TWI Industrial Member Report Summary 422/1990
By S W K Chan
Background
A static load test has been carried out on a large-scale plate specimen manufactured to simulate a fillet welded double-covered splice between steel plates. The objective was to study the elastic-plastic strain history throughout the weld zone up to ultimate failure in more detail than had been achieved by
other researchers.
This work represents an important step in the search for an understanding of the fundamental material and geometrical factors which determine the ductility of fillet welded joints in statically loaded structures. The prediction of fillet weld ductility is vital to the reliable use of fillet welds in complex structural joints of variable stiffness. Greater confidence in the use of fillet welds by designers would result in substantial savings in many steel structures where costly butt welds are frequently specified unnecessarily.
A weld leg length of 100mm was chosen so that the 99 strain gauges could be accommodated in the weld region. The post-yield strains were converted to stresses using a purpose-made computer program.
The work has been done in collaboration with the Civil Engineering Department of Leeds University, who are developing elastic-plastic finite element computer models for fillet welded joints.