Theory And Applications Of Dynamic Reliability Of Steel Braced Frame Structures Of Tall Buildings

In order to get structures enough safe as wellas economical, engineers have to do designings according to the theories of probability and reliability as strictly as possible. With wide use of steel structures in tall and super-tall buildings, the problems of SOFT of structuers become more outstanding. It will face massive challenge in theory to study the dynamic reliability and controlling of anti-wind and anti-seismic structures, but great benefit may achieve in economy.This paper study nonlinear dynamic reliabilities of anti-wind and anti-seismic steel braced frames of tall buildings. Firstly, by using M. F. Giberson single component model, the element stiffness matrix possessing the second-order effect, material nonlinear and element shearing deformation is deduced. After studying in detail on the behavior of the panel, the effect of the panel deformation is brought into the relevant element stiffness matrix. With applying member-story vibration model and direct-stiffness method, the structural nonlinear vibration quation is established. Secondly,based on the analyses of random dynamic response of anti-wind structures, the structural reliabilities of safety and comfortability are studied contrastively. Combining with the caculation result of examples, it is found that steel tall-structures usually achieve reliability of safety more easy than that of comfortability. Comfortable reliability was generally ignored, however it impair the nomal usage of building. Thirdly, the dynamic response formulas of steel tall structure controled by TLD are derived; the effects of TLD's parameters on the control efficency are analysed; an optimization procedure for the TLD's designing is proposed; and suitable ranges of TLD's parameters are given out. Caculation examples show that TLD is an efficrent and economical controlling device. Finally, the function concerning a (yield stiffness coefficient of stucture) with μ (displacement elongation of structure)is presented; thus formulas of equivalent stiffness and equivalent damper are obtained. After analysing eathquake-induced nonlinear random response, the relevant reliability is derived. In caculating examples, the effects of second-order and soil classification on the reliability are discussed.All of the studies in this paper are carried out according to current codes and the sampels are typical and applicable, so the deduced results are valuable both in theory and practice.