【作者】 王勇；

【导师】 曹树刚；

【作者基本信息】 重庆大学 ， 采矿工程， 2012， 硕士

【摘要】 本文通过理论分析，建立了倾斜煤层沿空留巷力学结构模型，分析了分别采用机巷和风巷沿空留巷时顶板前期和后期对巷旁支护的作用规律，并通过力学求解得到相应条件下的巷旁支护阻力求解公式。根据求解公式，选取不同的支护宽度，计算出相应的巷旁支护阻力，以此选择合适的巷旁支护方式和支护体尺寸。运用三维数值模拟软件FLAC3D，分别建立了机巷和风巷沿空留巷的三维数值分析模型，分析了不同的支护宽度和支护材料对沿空留巷围岩控制效果，同时对比分析了机巷和风巷沿空留巷时的围岩应力及位移分布。结果表明，采用风巷留巷时巷旁支护体内部和煤帮深处约等于巷道宽度范围内出现较大应力集中；而采用机巷留巷时，应力集中主要出现在煤帮深部，巷旁支护体内部应力相对较小。就其原因，主要受煤层倾角的影响，采用风巷留巷时，顶板重力分量力矩有利于顶板岩层回转下沉，导致顶板下沉量比机巷留巷时大，故其巷旁支护体内部及煤帮深部应力集中程度也较高。根据理论计算结果，对“三软”煤层条件下的叙永煤矿S1136工作面回风巷和威鑫煤矿11902工作面机巷进行了沿空留巷巷旁支护方案设计。巷内已采用锚杆+锚网索+喷浆联合支护，S1136风巷巷旁采用矸石装袋堆码4m宽的支护带，11902机巷巷旁前100m采用砌筑3m宽的预制混凝土块墙支护，余下部分拟采用柔性模袋+泵送矸石混凝土充填1.5m宽支护。利用矿山废弃矸石作为充填骨料进行了泵送矸石混凝土的配比试验研究，结果表明，采用1.0%掺量的高效泵送剂能有效改善混凝土的和易性，显著提高塌落度和流动性，同时能加快混凝土凝结，提高早期强度；矸石混凝土的强度随水灰比的降低而增大，通过标准试件单轴抗压强度试验表明，采用0.5水灰比，单位体积混凝土水泥用量为450kg/m3时，其3d、7d和28d抗压强度分别达到7.6MPa、13.7MPa和20.8MPa，满足现场充填强度要求。以此确定了满足泵送性能及强度要求的矸石混凝土合适配比。现场工业性试验表明，采用矸石装袋堆码支护方式，由于支护体可缩性较大，故前期顶板下沉量也较大，但随着矸石压实，强度增高，顶板下沉逐渐趋于平稳。该支护方式基本能满足巷道支护要求，但巷道整体下沉量较大，需要采取一定的修复措施；采用砌筑预制混凝土块墙支护方式，由于预制块强度高，前期顶板控制良好，但由于支护体没有足够的可缩量适应顶板下沉，随着工作面推进，老顶回转下沉导致支护体内部应力集中，最终使支护体出现裂纹直至破坏，引起留巷后期顶板下沉严重。为此，下一步拟采用柔性模板+泵送矸石混凝土充填支护方式。综合研究表明，柔性模板+泵送矸石混凝土充填支护方式结合了以上两种支护方式的优点，且机械化程度高，作业人员的劳动强度低，适应矿井高产高效的需求。更多还原

【Abstract】 This article through the theoretical analysis， a mechanical structure model ofinclined coal seam on gob-side entry retaining was set up， and earlier stage and laterstage rules of roof rock effect to the roadside support on conveyor roadway andventilation roadway gob-side entry retaining was respectively analyzed， the roadsidesupport resistance calculation formula on corresponding condition of gob-side entryretaining have been gained by the mechanics solution. According to the solutionformula，the selection of different support width，calculate the corresponding roadsidesupport resistance， thus choose the right roadside supporting method and determinedby supporting body size.According to the theoretical calculation results， design the roadside supportprograms of gob-side entry retaining for the XuYong coal mine S1134ventilationroadway and the WeiXin coal mine11902conveyor roadway with mining "three soft"coal seam. It has been combined supported with anchor+cable anchor+gunite in theroadway. and that stacked4m wide support body in the S1134ventilation roadside.Then mason3m wide support wall with precast concrete block in11902conveyorroadside. Rest to using the flexible template+pumping gangue concrete filling1.5mwide support. The proportioning tests of pumping concrete with mining waste gangue asaggregate were researched. It effectively improved the workability， greatly raised thecollapsed slump， and reduces the concrete set time and raises its forepart strength ofthe pumping concrete with1.0%mix amount the pumping aid. The concrete strengthincrease with water cement ratio decreases， but too much cement mix amount will leadto the higher cement hydration heat， so that the concrete will crack as its internaluneven contraction. Through the experiment， determined to meet the requirements ofthe pumping and strength gangue concrete filling materials， make full use of themining waste gangue， realize the comprehensive utilization of resources.Using three-dimensional numerical simulation software， the surrounding rockstress distribution and deformation in different supporting conditions on gob-side entryretaining were numerical simulation calculated.3D numerical simulation models onconveyor roadway and ventilation roadway gob-side entry retaining were respectivelyset up and calculated， the result show that，stress concentration appears both in theinternal roadside support body and the coal side deep within equal to the width of roadway on ventilation roadway gob-side entry retaining， and that stress concentrationappears only in the coal side deep， in the roadside support body is much lower. Mainbecause of that is affected to the angle of coal seam， it enhances the rotary andsubsidence of roof as its dead weight， lead to the subsidence is higher than conveyorroadway gob-side entry retaining， which result in the stress concentration onventilation roadway gob-side entry retaining is higher than conveyor roadway’s.Through the industrial test it shows that when uses the stacking bagging ganguesupporting method， the roof subsidence is high because of the bagging gangue haslarge shrinkage， and its strength is strengthened with the bagging gangue iscompacted， as a result the subsidence of roof tend to stationary. This support methodsubstantially meet the requirement of the roadway support， but it still need somerestoration measures for the high subsidence. When uses the masonry precast concreteblock method， because its high strength， the roof is controlled well in forepart， butit has not enough subsidence to adapt the rotary and subsidence of roof， due to thestress concentration in the support body is overload， lead to the support body iscrazed even destroyed， result in the roof has large subsidence in late stage. Thissupport method substantially meet the requirement of the roadway support， but it stillneed some restoration measures for the high subsidence.When uses the masonry precast concrete block method， because its high strength，the roof is controlled well in forepart， but it has not enough subsidence to adapt therotary and subsidence of roof， due to the stress concentration in the support body isoverload， lead to the support body is crazed even destroyed， result in the roof haslarge subsidence in late stage. Therefore， it plan to use the support method of flexibletemplate and pumping gangue concrete， the method unite the advantages of the bothsupport methods， and mechanization， high efficiency， low labor intensity，accommodate the requirement of high production and high efficiency.更多还原