An experimental study on the compressive behavior of steel fiber reinforced concrete-filled steel tube columns is presented. Specimens were tested to investigate the effects of the concrete strength, the thickness of ...An experimental study on the compressive behavior of steel fiber reinforced concrete-filled steel tube columns is presented. Specimens were tested to investigate the effects of the concrete strength, the thickness of steel tube and the steel fiber volume fraction on the ultimate strength and the ductility. The experimental results indicate that the addition of steel fibers in concrete can significantly improve the ductility and the energy dissipation capacity of the concrete-filled steel tube columns and delay the local buckling of the steel tube, but has no obvious effect on the failure mode. It has also been found that the addition of steel fibers is a more effective method than using thicker steel tube in enhancing the ductility, and more advantageous in the case of higher strength concrete. An analytical model to estimate the load capacity is proposed for steel tube columns filled with both plain concrete and steel fiber reinforced concrete. The predicted results are in good agreement with the experimental ones obtained in this work and literatures.展开更多
This paper investigates the strength and deformation characteristics of reinforced normal and high-strength concrete rectangular beams which failed in shear and repaired by external bonding of carbon fiber and steel p...This paper investigates the strength and deformation characteristics of reinforced normal and high-strength concrete rectangular beams which failed in shear and repaired by external bonding of carbon fiber and steel plate. Five simply supported reinforced concrete beams with shear reinforcement are tested, three of which are made with NSC (normal-strength concrete) and the other two with HSC (high-strength concrete). The span of the simply supported beams is 0.9 m with 100 mm wide by 200 mm deep cross section. All five beams are tested under four-point bending. Careful repair process is adopted and proved successful. The aim is to restore or increase shear strength of these beams and to monitor their post-repair load-deflection behavior. The effect of concrete compressive strength on the behavior and strength of beams before and after repair is also investigated. Shear cracks patterns and their evolution are observed and discussed.展开更多
基金Project(51078294)supported by the National Natural Science Foundation of ChinaProject(201101411100025)supported by the Doctoral Fund of Ministry of Education of China
文摘An experimental study on the compressive behavior of steel fiber reinforced concrete-filled steel tube columns is presented. Specimens were tested to investigate the effects of the concrete strength, the thickness of steel tube and the steel fiber volume fraction on the ultimate strength and the ductility. The experimental results indicate that the addition of steel fibers in concrete can significantly improve the ductility and the energy dissipation capacity of the concrete-filled steel tube columns and delay the local buckling of the steel tube, but has no obvious effect on the failure mode. It has also been found that the addition of steel fibers is a more effective method than using thicker steel tube in enhancing the ductility, and more advantageous in the case of higher strength concrete. An analytical model to estimate the load capacity is proposed for steel tube columns filled with both plain concrete and steel fiber reinforced concrete. The predicted results are in good agreement with the experimental ones obtained in this work and literatures.
文摘This paper investigates the strength and deformation characteristics of reinforced normal and high-strength concrete rectangular beams which failed in shear and repaired by external bonding of carbon fiber and steel plate. Five simply supported reinforced concrete beams with shear reinforcement are tested, three of which are made with NSC (normal-strength concrete) and the other two with HSC (high-strength concrete). The span of the simply supported beams is 0.9 m with 100 mm wide by 200 mm deep cross section. All five beams are tested under four-point bending. Careful repair process is adopted and proved successful. The aim is to restore or increase shear strength of these beams and to monitor their post-repair load-deflection behavior. The effect of concrete compressive strength on the behavior and strength of beams before and after repair is also investigated. Shear cracks patterns and their evolution are observed and discussed.