Flexible culverts in sloping terrain: Numerical simulation of soil loading effects

• The performance of soil–steel composite bridges is investigated when constructed in sloping terrain.
• A number of 2D finite element models were created to simulate three case studies.
• The effect of structure presence in the soil was investigated in terms of soil stability.
• The results enable to realize the susceptibility of such structures to low heights of soil cover.
• The safety factor of soil stability is found to decrease when introducing flexible culverts in the soil.

This paper investigates the performance of flexible culverts – often referred to as soil–steel composite bridges (SSCB) – when constructed in sloping topography. A number of 2D finite element models were created to simulate three case studies compromising two pipe arches and one high profile arch. The models were generated to investigate the effect of different surface slopes for different depths of soil cover. The aim was to understand and perceive the change of sectional forces in the structure with respect to slope increase under different soil covers. In addition, the effect of structure presence in the soil was also investigated in terms of soil stability. The results enable to realize the susceptibility of such structures to low heights of soil cover when built in sloping environment, which is seen in the incremental change in displacements and sectional forces, specially the bending moments. It is also found that the geometrical aspects of the profile shapes have more pronounced effect on their performance when introducing steeper slopes. The safety factor of soil stability is found to decrease when introducing such structures in the soil.