Seismic Performances of SRC Special-Shaped Columns and RC Beam Joints Under Double-Direction Low-Cyclic Reversed Loading

Xiangyu Zhang,Zhiheng Deng,Qing Xia,Ping Xiang,Bailong Ye,Weiran Yan

doi:10.3389/fmats.2021.761376

Abstract

Steel-reinforced concrete (SRC) special-shaped column and beam frame structure is a special structural form that can meet the requirements of high bearing capacity and satisfy the esthetic requirement of buildings. In this study, a new joint design approach is adopted to focus on the seismic behavior of SRC special-shaped column and reinforced concrete (RC) beam joints under low-cyclic double-directional reactions through pseudo-static tests with a controlled stirrup distance. The joints of SRC specimens were compared with those of RC specimens by controlling the area of steel and reinforcement, and hysteresis cycle skeleton curves and load and strain hysteresis cycles were analyzed. The specimen with profiled steel was found to have better energy dissipation capacity. The energy dissipation capacity and stiffness degradation of the nodes were analyzed. The test results showed that the energy dissipation capacity of the SRC joints was better than that of the conventional concrete column joints, and the stiffness degradation of RC joints was more significant than that of SRC joints.

Highlights

Steel-reinforced concrete (SRC) special-shaped columns are more esthetically pleasing than the traditional rectangular columns of frame structures and can meet the requirements of architectural design
We found that the joint of the steel-reinforced concrete special-shaped column and reinforced concrete beam had relatively small crack width and large stiffness
The special-shaped column structure solves the problem that the corner of the traditional frame structure affects the indoor architectural decoration due to the excessive column section, so it has been widely used in practical engineering

Summary

Introduction

Steel-reinforced concrete (SRC) special-shaped columns are more esthetically pleasing than the traditional rectangular columns of frame structures and can meet the requirements of architectural design. Compared with traditional rectangular columns, the application of special-shaped columns is more complicated and restricted. Special section shapes such as L-shaped, cross-shaped, T-shaped, and Z-shaped are usually used instead of the traditional rectangular section, so the ductility, bearing capacity, and seismic performance of shaped columns, especially the structural joints, are of great concern (Park, 2002). Experimental studies on the shear bearing capacity and seismic performance of reinforced concrete (RC) beam and column joints are necessary (Ma et al, 2019; Cao et al, 2021; Deng et al, 2021). Many researchers have conducted experimental studies on shear capacity, seismic performance, or mechanical behavior of square RC columns (Huang et al, 2019), T-shaped (Zhang et al, 2019; Deng et al, 2021), L-shaped (Chen et al, 2021a; Chen et al, 2021b), and other shaped columns connected with reinforced concrete beams

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Results

Conclusion