MPC
Reinforcing Bridge Piers to Withstand Seismic Forces

Posted: Jul 1, 2020

MPC research at the University of Utah shows that reinforced concrete bridge wall piers constructed using older codes can be retrofitted with carbon reinforced polymer rods or vertical CFRP anchors to increase stiffness, load carrying capacity, and hysteretic energy (as occurs in earthquakes) dissipation. The method can also be used to repair damaged bridge wall piers.

In the research, the retrofit methods increased the initial stiffness of the as-built pier by 110%, the lateral load carrying capacity by 73%, and the hysteretic energy dissipation capacity by 67%. The repair method of the as-built pier increased the initial stiffness of the as-built pier by 50%, and load carrying capacity by 73% with similar hysteretic energy dissipation.

The seismic retrofit of existing bridge concrete wall piers is more cost effective and less disruptive than the replacement of such piers. Many U.S. states and elsewhere are in need of such seismic retrofit technologies because deficiencies in wall piers include short reinforcement lap splices, insufficient steel reinforcement ratios in the longitudinal and transverse direction, and inadequate seismic detailing.

Chris P. Pantelides, Ph.D.
University of Utah

Seismic Rehabilitation of Reinforced Concrete Bridge Wall Piers
MPC-19-410