基于非线性统一强度理论下的边坡稳定性极限平衡分析

发布时间：2019-01-05 09:57

【摘要】：在边坡稳定性分析中,常采用的强度准则一般较少考虑中主应力对边坡破坏效应的影响,然而岩体的实际应力状况表明中主应力存在,且中主应力对边坡岩体的强度潜能发挥起着重要作用。基于考虑中主应力的统一强度理论下的Hoek-Brown(简称H-B)准则,通过对滑动面上的应力进行假设,并采用泰勒级数简化统一强度理论下的H-B准则表达式,然后根据滑动体满足所有静力平衡条件求解滑动面上的应力,进而得到边坡的安全系数。当中主应力影响系数b=0时(即为基本H-B强度准则),与等效的线性Mohr-Coulomb(简称M-C)强度准则下的瑞典法1、简化Bishop法、Spencer法和Morgenstern-Price(简称M-P)法以及基于统一强度理论下的瑞典法2进行算例对比分析,验证了方法的可行性。同时,以边坡的坡高H、坡角β和b为变量进行参数分析,研究表明:b增大(即中主应力对边坡的破坏效应影响越大)时,计算所得的安全系数增大,由此表明基本H-B强度准则下分析所得的边坡稳定性偏于安全。另外,由于提出的方法能够满足滑动体的所有静力平衡条件,且对未考虑条间作用力影响所得滑动面上的初始正应力进行了修正,故此方法较瑞典法2所得结果要大且更为严格。
[Abstract]:In slope stability analysis, the commonly adopted strength criterion seldom considers the effect of medium principal stress on slope failure. However, the actual stress condition of rock mass shows that the medium principal stress exists. And the medium principal stress plays an important role in the strength potential of slope rock mass. Based on the Hoek-Brown (H-B) criterion under the unified strength theory considering the principal stress, the stress on the sliding surface is assumed, and the H-B criterion expression under the unified strength theory is simplified by Taylor series. Then the stress on the sliding surface is solved according to all the static equilibrium conditions of the sliding body, and the safety factor of the slope is obtained. The influence coefficient of principal stress (b = 0) (i.e. the basic H-B strength criterion) is compared with the Swedish method under the equivalent linear Mohr-Coulomb (M-C) strength criterion, and the simplified Bishop method is used. The Spencer method and Morgenstern-Price (M-P) method, as well as Sweden method 2 based on unified strength theory, are compared and analyzed to verify the feasibility of the method. At the same time, the parameter analysis of slope height H, slope angle 尾 and b is carried out. The results show that the calculated safety factor increases with the increase of b (that is, the greater the influence of medium principal stress on the slope failure effect). The results show that the slope stability obtained by H-B strength criterion is more safety than that of safety. In addition, the proposed method can satisfy all the static equilibrium conditions of the sliding body, and the initial normal stress on the sliding surface is modified without considering the influence of the interbar force on the sliding surface. Therefore, the result of the method is larger and more strict than that obtained by Swedish Law 2.
【作者单位】：中南大学土木工程学院;
【基金】：教育部博士研究生学术新人奖项目(No.114801045) 湖南省研究生科研创新项目(No.CX2012B056) 贵州省交通运输厅科技项目(No.2010-122-020)
【分类号】：TU45

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