Study On Seismic Performance Of High Strength Reinforced Concrete Columns Which Performance Controllable In Intelligent Building

Nowadays, the earthquakes happen frequently, which pose a serious threat to people's lives and property and bring about great difficulty to the post-earthquake reconstruction work. Therefore, it is significantly meaningful to develop a reinforced concrete structure which has small residual deformation and great deformation capacity, providing stable increased carrying force even in the large deformation regions. Development and study on the reinforced concrete structure aforementioned will become an important research program in the next generation building. In this program the high strength steel rebar having low or no bond stress will be used as longitudinal rebar of concrete structure, and steel plates lay inside of concrete members will be used to control the performances of the resilient concrete structure having self-centering. A new type of high strength reinforced concrete structure is developed based on the Unbounded high-strength steel and internal anchoring steel plate.This paper presents the experiments of concrete columns with unbonded high-strength steel under low-cycle repeated loads. The influence of stirrup ratio and the length of unbonded zone which affect specimens' seismic behavior and re-centering behavior have also been discussed. Besides, the characters of hysteresis and skeleton curve have been researched. Displacement ductility factors, energy dissipation factors and the coefficient of re-centering behaviors have also been calculated.The main conclusions drawn from the experimental results are as follows: compared to the specimen with general bond strength, the re-centering behavior of the non-cohesive column is better while the slip phenomenon is more obvious. The higher the stirrup ratio,the higher the bearing capacity of the specimens. Increasing the stirrup ratio of the specimens can effectively improve their ductility, extending the length of unbonded zone is also the same. The higher the stirrup ratio, the longer the length of unbonded zone, the smaller the residual deformation, the better the re-centering behavior.Finally, combining the influence of displacement and stirrup ratio with displacement and the length of unbonded zone respectively, and taking the variation law of the coefficient of re-centering behaviors into consideration,the evolution model of the coefficient of re-centering behaviors respect to stirrup ratio and the length of unbonded zone is established.