The seismic behavior of the bedrock foundation during earthquakes concerns the stability and safety of nuclear power plants. Discontinuities like joints and faults existing in rock masses affect significantly the dyna...The seismic behavior of the bedrock foundation during earthquakes concerns the stability and safety of nuclear power plants. Discontinuities like joints and faults existing in rock masses affect significantly the dynamic behavior of bedrock. The dynamic FEM （finite element method） has been commonly utilized to analyze the seismic responses of bedrock, however, it cannot well represent the large deformation behavior of discontinuities. The DEM （distinct element method） has a better capability of simulating the sliding and separation of discontinuities existing in the bedrock, which influence the propagation of seismic waves. In this study, the dynamic FEM and DEM simulations were carried out to investigate the seismic behavior of the bedrock foundation under a nuclear power plant, and the differences between those two methods were illuminated. Numerical simulation results indicate that the FEM underestimates the attenuation effect of faults on the propagation of seismic waves. With the capability of simulating large deformation behavior of discontinuities, the DEM can be regarded as a better method for studying the seismic responses of bedrock foundation which contains discontinuities.展开更多
This paper expatiated the field test of large diameter cast in place piles embedded in soft rock, including static loading test, high or low strain dynamic test, measurement of stresses and strains of pile body, and p...This paper expatiated the field test of large diameter cast in place piles embedded in soft rock, including static loading test, high or low strain dynamic test, measurement of stresses and strains of pile body, and pressure measurements between pile tip and soft rock. The relative in situ test problems are discussed. Based on the limit equilibrium theory and the load transfer equation, a synthesis method of analyzing the ultimate carrying capacity of single large diameter pile is put forward. The research results show that the key to determining the ultimate carrying capacity of single pile with a large diameter is the analysis of the intensity of soft rock.展开更多
文摘The seismic behavior of the bedrock foundation during earthquakes concerns the stability and safety of nuclear power plants. Discontinuities like joints and faults existing in rock masses affect significantly the dynamic behavior of bedrock. The dynamic FEM （finite element method） has been commonly utilized to analyze the seismic responses of bedrock, however, it cannot well represent the large deformation behavior of discontinuities. The DEM （distinct element method） has a better capability of simulating the sliding and separation of discontinuities existing in the bedrock, which influence the propagation of seismic waves. In this study, the dynamic FEM and DEM simulations were carried out to investigate the seismic behavior of the bedrock foundation under a nuclear power plant, and the differences between those two methods were illuminated. Numerical simulation results indicate that the FEM underestimates the attenuation effect of faults on the propagation of seismic waves. With the capability of simulating large deformation behavior of discontinuities, the DEM can be regarded as a better method for studying the seismic responses of bedrock foundation which contains discontinuities.
文摘This paper expatiated the field test of large diameter cast in place piles embedded in soft rock, including static loading test, high or low strain dynamic test, measurement of stresses and strains of pile body, and pressure measurements between pile tip and soft rock. The relative in situ test problems are discussed. Based on the limit equilibrium theory and the load transfer equation, a synthesis method of analyzing the ultimate carrying capacity of single large diameter pile is put forward. The research results show that the key to determining the ultimate carrying capacity of single pile with a large diameter is the analysis of the intensity of soft rock.
