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目前,地面建筑物下压着大量的煤炭,开采这些资源已成为愈来愈重要的问题。条带开采是建筑物下采煤的常用措施之一,为达到既要多采煤炭又要保护建筑物,首先要确定条带参数的采宽b和留宽a的问题。确定采宽b和留宽a应遵循以下原则: 1、确定采宽b是保证开采后地表不出现波浪式的移动变形。 2、从总体上做到采宽b与留宽a比例适当,应使采出率不超过70%,使所留煤柱能有效的支撑顶板以减小地表变形。采宽b一般是根据经验确定的,认为b值可在H/4～H/10范围之内选取,但还应考虑回采工作面初次来压步距,在初次来压前就结束工作面,以有利于顶板管理。如果采宽较大时,应在周期来压之前
At present, a large amount of coal is pressed on ground structures and exploitation of these resources has become an increasingly important issue. Strip mining is one of the commonly used measures for coal mining under buildings. In order to achieve both coal mining and building protection, we must first determine the width b and width a of the strip parameters. To determine the width b and width a should follow the following principles: 1, to determine the mining width b is to ensure that the mining surface after the wave-free movement of deformation. 2, Generally speaking, the width b and the width a should be properly proportioned, so that the recovery rate should not exceed 70%, so that the remaining coal pillar can effectively support the roof to reduce the surface deformation. Mining width b is generally determined empirically, that the b value can be selected within the range of H / 4 ~ H / 10, but should also consider the first time mining face pressure step, the first time before the pressure to end face, To help the roof management. If the larger bandwidth, should be in the cycle before the pressure