The effect of corner radius and strain rate on the compressive strength of FRP weakly confined square concrete

doi:10.19936/j.cnki.2096-8000.20210728.010

Abstract

Abstract: Fiber-reinforced polymer (FRP) has been widely used in repair or confinement concrete column. However, most of research has been conducted on the mechanical behavior of FRP strong confined circular concrete. Few studies had focused on the mechanical behavior of FRP weakly confined square cylinder. In order to study the influence of the corner radius ratio and strain rate on the compression mechanical properties of FRP weakly confined square cylinder, an experiment of 20 specimens with different corner radius was carried out under different strain rates. The typical stress-strain curves were drawn based on the test data. The test results show that the compressive strength of FRP weakly confined square cylinder increased with the increase of both corner radius ratio and strain rate. The test results are used to evaluate the existing compressive strength model, and it was found that the existing compressive strength model can be used to predict the compressive strength of FRP weakly confined square concrete under different loading rates.

Key words: corner radius, strain rate, FRP weakly confined concrete, compressive strength, model evaluation, composites

CLC Number:

TB332

MA Chen-yu, JI Yu-peng, LIU Da-wei, LIU Hao-yuan, CAO Yu-gui. The effect of corner radius and strain rate on the compressive strength of FRP weakly confined square concrete[J]. COMPOSITES SCIENCE AND ENGINEERING, 2021, 0(7): 63-67.

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