Numerical Modeling of Soil and Surface Foundation Pressure Effects on Buried Box Culvert Behavior

Box culverts can be subjected to considerable induced earth pressure from overlaying structures and foundations. Therefore, the effect of surface foundations on soil pressures around box culverts needs to be properly investigated and incorporated into the analysis and design of culverts. In this study, the effect of a surface foundation on the response of box culverts was investigated experimentally and numerically. A series of centrifuge tests were performed to evaluate the additional soil pressures around box culverts installed in sand due to adjacent surface foundations. The experimental results were used to calibrate and verify a two-dimensional (2D) numerical model developed using computer software. This model was then used for a parametric study to investigate the effect of the relative foundation location on various aspects of the culvert response. The soil pressures, culvert bending moments, and soil-culvert interaction factors were all considered for different soil depths and surface foundation locations. The results from this analysis were used to establish charts that can aid in assessing the effect of surface foundations on box culvert behavior.