Studies on fatigue life of typical welded and bolted steel structural connections

Abstract

This paper presents the results of fatigue tests conducted on typical welded and bolted connections made of IS 2062: 2011 steel and conforming to selected Constructional Details categorised in IS 800: 2007. The connection types include: Longitudinal and transverse butt welded connections, fillet welded cruciform connections with load-carrying and non-load-carrying welds, and bolted (double cover butt type) connections. The tests were carried out at various values of maximum stress which were decided as a percentage of the yield strength of the base material. The S-N data obtained were compared with the characteristic S-N curves recommended in IS 800: 2007. In the case of transverse butt welded joints, all specimens which were tested at a maximum stress value equal to 65 % of the yield strength of the material and above, and one out of the two specimens tested at a maximum stress value equal to 60 % of the yield strength of the material failed to satisfy the codal provisions. Two out of the three cruciform joints with loadcarrying welds tested at a maximum stress value equal to 80 % of the yield strength of the material failed to satisfy the codal provisions. Bolted specimens which were tested at a maximum stress value equal to 60 % of the yield strength of the material and above failed to satisfy the codal provisions.