Constructional behavior of multi-span corrugated steel arch culverts stiffened by concrete rings

Abstract

Corrugated steel arch culverts have gained widespread use due to their excellent mechanical performance. However, as their span increases, they become more susceptible to deformation during backfilling. Reinforcing the cross-section with concrete rings is a common mitigation measure. Despite this, current research on the mechanical behavior of multi-span, full-scale structures during backfilling remains notably sparse. This study uses in-situ tests and numerical simulation methods to compare the mechanical behaviors of structures with and without concrete rings. It also analyzes the variations between different backfill options. This research investigates the structural behavior during construction and assesses the mechanical contribution of concrete rings. The findings revealed that the presence or absence of concrete rings minimally affects the deformation of arch culverts in field tests using foam concrete as backfill. However, these rings considerably reduce stress in the corrugated steel plates, particularly at the crest of the arch foot. Incorporating a concrete ring in finite element simulations markedly diminishes stress and deformation in the steel corrugated plate during asymmetric backfilling with sand gravel. Although the concrete ring increases the overall force, it effectively reduces the force within the corrugated steel plate. The concrete ring is most beneficial at the arch foot, absorbing 50.3% of the internal forces in the section. Compared to asymmetric backfilling with sand gravel, foam concrete backfill results in a more uniform stress distribution on the arch culvert. This leads to a significant 70.11% reduction in stress on the steel corrugated plate and a 61.02% decrease in deformation.