Research On Bolted Connection And Residual Stress In Fabricated I-section In Structural Stainless Steel

The production of stainless steel in China has ranked first in the world since2006. More stainless steel are used in building structures with the increase of the production and the improvement of the processing technology in our country. However, the fact that there are few comprehensive studies on stainless steel structures is not suitable for the application of stainless steel in structural engineering in China. There has not been a specification or code for stainless steel structures in China, which has seriously limited the development in civil engineering. This paper investigates some performance of bolted connection in stainless steel and the residual stress in stainless steel fabricated I-sections, providing the experimental data for the preparation of "Specification for stainless steel structures" in China.Firstly, comparative study on design methods for bolted connection of stainless steel in different codes is investigated, including European (Eurocode3EN1993-1-4), American (SEI/ASCE8-02), Australian/New Zealand(AS/NZS4673) standards, Japanese design code for stainless steel structure. Bolted connection for stainless steel is contrasted in the design process, including the resistance of net cross-section, the bearing resistance, the shear resistance, the tension resistance of the bolt connection, and the resistance under combined shear and tension. The related example in calculation is given and the results of the design are compared. The results show that the European code is detailed, the Japanese code is relatively comprehensive, and that it is not proper that GB50017-2003is applied in the design of bolted connections in stainless steel structures. Further systematic research should be carried out.Secondly, ANSYS is carried out to found the model and analyze the bearing performance of bolted connections in stainless steel, considering the influencing factors including the thickness, the end distance and the diameter of the bolt. Based on the FEA, experimental study on the performance of bolted connections in austenitic stainless steel316is carried out, which is compared with the same level of stainless steel designated1.4401in Europe. The test results were compared with the results of the finite element analysis, and the comparison proved the validity of the FEM. The design formula of bearing capacity of bolted connections in stainless steel was proposed based on the parameterized finite element analysis.Besides, this paper investigates the strain relaxation of the bolts in stainless steel and the anti-slip coefficient in slip bolt joints with stainless steel, including4kinds of friction surface processing and3types of bolts:friction surface treatment——wire drawing, abrasion blasting, scoring, non-processing; bolt type——grade10.9, A4-70, A4-80.28preloaded bolts from12specimens have been monitored for more than47hours. The time-dependent rule of the strain of the bolts has been compared and analyzed. Proposals for the application of preloaded bolts in stainless steel and the torque check of preloaded bolts in stainless steel have been presented. The anti-slip coefficients of the12specimens have been determined, providing experimental basis for the application of preloaded bolts in stainless steel structures.In addition, this paper also studies the residual stress of austenitic stainless steel in fabricated I-sections. An experimental study on the residual stress of the austenitic stainless steel316(06Cr17Ni12Mo2) is conducted by sectioning method with6types of sections included. The distribution and magnitude of austenitic stainless steel316fabricated I-sections have been analyzed. A new residual stress model for austenitic stainless steel316fabricated I-sections has been proposed, serving a base for further study on the effect of the residual stress on stainless steel components.