Heavy rainfall and subsequent flooding on the Turkey River in northeastern Iowa caused the derailment of a passing train at Bridge K212 at M.P. 71.7 on the the Iowa, Chicago & Eastern (IC & E) Railroad. The washout caused extensive damage to the bridge, including a vertically shifted and cracked south abutment at the track centerline, a fallen concrete backwall and a 66-foot-long single track span was sent into the river. Benesch was enlisted to assist with the design and construction of a temporary replacement bridge to restore service as quickly as possible.
The following morning, on-site meetings began with the railroad and contractors to decide temporary bridge configuration, needed materials and preferred construction methods. Benesch designed innovative framing plans and steel details for the rolled beam spans and verified the design capacity. Benesch also provided an on-site survey crew to assist the railroad and the contractors with setting line and grade, establishing pile locations and the pile cut-off elevations. Extensive coordination with contractors and fabricators was required to help expedite the construction and fabrication process.
The temporary bridge was completed and ready for operational use in approximately two weeks. Immediately after the temporary bridge was completed and carrying rail traffic, Benesch continued on to design the permanent spans and substructure.