Strength and behaviour of multi-orientation fillet weld connections

The fact that the difference in deformation ductility can be quite large for welds of different orientations could have a significant impact on the behaviour of connections that combine fillet welds of multiple orientations (MOFW connection). Because of the difference in deformation ductility, there is potential for MOFW connections to fail before the full capacity of all of the welds in the connection reach their full capacity. A test series on welded lapped splice connections containing a transverse weld in combination with either longitudinal or 45° welds was conducted to investigate the effect of weld ductility on MOFW connections. The MOFW connection's capacity is dependent on whether or not the connection will undergo enough deformation in order to mobilize the full capacities of each of the weld segments. The MOFW tests conducted indicate a that a strength lower than the sum of the strengths of the individual weld segments is achieved. A method that incorporates fillet weld load deformation response and addresses the differences in ductilities is presented. This method yields a prediction of any MOFW connection's capacity. A reliability analysis completed for this method indicates that it results in an acceptable safety index.