The hyperbolic function proposed by Abbo- Sloan was employed not only to approach the Mohr- Coulomb criterion but also to express the plastic potential function. A better approximation to the Mohr-Coulomb yield and po...The hyperbolic function proposed by Abbo- Sloan was employed not only to approach the Mohr- Coulomb criterion but also to express the plastic potential function. A better approximation to the Mohr-Coulomb yield and potential surfaces was achieved by increasing the transition angle and proven to be highly efficient in numerical convergence. When a Gaussian integral point goes into plastic state, two cases on yield stress adjustments were introduced. They may avoid solving the second derivative of the plastic potential function and the inverse matrix compared with the existing subroutine. Based on the above approaches, a fully implicit backward Euler integral regression algorithm was adopted. The two- and three-di- mensional user subroutines which can consider the asso- ciated or non-associated flow rule were developed on the platform of the finite element program--ABAQUS. To verify the reliability of these two subroutines, firstly, the numerical simulations of the indoor conventional triaxial compression and uniaxial tensile tests were performed, and their results were compared with those of the embedded Mohr-Coulomb model and the analytical approach. Then the main influential factors including the associated or non- associated flow rule, the judgment criteria of slope failure, and the tensile strength of soil were analyzed, and the application of the two-dimensional subroutine in the sta- bility analysis of a typical soil slope was discussed in detail through comparisons with the embedded model and the limit analysis method, which shows that this subroutine is more applicable and reliable than the latter two.展开更多
Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion.Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the conc...Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion.Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile(EBP)could be useful in finding the most suitable measure to address the erosion problem.Field investigation data of 11 beaches along the eastern tombolo were supplied for this study,and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP.All of the observed beach profiles could be described by a single function,but a single EBP was inadequate to represent all of the beach profiles observed.The variation found could be explained in terms of longshore variation of bathymetry,sediment size,and wave parameters.Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.展开更多
文摘The hyperbolic function proposed by Abbo- Sloan was employed not only to approach the Mohr- Coulomb criterion but also to express the plastic potential function. A better approximation to the Mohr-Coulomb yield and potential surfaces was achieved by increasing the transition angle and proven to be highly efficient in numerical convergence. When a Gaussian integral point goes into plastic state, two cases on yield stress adjustments were introduced. They may avoid solving the second derivative of the plastic potential function and the inverse matrix compared with the existing subroutine. Based on the above approaches, a fully implicit backward Euler integral regression algorithm was adopted. The two- and three-di- mensional user subroutines which can consider the asso- ciated or non-associated flow rule were developed on the platform of the finite element program--ABAQUS. To verify the reliability of these two subroutines, firstly, the numerical simulations of the indoor conventional triaxial compression and uniaxial tensile tests were performed, and their results were compared with those of the embedded Mohr-Coulomb model and the analytical approach. Then the main influential factors including the associated or non- associated flow rule, the judgment criteria of slope failure, and the tensile strength of soil were analyzed, and the application of the two-dimensional subroutine in the sta- bility analysis of a typical soil slope was discussed in detail through comparisons with the embedded model and the limit analysis method, which shows that this subroutine is more applicable and reliable than the latter two.
基金financially supported by the 911 Project of Vietnam International Education Development,Ministry of Education and Training,Vietnam
文摘Beaches along the eastern branch of the Giens double tombolo are subject to coastal erosion.Prediction of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile(EBP)could be useful in finding the most suitable measure to address the erosion problem.Field investigation data of 11 beaches along the eastern tombolo were supplied for this study,and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant EBP.All of the observed beach profiles could be described by a single function,but a single EBP was inadequate to represent all of the beach profiles observed.The variation found could be explained in terms of longshore variation of bathymetry,sediment size,and wave parameters.Analysis of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.
