Research On System Judgment, Reasonable Stiffness And Torsion Calculation Of Tall Building Structures

With the development of economy and the progress of technology, the development speed of tall building structures increases year by year, the height is increasing continuously, the function and the style are becoming complex more and more, the structural systems are becoming more various. The various structural systems have the emblematical behaviors and the corresponding methods, the concerned problems are also different during the design. It is necessary to quantificationally analyze the parameter critical value of the different structural systems. During the practical engineering, it is wish to obtain the maximum stiffness and the best structural behaviors based on the limited material dosage, which is involved the structural reasonable stiffness and reasonable arrangement of elements. At the same time, when the plane arrangement or the shear wall is complex and asymmetry, the tall building structures not only have the parallel move, but also the torsion around their stiffness center. It is shown from the seismic disaster that torsion effect is a very important factor to harm the tall building structures. In this paper, the key problems of the system judgment, reasonable stiffness and torsion calculation of tall building structures were studied as follows.1.The rule of judgment the structural system which was the frame-tube structures or the common frame structures was brought out. The critical ratio of beam's span to height was obtained by the equal topmost side-sway of two structures. The structure should belong to frame structures when its ratio of beam's span to height exceeds the critical ratio. Otherwise, it should belong to frame-tube structures.2.There are two stage weighted systems in mage-frame structure. The lateral rigidity ratio of main frame to the hypo-frame is the main factor which affects the weighted performance of mage-frame structure. The partial frame was selected from adjacent main frame beam as analysis element, and its lateral rigidity was calculated by displacement ponderance method. The optimal range ofαwhich was the linear rigidity ratio of one main frame column to one hypo-frame column was studied, and the rule of judgment the structural systems which was the mage-frame structures or the common frame structures was brought out. The hypo-frame structures was studied by this method, which can the influence factors such as the analysis element story n, span quantity m , hypo-frame beam-column ratio i次, main frame beam-column ratioi主.