Experimental research on bond strength of deformed GFRP rebars with different surface configurations

HAO Qing-duo^1,2, WANG Yan-lei³, OU Jin-ping^2,3

1.Harbin Quality Supervising Central Station of Construction Engineering,Harbin 150076,China;2.School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;3.School of Civil and Hydraulic Engineering,Dalian University of Technology,Dalian 116024,China



Abstract:

Based on the Canadian Standards Association(CSA) criterion,experiments on 30 pull-out specimens were conducted to study the bond strength of deformed GFRP rebars with 8 different surface configurations.Each rebar was embedded in a 150 mm concrete cube,and the test embedded length was four times of the rebar diameter.Relationship between the mode of failure,the average bond strength and the average bond strength-slip for each rebar was analyzed.Results show that the failure mode of all specimens is the shearing off or desquamation of ribs,no splitting cracks appear on the cube specimens.The bond stress of deformed GFRP rebars mainly depends on the mechanical interaction between the ribs of the bar and the surrounding concrete,and the bond strength of deformed GFRP rebars is improved obviously.The optimal rib spacing is less than 2.5 times of the rebar diameter,and the rib height is more than 3% of the rebar diameter.

Key words:  deformed GFRP rebars  concrete  bond strength  pull-out test  rib spacing  rib height  optimal surface configuration

DOI：10.11916/j.issn.1005-9113.2009.04.006

Clc Number:TU377

Fund: