直边坡参数对边坡稳定性的影响

采用量纲分析的方法给出直边坡几何参数和物理力学参数决定边坡稳定系数的通式。首先,边坡高度H和边坡角α被确定为直边坡的几何参数,抗拉强度σt、黏聚力C、内摩擦角和岩土比重γ被确定为直边坡的物理力学参数;其次,采用量纲分析的方法,形式上给出边坡稳定系数F的通式,F=qαpα(C/Hγ)pcφpφ(σt/Hγ)pσ;再次,为了得到待定系数q和待定指数pα、pc、pφ、pσ,通过最小二乘法对数万个计算结果进行回归分析(每个结果都是通过FLAC计算将确定的直边坡参数与它的稳定系数形成对应)。结果表明,在一定的取值范围内,边坡稳定系数的表达式为F=4.63/α(C/Hγ)0.17φ0.83。可见,受MohrCoulomb和拉应力两个强度准则控制的岩土材料形成的直边坡的稳定性受无量纲的黏聚力、边坡角(角度)、内摩擦角(角度)的控制,与抗拉强度关系不大。无量纲黏聚力是黏聚力除以边坡高度和岩土比重。

Effect of the straight-linear slope parameters on the slanting stability

The paper is engaged in a study for the effects of the straight-linear slope parameters on the slanting stability.For the said purpose,we have first of all managed through a dimensional analysis to obtain a general formula,which is meant to represent the relation between the factor of the stability of straight slope and its geometric and mechanical parameters.In proceeding with the analysis,we have first of all,identified the slope height H and the slope angle α of the equation as the geometric parameters of a straight slope,the tensile strength σt,the cohesion C,the internal friction angle φ and the specific gravity of the said slope γ as the physical and mechanical parameters of a straight slope.And,secondly,we have developed a form of formula of slope stability has been given viafactor while the F =qαpα(C/ Hγ)Pc (σt/Hγ)Pφthe dimensional analysis.And,thirdly,in order to gain the values of undetermined coefficients q and undetermined exponents Pα,Pc,Pφ,,Pσ,we have done a regression analysis through tens of thousands of calculation with the method of the least squares (each result accounts for a corresponding one between the straight slope parameters given and the stability factor gained through the FLAC calculation).The final results demonstrate that the slope stability factors can be denoted within a certain range,while the formula represented by the factors of stability of the straight slope can be identified and discriminated by the three dimensionless parameters,i.e.the dimensionless cohesion,the internal friction angle (degree),and the slope angle (degree).However,the factor of stability of straight slope can be found unrelated to the tensile strength,whereas the dimensionless cohesion can be used to imply the cohesion between the slope height and the specific gravity of the said slope.