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Across much of the world, wind gust data are continuously measured by Automatic Weather Stations (AWS). However, the meteorological origin of individual extreme gust events within these datasets are seldom automatically assigned. To overcome this, Self-Organizing Maps (SOM) are proposed here as an automated tool to classify gust events within 1-min AWS data. In this paper, this method is specifically used to distinguish between wind gust events of convective (often broadly termed non-synoptic or thunderstorm) and non-convective origin, with the latter events further sub-classified as either, wind only, transition, or other. The efficacy of a range of different SOMs and input variables were assessed, and it was found that those that utilised gust wind speed, temperature, and pressure generally outperformed other models when classifying wind gusts. Applying this approach in the Australian context, all wind gusts of convective origin greater than 70 ​km ​h−1 (19.4 ​m ​s−1) and 90 ​km ​h−1 (25 ​m ​s−1) were identified at 306 AWS across Australia and a climatology of seasonal and annual convective wind gust occurrence developed and discussed.

When a train moves through the air, a region of air moves along with it at approximately the same speed: this region of air is known as the ‘slipstream’. Numerical simulations were conducted in order to simulate the slipstream around a model-scale freight train when subjected to crosswinds with two different yaw angles; 10° and 30°. The results were compared to a previous slipstream study without a crosswind. The velocities on the windward side of the train for each case are mostly lower than the crosswind speed due to the flow stagnation on the side of the train. In general, crosswind velocities are lower than those in the no-crosswind case. On the leeward side, velocities from the 30° crosswind case remain higher than train speed for more than two metres from train side. Peak instantaneous velocities showed strong dependence on yaw angle and position from train side as well as exhibiting superficial comparison to full-scale data. Velocities were used as inputs to a spring-mass-damper model which modelled human responses to wind gusts. The effect of a crosswind on the train's slipstream significantly increased the likelihood of a person becoming unsteadied while standing on the leeward side of the train.

To validate applicability of the novel hybrid meteorological model/engineering LES method to damage estimation of actual tornado events, simulation is performed focusing on the severely damaged area of the strong tornado on May 6, 2012 in the city of Tsukuba with the realistic tornado structure reproduced in the meteorological model, the actual building distribution, and the topography. The flows over the disaster-affected low-rise residential area show an evident converging character at a height close to the rooftops. Intense strong wind bands are formed by the influence of the buildings. The simulated maximum wind gust is compared with the distribution of actual building damage. It reveals that the hybrid method can reasonably estimate distribution of the building damage over the target area in the tornado event. The track nevertheless exhibits building-scale perturbation that may be attributed to chaotic randomness of the tornado behavior on the complex rough surface. Using the simulated aerodynamic force, simplified case studies on the occurrence and process of damage to two individual buildings is also presented.

The new Indian wind loading standard (IS 875 (Part 3), 2015) was brought out after a gap of 28 years. There are several changes especially on the front of calculating wind loading on tall buildings. Among them, one of the noticeable changes is by bringing the equations to calculate along wind gust factors replacing the complex figures from the earlier version of the IS875. Further, the new IS875 instigated across wind provisions for the first time. The earlier versions of the Australian wind loading standard (AS 1170.2, 1989; AS/NZS 1170.2, 2011) were the basis for most of these changes. This paper critically reviews each one of these new updates and reminds the users of the IS875 about potential issues of adopting the current standard as published for determining local pressures on facades as well as overall wind loading on tall buildings. Several amendments are recommended.

The greatest attention to the UK wind climatology has focused upon mean windspeeds, despite a knowledge of gust speeds being essential to a variety of users. This paper goes some way to redressing this imbalance by analysing observed daily maximum gust speeds from a 43-station network over the period 1980–2005. Complementing these data are dynamically downscaled reanalysis data, generated using the PRECIS Regional Climate Modelling system, for the period 1959–2001. Inter-annual variations in both the observed and downscaled reanalysis gust speeds are presented, with a statistically significant (at the 95% confidence interval) 5% increase across the network in daily maximum gust speeds between 1959 and the early 1990s, followed by an apparent decrease. The benefit of incorporating dynamically downscaled reanalysis data is revealed by the fact that the decrease in gust speeds since 1993 may be placed in the context of a very slight increase displayed over the longer 1959–2001 period. Furthermore, the severity of individual windstorm events is considered, with high profile recent events placed into the context of the long term record. A daily cycle is identified from the station observations in the timing of the daily maximum gust speeds, with an afternoon peak occurring between 12:00–15:00, exhibiting spatial and intra-annual variations.

Wind turbine blades are made of fiberglass material to be cost effective, but they can be damaged by moisture absorption, fatigue, wind gusts or lightening strikes. It is important to detect the damage before the blade fails catastrophically which could destroy the entire wind turbine. In this paper, four different algorithms are tested for detecting damage on wind turbine blades. These are the transmittance function, resonant comparison, operational deflection shape, and wave propagation methods. The methods are all based on measuring the vibration response of the blade when it is excited using piezoceramic actuator patches bonded to the blade. The vibration response of the blade is measured using either piezoceramic sensor patches bonded to the blade, or a scanning laser doppler vibrometer. The sensitivity of the techniques to detect a reversible damage simulated by a steel plate clamped to a section of a wind turbine blade is compared in this paper.

To investigate the behavior and effectiveness of viscous-damping (VD) walls in controlling wind-induced vibrations in multi-story buildings, an aeroelastic building model with VD wall units was constructed for the experimental study. Wind tunnel testing of the model included conditions of simulated gust. In addition to being effective in reducing the effects of wind gust in the along-wind direction, the experimental results showed that VD walls were also effective in the cross-wind direction. The damping action of the VD walls in the rotational mode was also investigated.

A computational study has been conducted to evaluate raindrop trajectories, rain intensities and angles of impact of raindrops on various surfaces of a CAARC standard building. In the first stage, the pressure distribution around the building is calculated from a 3-D computational fluid dynamics (CFD) program. The surface mean pressures are then compared with those obtained from a wind tunnel investigation. In the second stage, raindrops of various sizes are introduced into the airstream above and upwind of the building and allowed to hit the building. A Monte-Carlo simulation, based on the computed turbulence timescale, is used to account for turbulent buffeting of raindrops by wind gusts. The resulting rain impact data are presented here.

Dynamic data for reinforced concrete (r.c.) tall chimneys can be evaluated using their vibration measurements in low-speed wind gusts. The paper describes the method and gives examples of its application for some existing r.c. chimneys. Results are presented and discussed.

Background and main features of the most recently endorsed Romanian standard on wind action, STAS 10101/20-90 are presented. Research carried out on summarizing the developments of some reference codes, on zonation of Romania, on the dynamic effects of wind gusts and on structural safety is briefly presented. The most characteristic features of STAS 10101/20-90 are then summarized. Some suggestions on further developments in this field are finally presented.

This paper describes an active simulating procedure of the time history of wind velocity in a wind tunnel. The simulated time histories of the wind velocity by this technique fitted well the target ones. The wind gust observed at the site was simulated. The step changing wind gusts which wind velocity changes in a short time were generated. The simulated time histories of wind velocity were repeatedly reproduced. The advantages of active simulation are summarized.

Measures at present in use in the U.K. to control vehicle movement at exposed sites during windy periods are rather arbitrary and ill defined. This note presents rational methods for such traffic control based on an analytical model developed by the author. A “two level” system of control is proposed with high sided vehicle speed being restricted to 10 m s −1 at a wind gust speed of 17.5 m s −1 and vehicle movement being stopped completely at a windgust speed of 22.5 m s −1 . The analytical model suggests that no account should be taken of wind direction, and also shows that the inter-relation between accident wind speed and vehicle speed and wind direction is far from being straightforward.

Two probabilistic wind load models for cyclonic and non-cyclonic regions of Australia are described. These models have been used in conjunction with dead and live load models to assess the safety indices (β) of structural members designed according to the present Australian standards. New load combination formulae have then been proposed for ultimate limit-states design. Compared with the rules in existing codes, these formulae lead to a more consistent level of safety in the practical range of load combinations. Finally, a change in the return period for nominal wind gust speed from 50 years to 1000 years for the ultimate limit state has been proposed and the reasons for the change are given.

The width of the direction trace produced by a standard (e.g., Dines) anemograph gives rise to considerable uncertainty as to the appropriate direction for given large gusts, and a consequent uncertainty about the expected extreme gusts calculated for particular sectors. Further uncertainty is added when the calculated expected extreme gusts are applied to a fairly wide area around the observing site. The magnitudes of the directional uncertainties are examined for a particular site (East Sale in Victoria, Australia), and an approach to the problem they pose is suggested, through smoothing of the directional gust data. For East Sale such smoothing greatly reduces the irregularity of the sector-to-sector variations in the estimated directional extreme gusts.

The number of days per year on which the wind blew at some time in particular direction sectors (“wind days”) was examined for East Sale in Victoria, and considerable year to year variations were found. The effect of the observed variability on estimations of extreme wind gusts was considered, and it was found that: 1. (i) the conservatism inherent in making extreme gust estimates without taking account of variations in the annual number of wind days could explain the frequently observed anomaly of estimated directional extreme gusts for long return periods being larger than the estimated global gusts; 2. (ii) the largest annual gust was in some sectors correlated inversely with the annual number of wind days, hence, the usual extreme value theory was not applicable; 3. (iii) nevertheless, at East Sale the Gumbel estimation procedure used without allowing for variations in the annual number of wind days gave results in every sector which fitted the observed data well.

The estimation of the probability of extreme wind gusts across railway embankments has become an important requirement in the assessment of the safety of modern lightweight trains. A programme of experimental measurements, both in the field in Cumbria in North-West England and on wind-tunnel terrain models, is described. The results are used to assess a proposed empirical method of gust prediction and as an evaluation of the usefulness of wind-tunnel methods for the simulation of flows over complicated terrain.

For economic design of large structures it would be desirable to have maximum wind gust estimates for each direction sector rather than the global estimates at present available. Current observational practice is to record only a single maximum gust daily, together with its direction sector, for each observing station. These data could be used to make directional estimates of extreme gusts only if no significant gusts from any direction are masked by stronger gusts from other directions on the same day. To obtain an indication of whether such masking occurs, twenty-nine years of anemograph charts for a single station were examined. It was found that masking of important gusts did occur for some direction sectors. The data considered also raised questions related to the uncertainty of extreme gust directions.