Study On The Eccentric Compression Behavior Of Confined Concrete Column With High-strength Longitudinal Reinforcement

As the main structure form in our country, concrete construction is used in civilengineering extensively. In the materials used in construction engineering, steel andconcrete is used most. Reinforced concrete structure developed relatively slowly inthe field of civil engineering. In our country, widely used in building engineering ofthe strength grade of concrete is C20~C40, longitudinal carrying bar is HRB400,and stirrup is HPB300. They are all under the level of developed country. For a longtime, our country constantly take a series of measures to promote the application ofhigh strength steel and high strength concrete in the construction trades. But the useof high strength steel and high strength concrete is still low in the building materials.The main reason is that theoretical study of high-strength material falls behind.At present, test and finite element analysis about constraints of concrete axialcompression member are more, but the study of High strength reinforced constraintson high strength concrete eccentric member are relatively fewer. The study aboutwhether the strength of high-strength longitudinal reinforcement configuration in theconfined concrete could play, and how much influence of high-strength longitudinalreinforcement on the bearing capacity and deformation of the components is still notsystemic.Our text use the ANSYS finite element numerical simulation method to studyhigh strength reinforced high strength concrete member under eccentric loading fromaspects of concrete strength, stirrup strength, stirrup spacing, stirrup form, theintensity of longitudinal reinforcement, the ratio of longitudinal reinforcement,eccentric distance and so on. It reveals the high-strength longitudinal reinforcementeffect on bearing capacity and deformation, and put forward the suitable for highstrength restrained reinforced high strength concrete eccentric component bearingcapacity calculation formula.By comparing different factors influencing on the bearing capacity anddeformation of eccentric compression member, it turns out that stirrup has the mostinfluence on member. Reducing the stirrup spacing could improve the bearingcapacity and deformation performance of components effectively and make opportunity to the high-strength longitudinal reinforcement configuration in thecomponents. When the component of stirrup spacing is50mm, componentsconfigured in the1000MPa of longitudinal reinforcement can be up to1000MPawhen reinforced concrete strength in the component reaches the peak strength,improving20%of the capacity more than components configured in the400MPaof longitudinal reinforcement. When stirrup spacing does not change, different stirrupform，longitudinal reinforcement ratio, and concrete strength could affect the bearingcapacity. In curve segment, as stirrup strength reaches a certain value, improving thestrength of the stirrup has no effect on the performance of the component.By analyzing the various factors affecting the bearing capacity of eccentriccomponent, combining with the results of numerical simulation and test, and withreference to ordinary formula of eccentric compression bearing capacity ofcomponents, in high strength reinforced high strength constraints the bearing capacityof components, stirrup are considered in the formula to calculate the bearing capacityof eccentric compression member. The calculated value is closer to the actualsituation.