基于块体单元法的岩石边坡安全系数研究

岩石边坡因其结构面数量众多、块体系统及其滑动方式复杂，给危险块体组合的搜索及其安全系数计算带来很大困难。基于块体单元法，对岩石边坡中的危险块体组合搜索及其安全系数的计算方法进行了研究。首先，在块体元强度折减计算的成果下，根据屈服面贯通理论提出搜索危险块体组合的新方法；然后，对安全系数计算方法进行研究，建议在位移突变判据下采用双线性交叉法计算安全系数；最后，进行了单面、双面和多面滑动以及复杂块体系统的算例分析，并与刚体极限平衡法计算结果进行了对比。结果表明，由于块体单元法考虑了力与力矩的平衡及结构面上应力的非均匀分布，其计算结果更准确。该方法有望广泛应用于复杂岩石边坡稳定分析。

Research on safety factors of rock slopes based on block element method

It is difficult to search the dangerous block combination and acquire the safety factor precisely because of the numerous planes of weakness, the complicated block system and the diverse slip modes in rock slopes. Based on block element method, the search of dangerous block combination and the calculation of stability safety factor are conducted. At first, a new method for searching dangerous block combination is proposed, according to the results of block element method through strength reduction calculation. Then, the method for computing safety factors is studied; and the double line intersection method is suggested to calculate the safety factor when the abrupt theory of displacement is adopted. At last, several typical examples are calculated with the proposed methods; and the results are compared with those obtained by using the rigid body limit equilibrium method. The results show that it is more accurate by adopting the block element method, because the force and bending moment equilibrium and the nonuniform distribution of stress on the planes of weakness are considered. The proposed method is expected to be widely used to solve stability problems in complicated rock slopes.