This study investigated the influence of probabilistic variability in stiffness and nonlinearity of soil on response of nuclear power plant (NPP) structure subjected to seismic loads considering the soil-structure interaction (SSI). Both deterministic and probabilistic methods have been employed to evaluate the dynamic responses of the structure. For the deterministic method, SRPmin method given in USNRC SRP 3.7.2(2013) (envelope of responses using three shear modulus profiles of lower bound(GLB), best estimate(GBE) and upper bound(GUB)) and SRPmax method (envelope of responses by more than three ground profiles within range of GLB≤G≤GUB) have been considered. The probabilistic method uses the Latin Hypercube Sampling (LHS) that can capture probabilistic feature of soil stiffness defined by the median and the standard deviation. These analysis results indicated that 1) number of samples shall be larger than 60 to apply the probabilistic approach in SSI analysis and 2) in-structure response spectra using equivalent linear soil profiles considering the nonlinear behavior of soil medium can be larger than those based on low-strain soil profiles.

The purpose of this study is to investigate the variation of tension of existing tendon by additional tendon installation. As a result of the analysis, it was found that the tension value was decreased overall compared with before tenden reinforcement. The cause of the reduction of tension is presumably due to the effect of reinforcement.

In this study, measurement temperature in the bridges was compared with temperature proposed by Korean design code. In addition, the structural analysis was performed in order to comparing the stress by measured thermal load and the stress by design thermal load. As a result, the stress that applied measurement temperature was evaluated larger than the stress that applied temperature proposed by Korean design code.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum effective stresses of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that the inspection installation is possible to the inflection point of the girder.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum von mises stresses(SE) of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that the inspection installation is possible to the inflection point of the girder because buckling phenomenon doesn't occur according to the loading.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum von mises stresses(SE) of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that it is reasonable the hole is installed near the inflection point of the girder from a structural safety point of view though additional cost for the inspection walkway