| Deep foundation pit-retaining is one of key problems in rock and soil engineering. Structure design and excavation by steps of deep foundation pit-retaining are studied theoretically and numerically in this paper and of importation in design and construction of soil nailing retaining structure of deep foundation pit. Main results are obtained as follows:Based on analysis of current deep foundation pit-retaining, weakness problem of pit-retaining theory, shear stress of soil nailing and stability calculation are proposed in soil nailing design.Initial stresses and displacements before excavation are investigated by finite element method and new idea is proposed for formation and calculation of excavation release load.Application of Morh-Coulomb yielding condition in PLAXIS finite element software is discussed and conditions of five basic parameters including Young's modulus, Poisson ratio, cohesion, friction angle and dilatancy angle are determined.Excavation by steps of soil nail retaining structure of deep foundation pit in Changsha city is simulated by PLAXIS finite element software. Numerical results are in good agreement with tested results, which verifying the correction of calculation, and of signification in design and construction of soil nailing retaining structure of deep foundation pit. |
PDF Full Text Request