Shrinkage And Creep Analysis Of High-rise Structure Based On ABAQUS

At present, high-rise buildings are increasingly adopted along with the rapidpopulation growth and the rapidly-developed economy, the influence of shrinkage andcreep of concrete becomes exceedingly evident therewith the augment of dead load, aswell as the elongation of the construction cycle, therefore it’s of great significance tostudy the vertical internal force redistribution and the differential shortening of verticalmembers in high-rise buildings, considering the staged construction process and concreteshrinkage and creep. Three buildings of different structure system, including a11-storyRC plane-frame structure, a40-story steel frame-RC core wall structure and a20-storyall concrete frame-core wall structure, were analyzed by using nonlinear stagedconstruction method considering shrinkage and creep, and the article is organized asfollows:It Compiled the calculation program of shrinkage and creep based on theintegral-type approach by MATLAB language, then simulated the experimentaltime-dependent axial-strain curve of the concrete short column under the step-wiseloading which is conducted by Harbin Institute of Technology. Furthermore theexperimental curve was taken into comparison, and the rationality of the analytical resultwas validated. The suitable prediction model of creep and shrinkage of concrete waschosen.Shrinkage and creep effects on a reinforced concrete column with the axialcompression ratio equal to0.54, was calculated by the general-purpose FEcode-ABAQUS-integrated with user-defined subroutines USDFLD and UEXPAN, thencomparison was made with the calculation results of documents available, validating theselective prediction model and the algorithm. Moreover, the sensitivity of parameters,such as reinforcement ratio, concrete strength, was discussed. And the rationalreinforcement ratio was proposed.Three medium and high-rise buildings with different structure system, which is a11-floored plane frame structure, a40-floored steel frame-core wall structure and a20-floored concrete frame-core wall structure were designed to conduct the analysis withthe simulated construction process and shrinkage-and-creep, the variable curves ofvertical displacement and vertical displacement differentials, the internal forceredistribution curve between steel-columns and the core-wall were obtained, which are caused by creep and shrinkage. It reveals that the vertical shortening increases two tofour times larger than the initial shortening; on the1st floor of the plane-frame structure,the value of the bottom moment of the side-column has increased by3times; The axialinternal force of the mid-column in the40-story hybrid structure has increased by45%.The sensitive analysis of different parameters, like construction cycle, environmenthumidity, the considering of the in-advanced construction of core-wall in hybridstructure, was conducted. Some advices on the construction procedure of high-risebuildings were proposed.