露天矿顺层蠕动边坡稳定性动态分析探讨

DYNAMIC ANALYSIS OF STABILITY OF BEDDING CREETING TYPE SLOPE AT AN OPEN PIT COAL MINE

进行了阜新海州露天矿北帮东部一号断层区顺层蠕动边坡变形、失稳机理分析讨论。根据老化理论提出了软弱夹层的一般流变方程τ =Ao( 1+δ·tα) ·γm ( 1+σmH) ,确定由等速蠕变向加速蠕变过渡的临界应变量作为破坏时刻的破坏应变量γs,从而建立长期抗剪强度与应力作用时间变化的关系τ =Ao·γs( 1+δ·tα) +Ao·γsH ( 1+δ·tα) ·σm=c +σm·tgφ ,对于非稳定蠕动变形 ,等速蠕变阶段的应变速率与剪应力超过长期极限强度的程度有关 ,在此基础上探讨并建立顺层蠕动边坡的流变稳定性分析方法 ,评价蠕动边坡变形。

The non linear creep property of the weak layer is analyzed and the change property of its mechanics strength and the non linear property of its stress strain relationship are indicated.On the basis of the aged theory,a common creep equation- τ=A o(1+δ·t α)·γ m(1+σ mH)is posed.Subsequently,the damage strain γ s is defined as critical value from the steady state creep rate to the increasing state creep rate,and the relationship between the long term shear strength and the stress changing rate with time- τ=A o·γ s(1+δ·t α)+A o·γ sH(1+δ·t α)·σ m=c+σ m·tgφ is concluded.As to the instability deformation of the creeping slope,the strain rate of the steady state creep is associated with its shear stress level to exceed its shear strength limit.The property studies show that the shear strength of the weak layer decreases with time so provide an important basis for the theory analysis of the dynamic stability on the wriggling slope.