Design of precast piers using steel-embedded composite sections

Abstract

In the design of bridge piers in congested area it is necessary to reduce the dimensions of columns considering design criteria and to minimize the construction period. In the civil engineering community prefabricated structures and systems have received increasing attention as a way to increase construction speed to enhance work zone safety and to minimize the environmental impact. Among various prefabricated bridge piers a circular precast composite columns with composite section was proposed and extensive experimental studies were performed. The embedded steel member can increase ultimate strength and seismic performance and also provides a connection to other parts without prestress. Especially in seismic area the ductility requirement is the most important factor in the design of piers. In this paper precast steel-embedded composite columns with core steel elements embedded in concrete were dealt with Connection details without prestressing between footing and pier element were also suggested for the fast erection. In order to investigate the seismic performance of the composite columns several tests on concrete encased composite columns which are prefabricated were performed. Quasi-static tests were carried out and their performance was evaluated and compared each other. Through the tests it was evaluated the ductility of SRC composite specimens and comparisons with normal CIP composite columns were done. It has become clear from the test results that encased steel elements makes the deformation capacity of the columns to be large. For relatively small size columns precast SRC columns can be excellent alternatives for bridge substructures without any prestressing. Based on the research design considerations and examples were suggested and various alternatives for precast piers with prestressing were discussed.