初始节理对岩体内部沉陷范围的影响研究与实验验证

RESEARCH AND EXAMINATION-VALIDATION OF EFFECT OF ORIGINAL JOINTS ON SUBSIDENCE RANGE IN ROCK MASS

采动覆岩断裂直接影响地表沉陷规律,岩体中初始节理的存在使采动覆岩断裂更加复杂,从而导致岩体内部沉陷范围更难确定。首次对岩体中初始节理对采动覆岩断裂扩展规律、采动覆岩断裂范围、采动覆岩断裂分布、岩体内部沉陷范围的影响进行系统研究,提出初始节理对采动覆岩断裂的影响作用,建立了初始节理端部附近的最大切向应力计算表达式和初始节理开裂的力学条件,为岩体内部沉陷范围的确定提供了理论依据。构造了4含有不同分布初始节理的相似材料模型,进行开挖实验,验证结果与实际吻合。

The crack of the mining-disturbed rock strata affects the law of subsidence directly. But the existence of original joints in rock mass makes the crack complicated,so that the determination of subsidence range in rock mass becomes more difficult. The effects of original joints on the expanding law of crack of mining-disturbed rock strata,the range of the crack,the distribution of crack and effect of the subsidence range in rock mass are systematically studied. The influence of original joints on the crack of mining disturbed rock strata is analysed. The formula of the maximum tangent stress nearby original joints,the theory evidence to define the range of subsidence in rock mass and the mechanics condition of the crack of mining-disturbed rock strata are given. Four stimulated material models are made,which contains original joints with different distribution. The study result is well verified with the experimental data.