Deflection determination method for BFRP prestressed concrete beams under fatigue loading

Abstract

This paper presents a study on concrete beams prestressed with basalt fiber reinforced polymer (BFRP) tendons subjected to dynamic loading. Usually, structures such as bridge decks, parking garages, offshore structures, are forced to withstand not only static load induced deformations, but also deformations caused by dynamic loading. In this study cyclic creep of concrete phenomena is reviewed. Literature survey on latest models or cyclic creep evaluation techniques such as Balaguru, Bazant and Hubler, Jiang et al., is provided. Based on twelve experimentally tested PC beam results, presented in previous paper (Atutis et al., 2018), a modified cyclic creep of concrete model (CCRM) adopted from Jiang et al. (2017) is presented. Extension to previous experimental tests on basalt fiber reinforcement, performed by the author, is given in the form of equation, evaluating the decrease of elasticity modulus of BFRP reinforcement during cyclic loading. Neveretheless, cyclic load is evaluated thru structural dynamics point of view, using singe-degree-of-freedom system and CCRM. Solution of equation of motion for a four-point loading scheme is being discussed and presented. This study serves validation analysis of proposed model together with proposals for future model developments.