动静组合加载下岩石-充填体破坏特征研究

充填法开采时,爆破扰动势必对充填体造成不同程度的破坏,为更好地保护充填体稳定,需要对其破坏模式进行研究,并明确其破坏程度。从矿山实际出发,制备岩石-充填体组合试件,对其开展动静组合加载实验。研究结果表明,轴向载荷的施加与否会导致岩石-充填体试件的破坏模式发生变化。当不施加轴压时,试件更容易发生拉伸破坏。当施加一定轴压时,由于端部效应的影响,试件充填体部分的破坏模式由拉伸破坏向压剪破坏转变。这也进一步造成充填体破坏程度的变化,随着轴向压力的增加,其破坏程度逐渐减弱。说明拉伸破坏会对充填体造成更为严重的破坏,相较于拉伸破坏,压剪破坏造成的充填体破坏程度较低。

When mining by filling method,blasting disturbance is bound to cause varying degrees of damage to the filling body.In order to better protect the stability of the filling body,it is necessary to study its failure mode and clarify its damage degree.Based on the actual situation of the mine,the combined specimen of rock and filling body was prepared,and the dynamic and static combined loading experiment was carried out.The results of the study show that the application or non-application of axial load leads to a change in the damage pattern of rock-fill specimens.When no axial pressure is applied,the specimen is more prone to tensile damage.When certain axial pressure is applied,the damage mode of the filler part of the specimen changes from tensile damage to compression-shear damage due to the end effect.This further results in a change in the degree of damage of the backfill,which gradually decreases with the increase of axial pressure.Tensile damage causes more severe damage to the backfill,and compression shear damage causes less damage to the backfill compared to tensile damage.