Research On The Wind-excited Vibrations And Static-equivalent Wind Loads Of Torsionally Coupled High-rise Buildings

Based on the simultaneous pressure wind tunnel test, profound researches on three dimensional(3-D) wind-induced response as well as their static-equivalent wind loads of torsionally coupledhigh-rise buildings are included in this dissertation and the corresponding calculation system isestablished. The research is summarized as follows:1) Eleven typical rigid high-rise building models are used in the simultaneous pressure windtunnel test. Characteristics of base bending moment and torque are studied based on the test results.Wind forces distributed on different levels are also studied. The abovementioned researches arethe basis of further researching on wind-excited responses and static-equivalent wind loads.2) By using nonlinear least-square method, a series of formulas about wind forces acting onrectangular high-rise buildings are obtained. All these formulas are checked by comparingthem with the data in literature.3) In terms of the basic principle of high frequency force balance (HFFB), a method forsimulating spatially distributed wind forces acting on tall buildings is presented. Simulatedgeneralized wind forces for the first nonlinear and the second mode shapes are compared with theresults directly calculated from experiment data. The comparison results verify the precision of thepresent method.4) Based on existed research results, the torsionally coupled high-rise building is reduced tomonolayer systems. The effects of frequency ratio of bending to torsion, correlation betweenacross-wind and torsion wind forces, side ratio of cross-section, wind field and wind velocity onthe first mode responses are investigated. Basic characteristics of second mode accelerationresponses are also studied with varying distances between the centers of mass, rigidity andgeometry. An approximate method for the wind-induced coupled responses is developed at last.5) By introducing mode coupling coefficients, a modified SRSS method is proposed tocalculate resonant components of the responses and the resonant static-equivalent wind loads.Using the basic conception of Load-Response-Correlation (LRC) method, formula of threedimensional background static-equivalent wind load is derived. The background and resonantstatic-equivalent loads are combined with weight factors. The consequential total equivalent windload is verified through theoretic prove and numerical results.