Fatigue behavior of CFRP repaired non-load carrying cruciform welded joints

Abstract

In recent years, large amount of research has been conducted on carbon fibre reinforced polymer (CFRP) strengthening of steel members. There is very limited work on CFRP strengthening of welded connections. This paper reports an experimental study on the use of CFRP sheets to rehabilitate non-load carrying cruciform welded joints subjected to fatigue loading. Failure modes and corresponding fatigue lives were rec-orded during tests. Thereafter, series of numerical analyses were performed to understand the effects of weld toe radius, layer of CFRP sheets and Young's modulus of reinforced materials on local stress concentration at weld toe. It was found that fatigue life of such welded connections can be enhanced by CFRP sheets. A para-metric study was also carried out. It was found that the weld toe radius and the number of CFRP layers are the key parameters influencing the stress concentration factors of such joint. © 2011 Tsinghua University Press, Beijing and Springer-Verlag Berlin Heidelberg.