Experimental investigation on seismic behavior of Ultra-high performance concrete columns reinforced with GFRP bars

Abstract

Owing to its outstanding mechanical and structural properties, ultra-high performance concrete (UHPC) has triggered rapidly increasing interest among both construction industry and research community. Numerous studies have been conducted at the structural level to explore the benefits brought by UHPC. Nonetheless, currently there is hardly any published studies on the seismic performance of UHPC columns reinforced with glass fiber reinforced polymer (GFRP) bars. This paper presents an experimental campaign carried out on seven UHPC columns subjected to simulated seismic loading. The variables include the type of reinforcement, the type of concrete, the cross-sectional area, and the transverse reinforcement. The seismic performance of specimens was thoroughly assessed in terms of cracking patterns, failure modes, hysteretic responses and strain profiles. The results show that specimens cast with UHPC have superior seismic performance, especially in terms of lateral load capacity and energy dissipation capacity. Moreover, it is found that the adoption of GFRP bars effectively prevents the formation of cracks while having limited adverse impacts on the seismic performance of UHPC columns. Therefore, the hybrid of UHPC and GFRP bars provides a new design opportunity for columns in a harsh environment.