STRESS-CONCENTRATIONS OF K-TUBULAR JOINTS SUBJECTED TO BASIC AND COMBINED LOADINGS

A large-scale test rig was designed specially and built to study the b ehaviour of tubular joints subjected to basic and combined loadings. D etailed experimental studies were carried out on a K round-to-round tu bular joint subjected to three basic load cases: i.e. axial loading, i nplane bending and out-of-plane bending, and various combinations of t hese basic load cases. The results were verified by those obtained usi ng the finite element technique. The study shows that the peak hot spo t locations on the K joint subjected to combined loadings shifted from those of the basic load cases. Moreover, the peak hot spot stresses ( HSSs) due to combined loadings were underpredicted by superposition of the basic load cases in some instances. Comparison of the results obt ained by the direct analysis method and some conventional superpositio n procedures reveals that the latter is inadequate in predicting the p eak HSSs of K round-to-round tubular joints.