Experimental Research on Calculation Parameters of GFRP Bars Tensile Strength

Abstract

A tensile test on the 18mm diameter (φ18) and 25mm (φ25) GFRP bars was conducted to observe the tensile apparent characteristics and failure strength. The value calculated by failure strength fomula and the experimental value were ,contrasted to study the parameters and value of the strength calculating formula,, and drawn the conclusions as follows: The φ18 and φ25 GFRP bars' failure strength is effected by fiber materials, enhance materials itself and interface performance. The φ18 bars’ failure strength is about 10% higher than φ25 bars’. The deviation between the calculated value and the actual value is more than 30%. k is the correction parameter in theoretical formula, kφ18=0.76, kφ25 = 0.68 is appropriate. Based on statistical intensity distribution model of GFRP bars’ failure strength, reference stresses value of the φ18 and φ25 GFRP bars are different and the diameters of GFRP bars increases to weaken the strength of the composite material. The reducing rate of the reference stresses is significantly affected by the diameters. The diameters effect is greater than the fiber content effect.