Design of Eccentrically Loaded Welded Joints

In the design of welded structures, shape and length of the weld are defined by the contours of the structure parts and their sizes. The cross section of the fillet weld has the form of the right triangle. The destruction of weld occurs along the weld throat. From the strength calculation we find the throat thickness of the fillet weld and determine the legs of the triangle. When designing a new, eccentrically loaded joint, the stress at the critical point of the weld depends on the position of the centre of mass of the calculated cross-section of the weld. The coordinates of the centre of mass are defined by the shape and size of the cross-section including the unknown throat thickness of the weld. To solve the problem, the leg value is assigned based on the recommendations, experience or intuition, and a test calculation is performed. The calculations are repeated until an acceptable result is obtained. To reduce the labour expense and computing time, it is proposed to perform a design calculation for the weld where throat thickness equals one. The line method makes it possible to transform the analytical dependen cies relative to the leg length or the weld throat thickness and determine them immediately when designing a new joint. The unitary parameters of a single weld are used as components when determining the parameters of a real weld: sectional area, polar moment of inertia, moment of resistance to twisting and other.

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