The performance of buried pipes is affected by seismic wave propagation and its incidence due to out-of phase induction motion. In this study, three dimensional finite element models have been employed to evaluate the effect of bend angle and soil mechanical properties on seismic response of buried pipe in bent area. In these models, beam and nonlinear spring elements were used to simulate pipe and soil-pipe interaction, respectively. Furthermore, a suitable boundary condition has been used to simulate far field effect more closely. The travelling of seismic waves was assumed to be parallel to a pipe leg, causing time lag in vibration of different points of model. The influences of geometrical parameters such as diameter-to-thickness ratio and embedment ratio on elbow strains were also considered. Results indicated that a direct relationship exists between soil stiffness and axial strains due to smaller slippage. Diameter-to-thickness is a definitive ratio for axial strain of bend while effect of the embedment ratio is small.
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