Abstract：The method for multiple surface deep anti-sliding stability in current design code for concrete gravity dams，has a serious mistake to sum up the scalar ΔQi in different directions which is the resistance resultant force on both sides of each slider. In view of the shortcomings of the standard method，this paper proposes a modified method with ∑ΔQ = 0 to really satisfy the balance of internal forces. At the same time，the modified method adds an unknown variable φm，which solves the problem of redundancy assumption that each φi for ΔQi is known in the standard method. For the revised formulas mentioned above，two solving methods，i. e. internal force balance method and η equality method，are proposed in this paper. The accuracy and practicability of the modified method are proved by test questions and engineering example. Sensitivity calculation of different variable φm is carried out. It is found that better calculation accuracy can be obtained by choosing slider m which has less influence. This method corrects the errors in the code and can obtain accurate calculation results，which is beneficial to the popularization and application of the multi-slip surface calculation method for dam foundation.
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PENG Wenming. Discussion on calculation method of multi-slip surface anti-sliding stability with resistance resultant force on both sides of slider as variable. , 2019, 38(S2): 3833-3840.
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2019, Vol. 38 
