Experimental study on the web crippling behaviour of pultruded GFRP channel sections using DIC

School of Transportation Science and Engineering, Beihang University, 37 Xueyuan Road, Beijing 100191, China

Corresponding author: wuchao@buaa.edu.cn
^* Corresponding author: wuchao@buaa.edu.cn

Abstract

The use of pultruded glass fibre reinforced polymer has gained wide acceptance in civil engineering due to their excellent physical and mechanical characteristics, like low weight, high strength and durability in harsh environment. However, duo to the pultrusion process, pultruded GFRP sections are orthotropic and face a critical issuse of web crippling. This paper presents an experimental study on the web crippling behavior of pultruded GFRP channel sections under transverse bearing load. A total of twenty specimens were tested under two loading conditions, namely end-two-flanges (ETF) and interior-two-flanges (ITF). Five different bearing plates with length ranging from 20 mm to 200 mm were chosen to apply the transverse concentrated loading. It is observed taht all specimens initially cracked at the web-falnge junction. The experimental result also confirmed that both the web crippling capacities and stiffness increased with the increase of the bearing length. And the web crippling capacities are improved when the bearing plates are moved from the end to the middle of the specimen. The strain distributions at the web-flange junction obtained by DIC indicated that both the materials underneath the bearing plates and that near the bearing plates engaged in carrying the transverse bearing load.