Seismic Analysis Of The Double-tower Structure With Enlarged Base And Energy Dissipation Of Eccentrically Braced

The double-tower structure with enlarged base is a unique style and an innovative structural system. The structure is designed and constructed by people more and more. The existence of the double-tower structure makes the mechanical properties of the structure more complex than the ordinary high-rise buildings. The framework is a relatively common form of structure in high-rise buildings. The double-tower structure is designed as a frame structure in terms of lacking of sideways resistance capacity. It can be a good solution to this problem that we add bracings to the direction of the lateral force. There are two forms of bracing including central braced and eccentrically braced. We use the eccentrically braced as the predominant position of the lateral force component in the double-tower, so the double-tower and the eccentrically braced combine into a new model. We can improve the seismic reliability of the new model, seismic behavior of the new model is superior. It is easy to achieve the basic principles of the seismic design of buildings which is no damage in small earthquake,repairable under moderate earthquake,no collapsing with strong earthquake.We use the beneficial software SAP2000 to analyze the seismic response analysis of the structure with an example of 22 layers of two different programs. Firstly, we do the modal analysis to the different programs in order to get the natural vibration periods and the first nine vibration modes. Secondly, we input three earthquake waves including EL-Centro wave,Taft wave,Lanzhou 1 wave to do the time history analysis. The directions of the waves are X and Y. Through the data and charts we compare and analyze the variations of s set of earthquake reactions following different waves and different active directions of earthquake waves. Subsequently we find the laws and summary conclusions:(1) The result of the modal analysis shows: The same point: No matter the eccentrically braced system or the central braced system, the vibration forms of the structures are varied;(2) The result of the time history analysis shows: Form the time history analysis we can get the top floor's absolute acceleration curve,the top floor's velocity curve,the maximal story displacement curve and the maximal interlayer displacement curve. From the curves and the data we know different earthquake waves and different active directions of earthquake waves can lead to different earthquake responds, mainly embody in the different maximal value of the earthquake responds and different time of the appearance of the maximal value; the ability of the dissipation energy of eccentrically braced system is stronger, so the earthquake responds of the whole structure is lighter than the central braced system.