Abstract: To investigate the mechanical behaviors of multispan corrugated steel plate arch culvert during asymmetric backfill construction, a case study is conducted on a multispan corrugated steel plate arch culvert with reinforcement concrete rib in Meishan, Sichuan province, China, a linear constitutive static finite element model considering the effect of partial load of filling soil and large construction load is established according to the specifications. The maximum equivalent stress and deformation are taken as the control indices, the static response law and structural safety of corrugated steel plate under four typical working conditions are analyzed by comparing with the arch culvert without reinforcement concrete rib. At the same time, considering the structural safety affected by local stress of the arch foot, the bearing capacity of the arch foot angle steel, high strength bolts, and ground bolts is further checked in view of the most unfavorable condition of unilateral backfill to the crown. The results reveal the following: (1) The reinforcement concrete rib can improve the mechanical response of corrugated steel arch culvert, the maximum equivalent stress is reduced by 5 %~8 %, and the maximum deformation is reduced by 17.0 %. (2) When unilateral filling to the crown, the minimum thickness of soil covered on the crown above 0.5 m should be ensured; when a large area of overall backfill is conducted, the minimum thickness of soil covered on the crown is at least 1 m, which is less than the specified value in the specifications.

Key words: multispan corrugated steel plate arch culvert, reinforcement concrete rib, asymmetric backfill, static model, minimum thickness control, structural safety