The seismic performance of gravity dam-reservoir-foundation coupled system is investigated utilizing probabilistic approach.In this research,the uncertainties associated with modeling parameters are incorporated in no...The seismic performance of gravity dam-reservoir-foundation coupled system is investigated utilizing probabilistic approach.In this research,the uncertainties associated with modeling parameters are incorporated in nonlinear response history simulations to realistically quantify their effects on the seismic performance of the system.The methodology is applied to Pine Flat gravity dam and the foundation is considered to be inhomogeneous assuming a constant spatial geometry but with various rock material properties.The sources of uncertainty are taken into account in the reliability analysis using Latin Hypercube Sampling procedure.The effects of the deconvolution process,number of samples,and foundation inhomogeneity are investigated.展开更多
The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properti...The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properties o f concrete and thermal loading conditions. Karaj arch dam is selected as case study. The dam is numerically modeled along with its foundation in three-dimensional space;the temperature and thermal stress distribution is investigated during the operating phase. The deterministic thermal finite element analysis o f the dam is combined with the structural reliability methods in order to obtain thermal response predictions, and estimate the probability o f failure in the risk analysis context. The tensile overstressing failure mode is considered for the reliability analysis. The thermal loading includes ambient air and reservoir temperature variations. The effect o f solar radiation is considered by an increase in the ambient temperatures. Three reliability methods are employed: the first-order second-moment method, the first-order reliability method, and the Monte-Carlo simulation with Latin Hypercube sampling. The estimated failure probabilities are discussed and the sensitivity o f random variables is investigated. Although most of the studies in this line o f research are used only for academic purposes, the results of this investigation can be used for both academic and engineering purposes.展开更多
文摘The seismic performance of gravity dam-reservoir-foundation coupled system is investigated utilizing probabilistic approach.In this research,the uncertainties associated with modeling parameters are incorporated in nonlinear response history simulations to realistically quantify their effects on the seismic performance of the system.The methodology is applied to Pine Flat gravity dam and the foundation is considered to be inhomogeneous assuming a constant spatial geometry but with various rock material properties.The sources of uncertainty are taken into account in the reliability analysis using Latin Hypercube Sampling procedure.The effects of the deconvolution process,number of samples,and foundation inhomogeneity are investigated.
文摘The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properties o f concrete and thermal loading conditions. Karaj arch dam is selected as case study. The dam is numerically modeled along with its foundation in three-dimensional space;the temperature and thermal stress distribution is investigated during the operating phase. The deterministic thermal finite element analysis o f the dam is combined with the structural reliability methods in order to obtain thermal response predictions, and estimate the probability o f failure in the risk analysis context. The tensile overstressing failure mode is considered for the reliability analysis. The thermal loading includes ambient air and reservoir temperature variations. The effect o f solar radiation is considered by an increase in the ambient temperatures. Three reliability methods are employed: the first-order second-moment method, the first-order reliability method, and the Monte-Carlo simulation with Latin Hypercube sampling. The estimated failure probabilities are discussed and the sensitivity o f random variables is investigated. Although most of the studies in this line o f research are used only for academic purposes, the results of this investigation can be used for both academic and engineering purposes.
