Analysis And Construction Monitoring Of The Vertical Deformation For High-rise Steel Frame-Concrete Corewall Composite Structure

In recent years, more and more steel frame-concrete corewall composite structures have been used in high-rise buildings. With the increase of the height of building, the influence of the vertical deformation is getting larger. Studies on vertical deformation and vertical deformation difference have attracted more and more concern,since they affect not only the construction plan and quality control,but also the structural safety. The construction analysis and construction monitoring became necessary for a large complex high-rise composite structure.Construction analysis and the whole process monitoring on the stress/strain of key components were carried out for a 56 stories steel frame-concrete corewall composite structure.The effect of loading mode, the time-varying performance of concrete,the construction of corewall in advance,construction load and construction speed on the vertical deformation were considered in the analysis.Results show that if the construction compensation is not taken into account,the cumulative vertical deformation will increase gradually,and reach the maximum at the top of the structure.On the contrary,the vertical deformation at the middle floor was larger than that at the bottom and top floors.In the cumulative vertical deformation during construction,the elastic deformation always accounts for the largest proportion,i.e.62%,and that of the creep deformation of concrete is 30%,shrinkage deformation of concrete is 8%.The more stories of corewall in advance construction is,the more fully that the creep and shrinkage will develop, and the larger vertical displacement of the wall generates, but the influence of this factor on the frame column is just the opposite.The deformation effect of the load is more serious on the column than that on the shear wall, if the floor live load increase 2kN/m2,the vertical displacement of the wall and the column will increase about 10% and 20% respectively.Creep and shrinkage of the concrete corewall can slightly increase the axial force of columns.Monitoring results have recorded the process of strain development of structural members during construction, the regularity of monitoring and simulation results are consistent, however, the numerical differences between them are still larger. In fact, the CEB-FIP90 model has underestimated the shrinkage and creep of concrete, and the simulation accuracy of stage loading construction analysis for composite structure construction is poor.by using SAP2000.Moreover,this paper puts forward the suggestions for the compensation of vertical component deformation based on the structural characteristics and construction features of the research object,and also puts forward the modified compensation value 0' according to the parameters ? and ?0 which are determined by the strain development of the lower monitored floors. At last, some measures are briefly introduced in this paper to control the vertical deformation from structural design and construction aspects.The three major innovative points of this paper are summarized as follows:?The author has carried out the construction monitoring on the real structure, monitoring work lasted for 18 months,and this paper has conducted its research work from both structure measurement and simulation analysis aspects,the previous studies,paid too much attention to the method of software simulation,but the research of structure measurement of real structure is very few,so that it is difficult to obtain the accuracy of the simulation method;?The author has used the monitoring means to show how the stress change at the end of the beam was affected by the shrinkage and creep of concrete wall and the deformation caused by structural load the first time;?In this paper,a modified method of vertical deformation compensation is proposed, which is based on the strain development of the lower monitored floor.