过建立顶板断裂的力学模型,提出临界悬臂梁的概念,并以此为基础得出充填体切断顶板需要的支护阻力和宽度。实践表明,采用矸石带支护初期顶板,有效控制了顶板初期下沉,有效弥补了混凝土初凝时间长和初凝强度低的缺点,采用混凝土作为充填体材料,很好地适应了采空区厚灰岩顶板岩层的运动,达到预期的留巷效果。

Based on the movement law of roof strata and deformation characteristics,the feasibility of the ordinary concrete and the waste-rock band for roadside support is analyzed using FLAC3 Dsimulation,and the effect of the 3 support schemes of the gob-side entry retaining is analyzed. By establishing the mechanical model of roof fracture,the concept of the critical cantilever beam is put forward,and the supporting resistance and width are obtained. The practice shows that the initial period of the roof is effectively controlled by use of the waste-rock band,which effectively compensates the shortcomings of the initial setting time of concrete and the low initial setting strength. Using concrete as the filling material,it is well adapted to the movement of the thick gray rock in the goaf.