Distribution of Earth Pressure on Induced Trench Culverts

Abstract

The induced trench construction method has been in practice across North America for the last century, and the analysis and design of such structures are conducted in accordance with Marston’s theory and the indirect design method. Recent North American design standards have adopted the Standard Installations for Direct Design approach for the design of rigid culverts, which does not address induced trench installations. In order to advance the state of practice for induced trench design so as to align with modern design standards, it is necessary to first achieve a fundamental understating of their loading conditions as uncertainties remain with regards to the actual distribution of earth pressures around the circumference of induced trench culverts. In this study, finite-element modeling was employed to evaluate the distribution of earth pressures acting on induced trench culverts; numerical modeling techniques were validated with experimental data and parametric studies were performed to investigate the influence of key design parameters for culverts installed in both single and twin configurations. The results of this study suggest that the distribution of earth pressure acting on induced trench culverts differs significantly from that acting on positive projecting culverts and that the interaction between induced trench twin culverts is not insignificant.