TENSILE BEHAVIOR AND STRENGTH OF STEEL PLATE BONDED WITH UV-CURABLE GLASS FIBER REINFORCED POLYESTER RESIN SHEET ON BOTH SIDES

Abstract

Steel structures in social infrastructures often undergo corrosion and the thickness of these steel
plates decreases. Then, the strength of steel structures decreases according to the residual plate thickness.
Applications of a steel plate attaching method and a fiber reinforced polymer/plastic (FRP) bonding method
are effective for repair and strengthening for these steel structures. In this study, UV-curable glass fiber
reinforced polyester resin (UV-GFRPR) sheet was focused instead of FRPs. The aims of this study are to
confirm repair and strengthening effects of the UV-GFRPR sheet bonded on both sides of steel plate. The UVGFRPR sheet consists of a polyester resin and chopped glass fibers and is hardened by radiation of UV source
for a certain time. The tensile behavior and strength of steel plate bonded with UV-GFRPR sheets were assessed
under axial tensile load. After that, the tensile behavior and strength of specimens were numerically estimated
from each stress-strain curve of UV-GFRPR and steel modeled by using Menegotto-Pinto model. Furthermore,
nonlinear finite element analysis (FEA) taking into account of the properties of bond layers was carried out to
compare the numerical results. From the test results, the yield and ultimate strengths of specimens increased
linearly according to the number of laminated layers of UV-GFRPR. Both results of the numerical calculation
and the FEA agreed well with the test results. It is concluded that the numerical calculation without the
contribution of bond layers can estimate the tensile behavior and strength of steel plate bonded with UVGFRPR on both sides