问题 问答题 简答题

简述影响矿压显现的主要因素?

答案

参考答案:

影响矿压显现的主要因素有:

(1)采高与控顶距。在一定地质条件下,采高是影响上覆岩层破坏状况的重要因素之一。采高越大,控顶控顶距越大,采出的空间越大,顶板下沉即工作面的矿压显现也越严重。

(2)工作面推进速度。工作面推进速度快可在短期内降低顶板下沉量;而长期稳定在一定的推进速度时,顶板下沉速度与推进速度成正比,即推进速度快,相对顶板"悬臂梁"长,顶板下沉速度快。

(3)开采深度。开采深度直接影响原始应力大小,如在松软岩层中开掘巷道,随着深度的增加,巷道主岩的“挤压、鼓”现象将更为严重。在坚硬顶板的条件下,开采深度对工作面的顶板压力大小影响不太突出,但总体规律是采深增加支承压力必然增加,从而导致煤壁片帮及底板鼓起的机率增加。

(4)煤层倾角的影响。实际观测证明,煤层倾角对回采工作面矿山压力显现的影响也是很大的。随着煤层角增加,顶板下沉量将逐渐变小,因此,在同样的生产技术条件下,采用沿倾斜向下推的倾斜长壁工作面,与沿走向推进的工作面相比,在上覆岩层中更容易形成“钱接梁”而对工作面顶板管理有利。

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