Seismic behaviour of RC columns with lap-spliced crossties under various axial loads

AbstractThis paper studied the confinement effect of textile layers and the stirrup ratio on the seismic behaviour of TRC-strengthened RC columns using the numerical method. The results showed that the numerical values have good consistency with the experimental. Within the range of 1 to 3 layers of textile, with the increase of the number of textile layers, the peak load, displacement ductility ratio and energy dissipation capacity of the columns increased; however, these parameters only exhibited a limited increase when the textile layers continued to increase. In addition, the textile layers had a slight influence on the rate of the energy dissipation capacity. With the increase of the stirrup ratio, the yield load, peak load and ultimate load of the column did not change significantly, but the ductility coefficient and energy dissipation capacity of the column increased. Furthermore, for a TRC-strengthened column with three layers of textile and a stirrup ratio of 0.34%, the hysteresis loop fullness and the bearing capacity are better than those of a column with two layers of textile and a stirrup ratio of 0.67%. Therefore, it can be seen that TRC could play an efficient constraint role on the column when the stirrup arrangement is less.

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Seismic Behaviour of RC Columns Strengthened with Steel Bar/Wire Mesh Mortar

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.539.108 ◽

2013 ◽

Vol 539 ◽

pp. 108-114

Author(s):

Yan Hua Sun ◽

Xio Yong Wu ◽

Guang Jing Xiong

Keyword(s):

Failure Modes ◽

Axial Loading ◽

Concrete Columns ◽

Reinforcement Ratio ◽

Wire Mesh ◽

Seismic Behaviour ◽

Rc Columns ◽

Steel Bar ◽

Hysteretic Characteristics ◽

Seismic Bearing Capacity

In order to enhance the seismic behavior of reinforced concrete (RC) columns more efficiently, a thought to strengthen concrete columns by using steel bar/wire mesh mortar （FS）was proposed. An experimental study including five RC square columns strengthened with FS and steel bar mat mortar (S), respectively, under constant axial loading and lateral cyclic loading was carried out. Seismic bearing capacity, ductility, failure modes and hysteretic characteristics of all columns were tested, and the effect of reinforcement ratio and strengthening method to the tested columns was analyzed. The results showed that the energy dissipation capacity of FS strengthened columns was 73% higher than that of the S strengthened column, though the reinforcement ratio of the former was only 3.02% higher than that of the latter.

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Study on Ultimate Bearing Capacity of Reinforced Concrete Columns Combined with FRP

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.94-96.820 ◽

2011 ◽

Vol 94-96 ◽

pp. 820-825

Author(s):

Sai Wu ◽

Jun Hai Zhao ◽

Xue Ying Wei

Keyword(s):

Reinforced Concrete ◽

Bearing Capacity ◽

Concrete Columns ◽

Ultimate Bearing Capacity ◽

Axial Loads ◽

Strength Theory ◽

Rc Columns ◽

Reinforced Concrete Columns ◽

Unified Strength Theory ◽

Good Agreement

This paper based on the unified strength theory, analyzed the ultimate bearing capacity of the reinforced concrete columns combined with FRP under axial loads. First, analyzed the mechanical property of the RC columns combined with FRP. Second, based on the unified strength theory, deduced the three-direction compressive stress of the core concrete and got the unified formula for calculating the ultimate bearing capacity of RC columns combined with FRP. Last, compared the analytical results obtained in this paper with the relevant experimental data, good agreement can be found and it proved the good applicability of the formula. Comparing with other methods in calculating the ultimate bearing capacity of RC columns combined with FRP，this method is well-founded, so it has a significant value in analysis of RC columns combined with FRP.

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