条带开采尺寸设计的滑移线法

The Sliding Line Method Used for Design of Strip Mining

本文根据理想刚塑性平面问题的滑移线理论,以5°角差作出了条带煤柱的滑移线网,得出了煤柱不同宽高比α/m情况下的整体极限强度,给出了条带开采尺寸设计的滑移线法。通过分析比较认为,冒落条带开采时,若采深较小,应采用安全系数为2.0的滑移线法或单向应力法;若采深较大,可采用安全系数为1.8～2.0的滑移线法;而在中等采深的条件下,可采用安全系数为1.5～1.7的滑移线法或三向应力法,三向应力法的安全系数可取为1.5。

According to the sliding line theory of the two-dimensional ideal rigid-plastic problem, the sliding line net of the strip pillar is drawn in this paper, in which the difference of two angles between horizontal line and adjacent sliding lines is 5 degrees. The integral limit strengths of coal pillars with various ratios of width to height a/m are obtained, and the sliding line method for designing the scheme of strip mining is given. After analysing and comparing, the sliding line method with other methods, the author recommends that in designing caving strip mining if mining depth H≤ 100m, the slip line method with safety cofficient 2.0 or the uniaxial stress method should be used; if the mining depth H≥300m, the strip line method with safety coefficient 1.8-2.0 should be used; and in the case of 100< H< 300m the slip line method with safety coefficient 1.5-1.7 or the three-directional stress method with safety coefficient 1.5 should be used.