We presented the statistical specifications of the pressure patterns in the typhoons through the analysis by the Schloemer's formula (1954) in the moderate and severe typhoons which had made landfall on the Japanese main islands during the period 1951-1984. Basing on these specifications, we synthesized a stochastic typhoon model, and carried out the simulation of typhoons by the Monte Carlo technique. Further, a series of simulated typhoons was applied to the estimation of the design basic wind speeds at Akashi Channel as an example . A series of simulated annually maximum wind speeds was represented as the double exponential distribution, and the expected wind speeds at this site were estimated as 44, 47, and 50 m/sec for the 50, 100, and 200 year return periods, respectively.

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Aerodynamics plays an important role inimproving automobile fuel econonw and vehicular motion, and wind tunnel tests are performedwith high frequency to quantitatively evaluate the aerodynamic characteristics of automobiles.
This review describes the trendof the aerodynamic dragreduction with tiThe correlation testsof the full-scale wind ttmnelsand the coast-dorm testsinwindyme.environments are discussed in order to predict correctly the aerodynamic drag coefficients. The recent research work on cross-vdnd hazards to automobiles, especially cross-wind characteristics and dynamic behavior of automobiles, are also reviewed.
With the rent increaseincomputer speed and capacity, computational fluid dynamics, developed mainlyecin thefieldsofaeronautical and aerospace engineerings, is gradually finding applications inaerodynamics. Several examples of computer simulations by the panel method and the k-ε.automotiveturbulence model are shown for the complex flow around a vehicle.

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A discrete vortex approximation which combines the vortex shedding model with the singularity method is developed for the analysis of unsteady separated flow past a bluff body. In this method. the flow past the body is assumed to be a potential flow except in the region of free shear layers which shed downstream from the separation points. Then the free shear layers are approximated by discrete vortices and the body is represented by vorticity distributions. This method can be easily applied to bluff bodies of complicated shapes. The method is applied to the calculations of the flow concerned with the wind engineering. The calculated results are compared with experiments and a good agreement is shown.

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The paper commentsonthe present state of wind-induced flutter problemsof various structures. These areseparatedflowflutters such as galloping and torsionalflutter, includingvortexexcitation, andcoupledflutter. Eachcontains elements ofself-excitation, or the effect ofadditional force induced by motion. In the first, the difference of onset of flutter is described in the senseof negative damping effect for separated-flow bluff bodies and coupling phase lag effect between different freedoms. The separatedflow flutter instabilities, associated with a distinctive and irreversibleevolution of separation andeattachment of flowaswindspeedincreasesand amplituderof motion diverges, are explained byusing of measured unsteady aerodynamicpressure distribution. The effect of wind turbulence and the quasi-steady theory applicability are also reviewed. Theomplex eigen valueanalysis forcoupled flutterin- stability of 3-dimensionalframe work structural systemsis discussed and compared with theconventional method fora two-degrees-of-freedom rigid body system. Finally, the gust response isemphasized for the proposed twin bridge due to a new designconcepttocombat coupled instability for large span suspended bridges.

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The number and size of construction works overseas is increasing, including high-rise buildings and other large structures. Since unlike Japan most foreign countries have no problems with earthquakes, wind load is considered as an important external force for design. Therefore when a Japanese company has concluded a contract for construction abroad, there are sometimes problems in calculating wind load. This is often caused by lack of knowledge regarding the codes of practice of the country or a difference in opnion between local consultants.
The following report gives an outline of foreign wind loading codes, and problems concerning their application based on previous experiences of the writer.

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The problems of the wind pressure measurements can beattributed to little knowledge of the characteristics of the actual wind pressures. The difference to a ordinal wind tunnel test arises mainly from the discrepancy of Reynolds number and the unsteadiness in anaturalwind flow.On the point ofwily the example of themeasuredpressure data of a hotel building is presented to discuss taesimilarity. By ascale analization a quasi-steadiness is possibly found out for the scale length fit to the building size. The suction on the side wall is more weekend under the steadiness condition than that of a wind tunnel test.

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