THEORETICAL ANALYSIS OF STEEL TUBE WITH CROSS-SECTIONAL LOSS REPAIRED BY CFRP BONDING

Abstract

Bonding carbon fiber reinforced plastic (CFRP) is one of the repair methods for corroded steel tube members. In this research, loading tests were conducted for the steel tube with cross-sectional loss repaired by CFRP bonding. As a result, it was confirmed that the effectiveness of the repair method decreased compared to the calculated values of the composite theory for the sectional forces shared between the defective steel tube and the CFRP. This is caused due to sectional force transfer by the adhesive. For CFRP bonding repair, a shear-lag theory has been proposed to evaluate the sectional force transfer through the adhesive. However, there is no theoretical solution for steel tube with cross-sectional loss repaired by CFRP bonding. Therefore, in this study, the shear-lag theory was applied to a steel tube with cross-sectional loss repaired by CFRP bonding to derive the shared sectional forces. The derived shared sectional forces were in good agreement with the results of axisymmetric analyses based on finite element analysis and loading tests.