Title : UTILIZING PRECAST GIRDERS TO PROMOTE ACCELERATED BRIDGE CONSTRUCTION IN HIGH SEISMIC REGIONS
Authors : Sri Sritharan, Justin Vander Werff, Zhao Cheng, Robert Peggar
Publication : 8 - 10, October 2015
Volume : 2
Pages :
Price : 250
Abstract : The use of precast girders has helped to promote Accelerated Bridge Construction (ABC) methods in the United States. However, this practice has not been extended in seismic regions due to the lack of reliable seismic connections between precast girders and cap beams. This paper characterizes the basic challenges associated with current design practice and introduces several options to establish reliable seismic connections between precast girders and cap beams. Two mechanisms are used to establish the positive moment continuity in these connections, namely shear friction and direct tension transfer. Deck reinforcement is primarily used to ensure tension continuity for the negative moments. Using a large-scale experimental study, six different details suitable for connecting precast concrete girders to concrete cap beams have been evaluated using simulated seismic loading. All connections exhibited excellent seismic performance, remaining elastic up to load levels well in excess of what would be required to develop a plastic hinge at the top of the column, including consideration to the effects of vertical accelerations. This paper presents a summary of experimental evaluations of all the connections and their comparative seismic performance with respect to the performance of an as-built connection.