Effect of Hinge-Type Connections on the Lateral Cyclic Behavior of a Prestressed High-Strength Concrete Pile

Abstract

This paper presents the cyclic behavior of a prestressed high strength concrete (PHC) pile with hinge-type pile head connections designed for reducing the bending moment due to lateral loads. The PHC pile is a hollow cylindrical prestressed pile made by centrifugal compaction and is being increasingly used in the foundation of civil structures because of its good seismic performance and cost effectiveness. This study investigated the seismic performance of full-scale PHC piles with four head types. The pile specimens consist of a reference specimen with no pile cap, a hinge specimen with a pile cap on the head, a hinge specimen with a pile cap and reinforcing steel, and a hinge specimen with prestressing steel. The cyclic response of the four PHC pile specimens was obtained by quasi-static tests conducted with displacement-controlled lateral cyclic loadings. According to the test results, the PHC pile with a pile cap had the best lateral displacement capacity among the specimens. The other hinge specimens also showed good cyclic performance with only minor damages due to the reduced bending moment around the pile head, whereas the reference specimen with no pile cap exhibited severe damage. It was observed from hysteresis curves that the PHC pile with a pile cap had better bearing and energy dissipation capacities compared to the regular reinforced concrete pile. Design features of the PHC piles, experimental configuration, and the test results will be presented. The proposed head connections can be used to diminish the flexural damage of PHC piles due to ground motions.