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

Jiang

et al. 2022

Sci Rep

Self Cite

The local wind environment above the bridge deck affects the aerodynamic characteristics of vehicles, thus affecting the driving safety of the bridge deck. Influenced by the mountain topography and the bridge deck's ancillary facilities, the local wind environment above the bridge deck is complex and changeable, and its impact on the bridge deck traffic can not be ignored. In order to accurately evaluate the local wind field parameters, a monitoring system of the local wind environment is developed. Utilizing the monitoring system, wind parameters above the approach deck of a long-span suspension bridge in a mountain area are measured. The relationship of wind characteristics between the incoming flow and the wind above the bridge deck is investigated. Results show the significant difference between the local wind environment above the bridge deck and the incoming flow's characteristics; the wind profile above the bridge deck does not follow the exponential distribution; the equivalent height of the wind load on the vehicle is higher than the vehicle's gravity centre. This study is relevant for studying the local wind environment, driving safety, and serviceability of long-span bridges in mountainous areas.

Section: Theory and Methodologysupporting

confidence: 88%

Field measurement of local wind environment on the approach deck of a suspension bridge in mountain terrain

Jiang

et al. 2022

Sci Rep

Self Cite

“…These wind field characteristics play a crucial role during the construction and operation phases of bridge engineering, and influence the sustainable design of bridges [7]. Currently, researchers have extensively studied these phenomena, making many significant contributions based on their field measurements [8][9][10][11], wind tunnel tests [12][13][14][15], and numerical simulations [16][17][18][19].…”

Section: Introductionmentioning

confidence: 99%

Analysis of Wind Field Characteristics of Ideal V-Shaped and U-Shaped Canyons

Zhou

Xin

Yu³

et al. 2023

Sustainability

As an important part of road transportation, bridge engineering plays a pivotal role in infrastructure construction. The wind field characteristics of the bridge site area have an essential influence on both the construction and operation period of the bridge, especially in mountainous canyon terrain. In this paper, a numerical simulation using computational fluid dynamics software was conducted to examine the intricate wind field characteristics in mountainous regions. The study focused on ideal V-shaped and U-shaped canyons, aiming to investigate the influence of various parameters. These parameters included three distinct heights, seven angles, and seven widths of the canyon. The findings indicate that in both ideal V-shaped and U-shaped canyons, the canyon acceleration effect weakens as the angles or widths of the canyon increase. The wind speed amplification effect gradually disappears when the V-shaped canyon angle exceeds 160° or when the U-shaped canyon has a width-to-height ratio of approximately 5:1. The wind speed amplification effect strengthens as the canyon height increases. The wind speed acceleration effect exhibits a linear relationship with the angle of the V-shaped canyon, while it demonstrates a logarithmic relationship with the width of the U-shaped canyon. Additionally, the wind speed amplification factor follows a logarithmic distribution along the canyon height. The wind field characteristics observed in this study offer valuable insights for future bridge designs in mountainous regions featuring V-shaped and U-shaped canyons.

“…Under these assumptions, current structural wind resistance codes and standards do not take into account non-stationarity [9,10]. However, recent studies have shown that significant time-varying features are observed in strong winds, including not only mean wind velocity [11] but also turbulence intensity, and turbulence integral scale [12][13][14][15]. Conventional stationary model will overestimate the turbulent wind parameters of strong winds [16].…”

Section: Introductionmentioning

confidence: 99%

“…Based on Priestley's theory, Huang et al [24] assumed that the EPSD consists of several stationary power spectra uniformly modulated by superposition, but its accuracy depends on the selected modulation function and stationary power spectrum, and it is difficult to apply [25]. To facilitate understanding and application, Hu et al [26] extended the Kaimal spectrum to EPSD based on its general form and considered the time-dependent fitting parameters, but this model only considers the turbulence integral scale calculated from the height above the ground, which may be less applicable than the Karman spectrum in complex terrain [13,15,27,28]. Scholars have established the Karman spectrum models based on non-stationary turbulence parameters [29,30], but their coefficients are fixed and can hardly reflect the time-and frequency-dependent properties of turbulent wind fields.…”

Section: Introductionmentioning

confidence: 99%

Non-stationary characteristics and evolutionary power spectral density model of strong winds

Hu,

Peng,

Yang

et al. 2023

Preprint

Wind velocity is usually assumed to obey a stationary stochastic process in wind-resistant design, without taking into account the non-stationarity. The wavelet transform (WT) method was adopted to capture the time-varying properties of the low-frequency mean winds, and the associated turbulence features, including turbulent intensity, gust factor, probability density function, and power spectrum, were analyzed in depth. Furthermore, the three-dimensional evolutionary power spectral density (EPSD) of strong winds was estimated. Finally, this study presents a study on the modeling of the three-dimensional EPSD. The results show that the proposed EPSD models are in good agreement with the estimated EPSD. This study can be used for numerical simulation of non-stationary wind and analysis of wind-induced effects under turbulent atmospheric boundary layers with consideration of non-stationarity.