基于强度折减安全系数的边坡岩土侧压力计算方法探讨

对边坡岩土侧压力计算方法进行讨论,指出《建筑边坡工程技术规范》(GB50330–2002)中边坡岩土侧压力计算方法没有与边坡稳定安全系数建立直接联系。传递系数法中的滑坡推力计算安全系数并不是支挡后边坡要达到的稳定安全系数。提出基于强度折减安全系数的岩土侧压力计算新方法,计算时将滑面强度除以一个折减系数,然后再根据力的平衡关系直接计算支挡结构承担的相应荷载。按照此方法,支挡后边坡的稳定安全系数就正好等于侧向岩土压力计算时的强度折减系数。由此得出的岩土侧压力计算安全系数就是指边坡治理后要达到的稳定系数,算例表明该方法的可行性。

DISCUSSION ON CALCULATION METHOD OF SLOPE ROCK-SOIL LATERAL PRESSURE BASED ON FACTOR OF SAFETY WITH STRENGTH REDUCTION

The calculation method of slope rock-soil pressure is discussed. The calculation method of slope lateral pressure in the “Technical code for building slope engineering”(GB50330–2002) is not reasonable because it does not take into account the factor of safety of slope stability. The calculation factor of safety in the imbalance thrust force method is not the true stability factor of safety in reinforced slope. Thus，a new slope thrust calculation method based on the strength reduction is presented. The slope lateral pressure and imbalance thrust force can be carried out through strength reduction. In accordance with this method，the stability factor of safety of reinforced slope is equal to the factor of safety of slope thrust calculation. Analysis and comparison of the imbalance thrust force method and strength reduction method are also discussed. Through a series of case studies，the applicability of the proposed method is clearly exhibited.