Elasto-plastic 3D FE analysis of the seismic behavior in culvert longitudinal direction of three-hinge type of precast arch culverts

Abstract

The Great East Japan earthquake (11 March 2011) caused loss of serviceability on many three-hinge type of precast arch culverts, which indicated the importance of clarification of its damage mechanism. However, there is no effective seismic evaluation method available in the current design criteria of the precast arch culverts for the observed damages correlated with the inertial force to the longitudinal direction. On the other hand, our research group has conducted the series of dynamic centrifuge tests on the precast arch culverts to observe the seismic behavior in culvert longitudinal direction. As aresult, the seismic behavior in the longitudinal direction of the precast arch culverts is controlled by their longitudinal, structural connectivity and confining stress of the culverts from the embankment. In short, in a numerical analysis, the longitudinal seismic behavior of the precast arch culverts should be governed by these effects due to longitudinal, structural connection and overburden of culverts. Therefore, in the present study, 3D elasto-plastic finite element analyses for three-hinge type of precast arch culvert were conducted to develop a new evaluation method for the longitudinal, seismic performance of the precast arch culverts. In these analyses, the structural connection is modeled by nonlinear spring element and the slip and separation between the culvert and the soil is modeled by joint element. From the analysis results, the patterns of the deformation of the culverts and the embankment and axial force behavior of the structural connections due to the various embankment shape can be evaluated.