Abstract：The design method is crucial to meet the requirement of safety and economy of the support system of foundation pit. On the basis of the soil strength design method according to plastic deformation and the engineering experience，the deformation mechanism of the foundation pit system was modified，and an improved MSD method was proposed. This method is suitable for the analysis of excavating process of deep foundation pit with internal bracing. In the energy conservation equation，the influence of the compressive deformation energy in the internal support，the bending deformation energy in the retaining wall above the excavation surface and the buried depth of the excavation surface of the foundation pit are considered. The curve form of the variable wave peak is proposed to be cosine function. The improved method has been successfully applied in engineering practice. In comparing with the original MSD method and the vertical elastic foundation beam method，the improved MSD method agreed better with the measured values.
刘美麟，房 倩，张顶立，侯艳娟. 基于改进MSD法的基坑开挖动态变形预测[J]. 岩石力学与工程学报, 2018, 37(7): 1700-1707.
LIU Meilin，FANG Qian，ZHANG Dingli，HOU Yanjuan. Prediction of transient deformation due to excavation based on improved MSD method. , 2018, 37(7): 1700-1707.
VARDANEGA P J，BOLTON M D. Strength mobilization in clays and silts[J]. Canadian Geotechnical Journal，2011，48(10)：1 485-1 503.
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2018, Vol. 37 
