| Earthquake is a natural phenomenon, which has the character of wide range, drastic damage, and unpredictability, is a disaster which may cause extremely danger to people’s life and properties. Besides, China is located between Eurasia seismic zone and circum pacific seismic zone, which suffers a lot from earthquakes.Frame structure has the advantage of light quality, homogenous material, good plasticity and toughness and convenient installation, and adopted widely in civil engineering. In steel structure system, the joint, connecting a component with another, as the key for the steel structure frame, is a top priority in the steel structure design. This thesis studies the new joint with extend reinforce rings which is based on the theory of shift-away of plastic hinge. The new joint is to insert the beam between upper and lower reinforcement ring plate contacted with the square steel tube column. Welding steel beam and steel column, steel beam and reinforces ring plate, square steel tube column and reinforcement ring plate welding respectively.Based on the mid-span beam-column joints studies, this dissertation adapts the finite element analysis software ABAQUS to simulate and calculate the experiment patterns and compare the result to verify the reliability of the finite element model. Furthermore, changing the parameters of joint computing to analyze the influence of different parameters on the stress nephogram, hysteresis curves, skeleton curves, stress curves and so on. On this basis, the author develop the side span concrete beam-column joints strengthened form of a ring.The main results are as follows:(1) Constitutive relations of material, reasonable size, exact boundary conditions, and loading regimes should be adopted while calculating by software to make the result more reliable.(2) Strengthening ring plate reduction calculations, stress failure pattern and mechanical properties of JD-01 ~ JD-06 are basically the same. While, the stress rupture cloud and stiffness degradation of JD-07 has a more significant difference. The failure modes of JD-08 are welded parts. It is determined to strengthen the ring plate cut in half for the right side of the cross beam-column joints form. It is basically the same in terms of mechanical properties and is not reduced, and there is a sufficient safety margin at the time of the actual processing to be sufficient to save steel.(3) Strengthening ring plate cutting angle form calculations, stress failure pattern and mechanical properties of QJ-01 ~ QJ-03 are basically the same. The cloud stress damage, hysteresis curves, skeleton curves and the strengthening of the stress distribution ring plate of QJ-04 has a significant difference. Therefore, the side span reinforcement ring plate chamfer form beam-column joints using 45 ° cutting angle, both to ensure the mechanical properties of the node, but also save steel.. |
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