巷道支护力作用及影响因素分析

The Effect of Roadway Supporting Forces and Analysis of Its Influence Factors

采用库伦-莫尔理论，对巷道圃岩出现塑性区前后支护力与圆岩应力之间的关系，以及不同塑性区力学参数下支护力与巷道围岩塑性区半径之间的关系进行了研究。结果表明，由于巷道实际支护力与原岩应力比值只有1／10～1／100，对不出现塑性区和破裂区的完整岩体巷道，支护力的作用是很小的，可以忽略不计。而当围岩中出现了塑性区和破裂区之后，支护力的作用才开始显现。提高支护力可直接减小圃岩破裂区（塑性区）范围，但提高支护力的主要作用是提高弹塑性区围岩压应力，达到提高破裂区（塑性区）岩体宏观强度的目的，从而减小塑性区和破裂区的范围。影响支护力作用效果的主要因素是塑性区力学参数。

With the Mohr-Coulomb criterion, the relationship between the roadway supporting force and the stress of surrounding rock, and the relationship between the roadway supporting force and the radius of plastic zone with different rock mechanical parameters were analyzed before and after the emergence of the plastic zone in surrounding rock. The studies show that when the surrounding rock has not been damaged, the effect of supporting force is slight, even can be neglected because the actual supporting force is only 1/10-1/100 of original rock stress, but after the surrounding roek has been damaged, the effect of supporting force begins to appear. The studies also show that the increased supporting force can reduce the radius of the fraetural zone （plastic zone） in surrounding rock derectly, but the main effect of the increased supporting force is to improve the compressive stress on rock in elastoplastic region, and to increase the rock strength of whole fraetural zone （plastic zone） so as to reduce the ,scope of fractural zone （plastic zone）. The main factors that influence the effect of supporting force are the mechanical parameters of surrounding rock in plastic zone.