软岩巷道围岩变形与分区控制技术研究

Surrounding Deformation and Zoning Control Technology of Soft Rock Roadway

复杂地质条件下软岩巷道围岩稳定控制是技术性难题。以现场实测为主、理论分析为辅的研究方法,构建了非等压巷道围岩弹性-损伤力学模型,对荣华矿西翼运输大巷围岩变形特征及控制方法进行了研究。研究结果表明:断层形成后,水平应力和初始水平应力比值为4.3~8.5;较小的内摩擦角、内聚力及较大的侧压系数对应较大的塑性区半径及较高的蝶形塑性区概率,塑性区半径扩展速度可间接表征蝶叶塑性区是否形成;对于易松动软岩,应在支护初期保持支护阻力及改善围岩性质;巷道前方水平裂隙较为发育,围岩整体变形量较小,两帮移近量和顶板下沉量分别在150 mm、40 mm以内,验证了分区支护策略及支护参数的合理性。

The stability control of surrounding rock in soft rock roadways under complex geological conditions is a technical challenge.The elastic damage mechanics model of surrounding rock of non-isobaric roadway was constructed based on the research method of field measurement and theoretical analysis,and the deformation characteristics and control methods of surrounding rock of transportation roadway in the west wing of Ronghua Mine were studied.The results are concluded as follows.Firstly,after the formation of the fault,the ratio of horizontal stress to initial horizontal stress is 4.3-8.5.Secondly,the smaller internal friction angle,smaller cohesive force,and larger lateral pressure coefficient correspond to a larger plastic zone radius and a higher probability of butterfly shaped plastic zones.The expansion speed of the plastic zone radius can indirectly characterize the formation of butterfly shaped plastic zones.Thirdly,for easy-loosening soft rock,the support resistance should be maintained and the properties of the surrounding rock should be improved in the initial stage of support.Finally,the horizontal cracks in front of the roadway are relatively developed,and the overall deformation of the surrounding rock is relatively small.The displacement of the two sides and the subsidence of the roof are within 150 mm and 40 mm,respectively,which verifies the rationality of the zoning support strategy and support parameters.