Interstorey Shear Force Distribution Of High-rise Buildings Under Horizontal Loading

With economic development, a growing number of high-risebuildings are built in China. Frame-shear wall structures and frame-coretube structures are widely used as high-rise buildings’ two major forms.For high-rise buildings, horizontal loadings (including wind and seismiceffects) have very great influence. Because China is an earthquake-pronecountry, the study of interstorey shear force distribution of high-risebuildings is of great significance for improving the seismic analysis andthe design of high-rise buildings. The study can also ensure the safety ofthe structure in the earthquake, in order to reduce personnel and propertylosses in the earthquake.Firstly, the existing frame-shear wall work together theoreticalmodel is improved, and the improved model is used to study theinterstorey shear force distribution of the undamaged structure. Variousparameters in the theoretical model for interstorey shear force distributionare analysised, and the main factors to determine the interstorey shearforce distribution are identified. Based on the model, how the shear walldestruction caused changes in the seismic force and interstorey shear force distribution is studied. The seismic forces in the frame after theshear wall destruction are calculated, and compared with the adjustmentvalues in the design codes. Then the interstorey shear force distributionsfor an actual project in frequent earthquake and rare earthquake arestudied and compared with the previous results obtained by analyticalmodel analysis.From the comparative analysis, conclusions are obtained that whenstructure is undamaged, the distribution of interstorey shear force ismainly determined by the frame shear-wall stiffnesses ratio and the loaddistributions. When the structure is damaged, seismic forces decrease dueto longer structural period, but frame shear forces greatly increase, andthe frame shear forces are likely to exceed the design values. The currentadjustment method may not guarantee that the frame can prevent theseismic collapse of the structure.