| With the development of high-rise buildings, more and more steelflame-concrete corewall mixed structure are applyed. This kind of structure can takefull advantage of steel and concrete, and the anti-vibration ability is excellent. Butwith tall buildings got higher and higher, the problem brought by deformation duringconstruction is getting more serious, the problem not only influences the construction,but also the safety of the structure. Thus, the study on deformation duringconstruction, can improve the design and constructing level, and speed up thedevelopment of economy.Firstly, the time-varying mechanical property of concrete used in high-risestructures was studied. By fitting the test data, the time-varying model of compressivestrength, elasticity and Poisson ration of high-strength concrete were set up. Bycontrasting with test, three creep models were evaluated. The results indicate that themodels of CEB-FIP MC90 and B3 are proper to forecast the creep of high-strengthand high-fluid concrete.The calculating method on vertical deformation during construction of high-risebuildings was discussed. The aged-adjust effective module method (AEMM) cantranslate the complicated creep calculation into pseudo-elastic problem, and largelypredigest the calculation on vertical deformation of high-rise buildings. The influenceof construction process can not be ignored in calculation. Finite element-super finiteelement coupling method accurately simulates the process, and improves thecalculation efficiency. Based on construction process, the vertical deformation duringconstruction is divided to two parts: "already happened values" and "shall happenvalues". Commonly, the former values will be compensated during construction. Themethod provides the theoretical guidance for calculating the compensation values ofvertical beating structure during construction.In addition, the vertical deformation analysis on one 57-floor mixed structurewas performed. The time-varying performance of concrete, the progress of corewall leading construct ahead, and compensating were considered. The calculating resultsindicate that the elastic shorting account for 60% of total deformation at the end ofconstruction. Meanwhile, the proportion of creep and shrinkage were 40%. Due to thecompensation in construction, the cumulate shorting at middle floor was larger thanthat at bottom and top floor. The deformation of steel frame column was larger thanthat of corewall, for bearing most of vertical loads. But creep and shrinkage ofconcrete decrease the differential level. Therefore, the leading construction ofcorewall can put development of creep and shrinkage ahead, and decrease thedifferential level. For beams those connecting corewall and column, influenced bycreep and shrinkage, the minus moment at the end of connecting corewall wasreduced, and the moment at he other end was increased. The influence of creep andshrinkage was more distinct at middle floor than at bottom and top floor. Based oncalculation, Different compensation projects for columns were discussed, and "differlength section compensating method" was proposed.The simplified method for calculating the level deformation of mixed structureduring construction was studied. Based on the construction character, the structurewas divided into "cantilever part" and "integrity part". The simplified plane modelwas proposed based on cooperating-work principle of steel frame and corewall. Thedada needed in calculation was plot to charts for better application. By contrastedwith element method, the simplified method was reliable. The calculating resultsindicate that the level deformation of structure would get larger, with more floor ofcorewall lead ahead.Finally, the construction projects and measure for controlling the deformationduring construction was studied. The method for calculating the floors of corewallleads ahead was proposed. The date of twice-construction of frame can be at theextremum time, when the differential shorting was at comparatively the least value.
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