Experimental study on seismic behavior of T‐shaped steel fiber reinforced concrete columns

Abstract

Six T-shaped columns in which steel fiber concrete is integrated with a high-strength stirrup (SFRC) and two control specimens are tested under a cyclic lateral load and constant axial load. The effectiveness of the steel fiber concrete and high-strength stirrup to enhance its ductility and earthquake resistance is described at high-and low-axial compression ratios. The failure patterns, hysteresis response, backbone curves, ductility, and strain behavior analysis of the columns are studied systematically in the test. The effects of the stirrup strength, stirrup spacing, steel fiber content, and axial load ratio were investigated. The test results demonstrated that all specimens exhibited flexural failure. Steel fibers could prevent the cracked concrete from spalling. Specimens with high-strength stirrups, close stirrup spacing, and steel fiber exhibited a higher lateral bearing capacity, energy dissipation capacity, initial stiffness, and displacement ductility. A new strength model for predicting the lateral ultimate capacity of T-shaped concrete columns strengthened with SFRC subjected to cyclic loading is proposed. The calculated results agree well with the test results. Eight T-shaped column specimens were simulated using ABAQUS finite element analysis software. A comparison of the results of the numerical study with the experimental results demonstrates that the finite element model can accurately predict the structural behavior.

Investigation on the shear performance of circumferential joints of segments in super‐large cross‐section shield tunnels

“…The embedded constraint method was adopted to simulate the interaction between reinforcement and concrete. 10,17,18,20 The sleeve side of the calculation model was placed on the left, whereas the hand hole side was placed on the right. For the left part of the calculation model, the displacement in the y-direction was limited on the upper and lower surfaces, and the displacement in the zdirection was limited on the right end surface for the right part.…”

“…According to the existing studies, 22 the interaction between bolt and sleeve, sleeve and concrete were set as binding constraint. The embedded constraint method was adopted to simulate the interaction between reinforcement and concrete 10,17,18,20 …”

“…The established calculation model consists of concrete, reinforcement, bolts, sleeves, and gaskets. The concrete, bolts, sleeves, and gaskets are simulated with C3D8R elements, while the T3D2 elements are selected for simulation of reinforcement 10,17,18,20 . The numerical calculation model of the circumferential joint is shown in Figure 3.…”

Experimental Study on Repairing/Restoration and Reinforcement Methods of the Reinforced Concrete Structures Damaged by Earthquakes

“…In 2019, Liu [8] conducted static tests on four reinforced, bent steel columns and one unreinforced, bent steel column for comparison to investigate the effects of the thickness of the affixed steel plate and the load eccentricity on the force performance of the bonded steel reinforcement. The results show that all five bent steel columns exhibited spatial bending and torsional instability damage, and that bonding steel plates outside the flange can effectively improve the out-of-plane stabilization of bent steel columns.…”

Research on Seismic Performance of a Two-Story, Two-Span Underground Subway Station with Split Columns Based on the Quasi-Static Method

“…Li [29] used ABAQUS finite element software to analyze the effect of the separation ratio on the damage mode and load carrying capacity of split columns. In cases where the load-carrying capacity is comparable to that of monolithic columns, split columns exhibit a significant reduction in lateral stiffness and a notable increase in ductility, thereby demonstrating improved deformation and energy dissipation capabilities [30,31]. This feature of split columns is suitable for mitigating seismic hazards of underground structures.…”