A NEW SEISMIC RESISTANT DESIGN METHOD OF BURIED CULVERTS CONSIDERING INTERACTION BETWEEN SOIL AND STRUCTURE

1/30-scaled static centrifuge model tests and an elastic FE analysis were conducted to investigate the seismic behavior of buried RC-pipe, FRPM-pipe and box-culvert. In the tests, distributions of normal and tangential earth pressures acting on the surfaces of the three types of model culverts, as well as those of bending strains produced in their walls were precisely measured during cyclic simple shear deformation of the model ground. Test results showed that the tangential earth pressures acting on the culverts were almost null in any case. Numerical results of the FE analysis in which slip and separation at the culvert-ground interface were allowed showed good agreement with the test results. However, the prediction from the current seismic design standard for buried sewer culverts using seismic deformation method based on spring model contradicted the test and numerical results in both earth pressure and bending moment distributions. An analysis using continuum models based on elastic theory clarified that the seismic deformation method has theoretical defects in predicting the earth pressure. Therefore, the FE method used in this study was proposed as a new seismic resistant design method of buried culverts.