To use the stochastic typhoon model is a powerful tool to estimate the probability of annual maximum wind speed for a long range at a specific site. One can use either a Monte Carlo simulation or a probabilistic procedure. Both methods must yield to the same goal. A simulated example up to the return period of 10000 years at the strait of Akashi is reanalized by a probabilistic procedure. There is a disagreement point in the effect of typhoon speed though the results are nearly same. Observed annual maximum wind speed distributions for 40 years due to typhoons are also investigated to find the effect of super -gradient wind expected in typhoons. There is no significant effect.

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Several systems to analyze 3-dimensionally the data of wind stream flowing close enough over the surface of the ground utilizing photographs have now been under project with us.
In the previous paper, 2 cigar-shaped kite balloons upon which 35mm still-cameras are installed respectively with an aim of stereophotographing another balloon wich is released into air as a tracer are dealt with. With the aid of these ballons, a system to analyze 3-dimensionally the paths of particle of the tracer ballon has been constructed.
In this paper, description is made with adoption of a system developed for stereophotographing the balloons that has been released in air as a tracer by manually settling 4 35mm stillcameras with wich simultaneous operation is possible on the ground surrounding the observational area, instead of the kite balloons.
In parallel with the above trial, a system allowing the paths of particle of balloons to be measured 3- dimensionally only with a single leaf of photographs has been developed.
The said 2 systems has been intended to be applied to observation of the paths of partical of wind stream flowing over mountainous regions.
Resultes effective enough for the survey have been brought about from the above investingation. Especially with the system allowing only a single leaf of photographs to be measured, it is explaind that tracing of balloons or operation of equipment and apparatus is considerably easy and the system is quite an effective tool for observation of wind.

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This paper describes wind tunnel tests of the aerostatic force acting on rooftiles. Pressure distribution acting on full-sized model of rooftiles was measured. The rooftileswere set up on the gable roof of 5.1m wide ×3.2m deep ×2.0m tall in the wind tunnel. The pressure acting on the underside of the tiles, which was found to be both positive and negative due to the wind direction and the location of the rooftile, was effected by 1) gap between rooftile and sheathing board at the eaves, and 2) gap between the neighboring rooftiles.
The authors assumed some model of pressure spreading underside the rooftiles, and caliculated the wind speed at which the dynamic equilibrium of roof tiles was losed.
Compared with the wind speed at which the rooftiles scatter4], the wind speed was found to be lower about 30 %, but the pattern was similar to scattering.

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In order to provide the useful information for designing a wind turbine system in the area of cold Katabatic climate in Antarctica, analyzed were the wind data acquired at the 10m level during the course of operation for five years from 1987 to 1991 by Japan Meteorological Agency and National Institute of Polar Research, and measured continuously for the certain periods of hours in 1991 by the anemometer on top of the 6m tower next to the small wind turbine system at Asuka Observation Camp in Antarctica. Several findings were drawn based on the analysis of data. The duration time of the wind velocity specifically more than 10m/s in the direction of ESE lasted extremely long throughout a year. Gust factors kept almost constant in the range over the velocity of 8m/s. Power spectra have a peak value at 0.052Hz and were well approximated by the equation expressed under the condition of the neutral stratification.

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Wind - induced internal pressures which are relevant to wind loads on cladding were investigated. Wind loads on cladding are said to be estimated as the difference between external wind pressure and internal pressure on the cladding. It is not actually so simple, in case that the pressures vary in time. The fluctuation components of the pressures are taken into the consideration in examining the evaluation method. As the results, the new formula for the gust response factor of internal pressure is derived.
The dynamic pressure transition characteristics of opening are checked by the method of Saathoff, et al. The evaluation method of rms internal pressure based on the idea of pneumatic averaging manifold system is proposed. Applying the method to 7 building models with and without dominant openings in their external walls, internal gust response factors are calculated. The ratio of the areas of dominant openings to gross area for the wall in cases with dominant walls is varied on the calculation. Products of internal pressure coefficient and gust response factor of internal pressure of the building models are also calculated. By summarizing the results, values of products of internal pressure coefficients and gust response factors on cladding design are proposed.

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A new type of transmission tower was built. The tower has a relatively slim body with single waren trusses and solid web brackets, for harmonizing it with the landscape of an urban area.
There is no available data of wind load on such a bracket. A slim body and solid web brackets gave some fear about aerodynamic responses of the tower. A static force measurmeut and an areodynamic test were carried out. The test results gave a pressure force and a pressure moment on the brackets. No self excited oscillation was observed on the bracket model and the tower model.

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Guangdong Building Aerodynamics Wind Tunnel CGB-l built in 1986 is the first large wind tunnel specially designed for architectural aerodynamics in china, supported by State Department of Construction and local government. As an adiabatic atmospheric boundary layer wind tunnel, it is dual test section in tandem and close circuit type. The lager test section is close type of 3m (W) ×2m (H) × 10m (L) and maximum wind speed 18m/s, and small one is either close or open type available of 1.2m (W) × 1.8m (H) × 10m (L) and maximum wind speed 46m/s. Using “spires, roughness elements and barries” simulation methods. the modeled atmospheric boundary layers over various terrains can be generated in either test section at a scale appropriate to the model. On-line digital data acquisition, processing and display have been realized with personal computer-base system.
Testing capacities provided in CGB-1 include pressure and balance measurements, pedestrian-level wind environment investigations, and wind-induced dynamic response with aeroelastic models. Newly-equiped High-Frequency Base Balance has been successfully demonstrated in CAARC standard model testing, resulting in well-agreeded results with other labs in the world.
The vital activities on wind engineering research in this facility since 1986 when the wind tunnel was put into operation, particularly its important role in wind-resistance structure design for many new high rise buildings, long-span cable bridges and shell roof structure, which recently increasingly appeared in Guangzhou, Shenzhen and Zhuhai Economic Special Zone and other South-China modern cities which already became the forward economical developing regions located in typhoon zone. The testing capacity of this wind tunnel is demonstrated here by several typical examples among over 40 major consultant contracts, which have been completed up to date, e.g. Guangdong International Building (63 stories), Shenzhen Xianchen Building (218ni high), Zhuhai Jinniu Plaza (193. 8m high) and so on. It enjoys good reputation through the research projects from the clients.
The wind tunnel CGB-1 is well-equipped, has advanced-trained engineers and good engineering experiences through the testings practice for many years. We sincerely welcome the colleagues both at home and abroad to joint our co-operative research programme and carry out the wind engineering activities there in order to make great contributions to the development of architectural aerodynamics in this country. The wind tunnel lab is ready to serve any customes including in Asia-Pacific area.

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