板裂介质岩体边坡的后屈曲性态

Post-buckling Behavior of Rock Mass Slope with Sheet Crack

应用板裂边坡介质力学计算模型,在边坡岩体屈曲性态和变形因素分析的基础上,研究了层状边坡在分叉点附近的邻域,探讨了结构分叉后平衡路径的演化途径;应用后屈曲能量准则建立的平衡稳定模态幅值方程,充分考虑屈曲岩层自重的法向分力对边坡稳定性的影响,得到一般情况下板裂介质岩体边坡溃屈极限长度方程;给出了任意倾斜角度边坡溃屈极限长度和模态幅值的极值,并以此作为岩体边坡稳定性的位移判剧.研究表明:分叉点附近的邻域与边坡坡角、岩体材料及结构几何特征有关;边坡从初始屈曲到后屈曲的变形过程中,只有当正则因子改变正负号时,系统才会从一个状态突跳至另一个状态;而由坡角确定的剖分因子始终控制着系统状态变量与载荷的对应关系,并有利于边坡岩体结构的稳定.图1,参12.

Based on mechanical calculation model of sheet slope crack, the regions nearby equilibrium bifurcation point and evolutions along equilibrium path were investigated by analyzing the buckling behavior and deformation factors of side slopes. First, the equation for limit length of slope buckling failure in all cases, considering the component vertical to rock layer due to gravity, was established by using medality amplitude equation of equilibrium stability derived by post- buckling energy criterion. Then, the buckling limit length and extremum for modality amplitude serving as stability displacement for any angle slope of inclination were given through the equations for modality amplitude and limit length of slope buckling failure. It is shown that the stabile regions nearby bifurcation point have relations with the angle of bedding slop, the material of rock mass and the geometrical properties. In the process of side slope deformation from initial buckling to post- buckling, only ff canonical factor changes its plus-minus, does the system jump from one state to the other state. The ripping factor depending on bedding slope angle can determine singlevatued relation between the state variate and load, and also benefits to the stability of reck mass slope with sheet crack. 1fig., 12refs.