Numerical Investigation of Dynamic Load Amplification in Buried Culverts

Abstract

Most traditional research on buried culverts has looked at live load distribution through soil onto buried culverts without due attention to the dynamic amplification of moving loads. Few studies that considered the dynamic amplification of buried culverts modeled the system assuming plane strain conditions. Under such conditions, finite area loads such as the wheel loads of vehicles must instead be modeled as strip loads that act over the entire culvert width. In this study, the load-soil-culvert system is also treated as a three-dimensional problem. A dynamic amplification factor (DAF) is determined from two-dimensional (plane strain) and three-dimensional finite element analyses and is compared with DAFs calculated following the American Association of State Highway and Transportation Officials (AASHTO) procedures and field collected data. The two- and three-dimensional finite element analyses resulted in average DAFs of 1.10 and 1.03, respectively. Average DAFs from field and the AASHTO procedures were calculated to be 0.97 and 1.30, respectively. Overall, the AASHTO DAFs are the highest and the field DAFs are the lowest. The two-dimensional finite element results gave DAF values that are higher than the ones from three-dimensional analyses and field evaluated values. The DAF calculated from three-dimensional finite element analyses is the closest to the field measured DAFs.