Seismic retrofit of the Poplar Street Bridge

In work for the Missouri Department of Transportation (MoDOT) Sverdrup Civil, Inc. performed a seismic evaluation and developed a seismic retrofit strategy for the Poplar Street Bridge over the Mississippi River at St. Louis. The 660 meter (2,165 foot) structure consists of two parallel five span continuous roadways with orthotropic steel plate deck and variable depth steel box girders. The seismic evaluation considered three levels of design earthquakes and identified deficiencies in the bearings, reinforcement splices in the columns and piers, and one foundation. The retrofit strategy includes adding force transmitters or dampers to the existing expansion bearing piers, adding transverse shear blocks to the beam seats, jacketing the column splices, adding rock anchors to one foundation, and adding supplemental reinforcement to address lap splice deficiencies at the base of the piers.