Allowable debonding strain limitation ofexternally CFRP-strenghtened RC beam

doi:10.16265/j.cnki.issn1003-3033.2018.07.012

Abstract

Abstract: In order to further clarify the failure modes of RC flexural members strengthened with CFRP,and determine the accuracy of the formula for determining CFRP allowable debonding strain proposed by relevant codes,experimental tests were carried out to investigate the failure mode and tensile strain in CFRP laminates at initial debonding of CFRP-strenghtened RC beams which were simply supported and loaded under two points symmetrical loading.The results show that the main failure mode of the strenghtened beams is CFRP laminates debodning; the allowable debonding strains are 0.28-5.12 times of the tested tensile strains at initial debonding with a coefficient of variation more than 46%,and most of the code models highly overestimate the allowable debonding strain; the debonding of CFRP laminates of flexural strenghtened RC beam is related not only to the concrete strength,the amount of FRP laminates,and the modulus of elasticity,but also to the factors such as shear-span ratio,stirrup reinforcement ratio and longitudinal reinforcement ratio.

Key words: reinforced concrete (RC), carbon fiber reinforced polymer (CFRP), externally bonding, debonding failure, allowable debonding strain

CLC Number:

X948

XU Junyan, ZHENG Binbin, LI Guibing. Allowable debonding strain limitation ofexternally CFRP-strenghtened RC beam[J]. China Safety Science Journal, 2018, 28(7): 70-75.

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