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A novel composite joint with corrugated web and cover plates for simultaneously improving anti‑collapse resistance and seismic behavior

Wang Jing-Xuan, Wang Wen-Qi, Gao Shan

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e77, 2023

EN

This paper presents a numerical study on the progressive collapse response of concrete-filled steel tube (CFST) composite joint. A novel beam-column connection by using corrugated web and cover plate is proposed to enhance the collapse resistance of the joint. The simulated response is evaluated in terms of the ultimate load and deformation capacity of the joints for column removal scenario and cyclic loading. The results indicate that the corrugated web and cover plates connection can effectively delay the local buckling and fracture of the steel beam. Those configuration details have a significantly positive effect on the development of internal force, especially in the catenary mechanism stage to provide tensile force. Moreover, only after the fracture of the bottom fange, the corrugated web of the beam begins to contribute to the anti-collapse capacity of the joint. Compared with the CFST column-steel beam joint with fat beam web, the anti-collapse capacity and the vertical displacement of the joint are increased by 75.9% and 92.8%, respectively. Furthermore, a simplifed calculation method for the anti-collapse capacity of the joint is proposed according to the resistance mechanism analysis. In addition, the seismic evaluation of the novel joint based on anti-collapse design indicates that the novel connection details can signifcantly improve the collapse resistance of the joint, without impairing its seismic resistance.

2

Performance of circular stainless‑carbon steel tube confned concrete stubs under axial compression

Gao Shan, Guo Lanhui, Zhang Sumei

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 3

art. no. e104

EN

To increase the usage cost-efectiveness of stainless steel in structural members, a bimetallic tube composed of an external thin-walled stainless steel tube and an internal relatively thick-walled carbon steel tube is proposed. Fifteen stub specimens including nine stainless-carbon steel tube confned concrete (SCTCC) stubs and six concrete-flled stainless-carbon steel tubes (CFSCT) were tested and analyzed in detail. The results show that both SCTCC stubs and CFSCT stubs exhibit good mechanical performance and shear failure modes. The axial strength of SCTCC stubs is higher than that of CFSCT stubs. Regarding SCTCC stubs, the exterior stainless-steel tube would yield before the interior carbon-steel one. The parametric analysis shows that the rising in the thickness ratio of stainless steel tube would decrease the axial capacity of SCTCC model, but also cause the decrease in the axial resistance of the model beyond the peak to become more subtle. The predicting method regarding the capacity of SCTCC stub under axial compression is proposed based on the current design standard and test results.

3

Real-time hybrid test of a LNG storage tank with a variable curvature friction pendulum system

Lin Shu-chao, Wang Jingxuan, Gao Shan, Zhao Hong-tie

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

44--62

EN

To accurately reproduce the seismic response of the liquefied natural gas (LNG) storage tank equipped with the variable curvature friction pendulum system (VCFPS), a real-time hybrid (RTH) experiment, also known as a real-time substructure experiment, is conducted on it in this study. A typical LNG storage tank with a capacity of 160,000 m3 is employed as the numerical substructure simulated using the MATLAB/Simulink, while the variable curvature friction pendulum bearing (VCFPB) is utilized as the experimental substructure tested using the compression-shear equipment. Thereafter, the validity and feasibility of the RTH experiment are verified using the SAP2000 results. Finally, the working performance of the VCFPB is evaluated scientifically, comprehensively, reasonably, and efficiently. The results show that the VCFPB is very effective in avoiding the resonance phenomenon. It can be seen from the displacement of isolation layer that the VCFPB meets the design requirement. The maximum relative deviations between the RTH test results and the SAP2000 results are 3.45% for the displacement of isolation layer, 4.27% for the base shear, and 1.49% for the liquid sloshing height, respectively. The RTH test is stable and reliable and the predicted results are highly accurate and effective. The RTH test method proves to be accurate in the prediction of the seismic response of the LNG storage tank equipped with the VCFPBs.

4

Performance of circular bimetallic tube confined concrete slender columns under eccentric compression

Gao Shan, Guo Lanhui

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 2

13--39

EN

This paper aims to investigate the performance of thin-walled circular stainless steel-carbon steel bimetallic tube confined concrete slender columns under eccentric compression. 14 slender columns including bimetallic tube confined concrete (BTCC) with and without rebar, and concrete-filled bimetallic tube (CFBT) were tested. A parametric analysis is conducted based on the validated finite-element model. The results show that the two steel tube layers worked well together and the thin-walled BTCC specimens behaved in a ductile manner. Under the same parameters, the decrease of the diameter–thickness ratio of bimetallic tube improves the bearing capacity and rigidity of the BTCC slender column, but reduces its ductility in the descending stage. The confinement effect of bimetallic tube on the concrete in BTCC columns is stronger than that in CFBT columns. When the yield strength of stainless steel and carbon steel is similar, the stainless steel–total steel ratio has little effect on the capacity of the column. Provided meeting the requirements of corrosion resistance, relatively thinner stainless steel tube is preferred to reduce the cost. The comparison between the simulation and the calculation results shows that the current design method can predict the bearing capacity of the BTCC slender column with large diameter–thickness ratio.