Field measurement study of wind characteristics in mountain terrain: Focusing on sudden intense winds.

Due to the local terrain and temperature, various types of intense wind, such as sudden intense winds, thermally developed winds, and thunderstorms, will occur in mountainous areas of different regions and periods of time. The identification and separation of intense wind events into different families are key topics in wind engineering to study the characteristics of intense winds in mountainous areas, which are essential to investigate the wind-excited response of structures. This research presents a systematic field measurement study on intense wind events in a deep-cut canyon situated in a mountainous area of southwestern China and identifies a series of sudden intense wind events whose wind speed, direction, ambient temperature, and other characteristics change rapidly. To distinguish and isolate such events, an automatic classification method was proposed, and 11 sudden intense wind events were captured. Additionally, it was also found that the sudden intense wind had relatively strong nonstationary characteristics. Finally, the average and fluctuating wind characteristics of sudden intense winds were investigated, and the time-variant characteristics were discussed in detail. These varying characteristics at high wind speeds, which will make the loads acting on bridges more complex, should be considered in the wind-resistant design of long-span bridges. • An automatic classification method is proposed for extracting sudden intense winds from long-term field measurement data in mountainous terrain. • A series of wind samples are found interesting with sudden changes in wind speed and temperature drops. • Sudden intense wind is found to have relatively strong nonstationary characteristics. • The regulation of fluctuating wind characteristics changing with time is discussed in detail. [ABSTRACT FROM AUTHOR]