This paper examines accuracy and applicability of the modal-explicit technique in numerical experiments and the New Hybrid Aerodynamic Vibration Technique. The modal-explicit technique is a numerical integration technique which is combination of Newmark Explicit method with modal truncation technique in order to secure stability of solution and simple algorithm. In the numerical experiments, the accuracy of solution is verified by using three types of lumped-mass model. It is difficult for a numerical integration technique to obtain stable solution because all the models include high frequency vibration modes. The hysteretic curve in the each story has non-linearity. The random vibration behavior is followed by the modal-explicit technique, the accuracy and stability is satisfied. In the New Hybrid Aerodynamic Vibration system, that is set in the modal-explicit technique as a numerical integration technique, unstable wind response of a base-isolated high rise building is simulated. The accuracy is satisfied, too.

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Wind loads for designing thin circular cylindrical structures, such as oil-storage tanks and silos, have been studied in a turbulent boundary layer, aiming at accumulating information for the revision of the AIJ Recommendation for Storage Tanks and Their Supports (1996). Wind pressure distribution on the roof, in the case of enclosed structures, was measured, the results of which are compared with the specifications of the AIJ Recommendations for Loads on Buildings (2004). The effects of open top on the pressure distributions on the external and internal wall surfaces are also investigated. Furthermore, the characteristics of instantaneous pressure distributions on the external surface are discussed by using a conditional sampling technique and the POD (Proper Orthogonal Decomposition) analysis.

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