Strength Analysis of Large-Scale Multiplanar Tubular Joints with Inner-Plate Reinforcement

For large scale multiplanar tubular joints used in practical engineering, the brace/chord intersection is a critical position as failure usually occurs here due to the weak bearing capacity of the chord in radius direction compared to the strength of the braces in axial direction. To improve the ultimate strength, different reinforcements can be used to strengthen the structures. Inner plate reinforcement is a relatively new strengthening method compared to conventional reinforcing methods. As there is no corresponding guideline which can be used for the design of inner plate reinforcing joints, it is necessary to investigate the failure mechanism of such tubular structures. Both experimental test and finite element analysis are carried out in this study to investigate the static behaviour of multiplanar tubular joint reinforced with inner plate. In the experimental work, the stresses distribution and development of the specimen is monitored, and the failure mode is observed. From the experimental results, both the failure process of the multiplanar tubular joint and the reinforcing efficiency of the inner plate were analyzed. Using finite element analysis, the failure process of the specimen is also analyzed step by step. The finite element results agree reasonably well with experimental measurements.