INFLUENCE OF NON-STATIONARITY OF WIND DIRECTION ON WIND-INDUCED RESPONSE AND PRESSURE OF A SQUARE PRISM BUILDING : A consideration based on the comparison of wind-tunnel tests with field measurements

A hill with a lattice transmission tower presents complex wind field characteristics. The commonly used computational fluid dynamics (CFD) simulations are difficult to analyze the wind resistance and dynamic responses of the transmission tower due to structural complexity. In this study, wind tunnel tests and numerical simulations are conducted to analyze the wind field of the hill and the dynamic responses of the transmission tower built on it. The hill models with different slopes are investigated by wind tunnel tests to measure the wind field characteristics, such as mean speed and turbulence intensity. The study shows that the existence of a transmission tower reduces the wind speed on the leeward slope significantly but has little effect on the windward slope. To study the dynamic behavior of the transmission tower, a hybrid analysis procedure is used by introducing the measured experimental wind information to the finite element tower model established using ANSYS. The effects of hill slope on the maximum displacement response of the tower are studied. The results show that the maximum value of the response is the largest when the hill slope is 25° compared to those when hill slope is 15° and 35°. The results extend the knowledge concerning wind tunnel tests on hills of different terrain and provide a comprehensive understanding of the interactive effects between the hill and existing transmission tower regarding to the wind field characteristics and structural dynamic responses.

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Wind tunnel tests of inter-flat pollutant transmission characteristics in a rectangular multi-storey residential building, part A: Effect of wind direction

Building and Environment ◽

10.1016/j.buildenv.2016.08.032 ◽

2016 ◽

Vol 108 ◽

pp. 159-170 ◽

Cited By ~ 18

Author(s):

Di Mu ◽

Naiping Gao ◽

Tong Zhu

Keyword(s):

Wind Tunnel ◽

Wind Direction ◽

Residential Building ◽

Transmission Characteristics ◽

Wind Tunnel Tests

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Wind-induced response of light and slender arched structures in twin arrangement: Wind tunnel tests and full-scale monitoring

Engineering Structures ◽

10.1016/j.engstruct.2019.04.029 ◽

2019 ◽

Vol 190 ◽

pp. 262-275 ◽

Cited By ~ 1

Author(s):

Sara Muggiasca ◽

Ilmas Bayati ◽

Stefano Giappino ◽

Lorenzo Rosa ◽

Marco Belloli

Keyword(s):

Wind Tunnel ◽

Full Scale ◽

Induced Response ◽

Wind Tunnel Tests

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Effect of Added Mass on Wind-Induced Vibration of a Circular Flat Membrane by Wind Tunnel Tests

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455418501560 ◽

2018 ◽

Vol 18 (12) ◽

pp. 1850156

Author(s):

Yi Zhou ◽

Yuanqi Li ◽

Akihito Yoshida

Keyword(s):

Wind Tunnel ◽

Dynamic Analysis ◽

Pressure Distribution ◽

Added Mass ◽

Wind Pressure ◽

Induced Response ◽

Wind Tunnel Tests ◽

Rigid Model ◽

Flat Membrane ◽

Wind Induced Vibration

Flexible roof structures, such as membranes, are sensitive to wind action due to their flexibility and light weight. Previously, the effect of added mass on the vibration frequency of membrane structures has been experimentally tested. However, the effect of added mass on wind-induced vibration remains unclear. The purpose of this paper is to investigate the effect of added mass on the wind-induced vibration of a circular flat membrane based on wind tunnel tests. First, wind tunnel tests were conducted to obtain wind pressure distribution from the rigid model and wind-induced vibration from the aeroelastic model of a circular flat membrane. Secondly, a dynamic finite element analysis for the proposed added mass model was conducted to obtain the wind-induced vibration of the membrane structure. Then, with the wind pressure distribution obtained from the rigid model tests, dynamic analysis was conducted either with or without consideration of the effect of added mass. According to the dynamic analysis results and the wind tunnel test results, it is clear that considering the effect of added mass in dynamic analysis can significantly improve the accuracy of a wind-induced response. Such an effect is more significant at the windward than the central zone. The inclusion of added mass can result in a larger displacement response as wind velocity increases but a smaller response as the prestress level increases.

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Field Measurements of Dynamic Characteristics and Wind-Induced Response of a Large-Span Roof Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.5349 ◽

2011 ◽

Vol 243-249 ◽

pp. 5349-5355 ◽

Cited By ~ 1

Author(s):

Ji Yang Fu ◽

An Xu ◽

Jiu Rong Wu

Keyword(s):

Wind Tunnel ◽

Dynamic Characteristics ◽

Wind Tunnel Test ◽

Field Measurements ◽

Mode Shapes ◽

Induced Response ◽

Test Results ◽

Large Span ◽

Stochastic Subspace Identification ◽

Roof Structure

This paper presents some selected results obtained from the field measurements of wind effects on Guangzhou International Sports Arena (GISA) during the passage of Typhoon Fanapi in September, 2010. The field data such as wind speed, wind direction and acceleration responses, etc., were simultaneously and continuously recorded during the typhoon. The measured acceleration data are analyzed to obtain the information on dynamic characteristics and wind-induced response of the large-span roof structure. The first four natural frequencies and vibration mode shapes of the roof are identified on the basis of the field measurements using the stochastic subspace identification (SSI) method and comparisons with those calculated from the computational model of the roof are made. The damping ratios of the roof are also identified by the SSI method and compared with those estimated by the random decrement method, and the amplitude-dependent damping characteristics are presented and discussed. Furthermore, the field measurement results are compared with the wind tunnel test results to examine the accuracy of the model test results and the adequacy of the techniques used in wind tunnel tests.

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Vortex-induced vibration of a truss girder with high vertical stabilizers

Advances in Structural Engineering ◽

10.1177/1369433218778656 ◽

2018 ◽

Vol 22 (4) ◽

pp. 948-959 ◽

Cited By ~ 1

Author(s):

Haojun Tang ◽

KM Shum ◽

Qiyu Tao ◽

Jinsong Jiang

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Tunnel ◽

Vortex Shedding ◽

Windward Side ◽

Induced Response ◽

Vortex Induced Vibration ◽

Wind Tunnel Tests ◽

Computational Fluid Dynamics Simulations ◽

Dynamics Simulations

To improve the flutter stability of a long-span suspension bridge with steel truss stiffening girder, two vertical stabilizers of which the total height reaches to approximately 2.9 m were planned to install on the deck. As the optimized girder presents the characteristics of a bluff body more, its vortex-induced vibration needs to be studied in detail. In this article, computational fluid dynamics simulations and wind tunnel tests are carried out. The vortex-shedding performance of the optimized girder is analyzed and the corresponding aerodynamic mechanism is discussed. Then, the static aerodynamic coefficients and the dynamic vortex-induced response of the bridge are tested by sectional models. The results show that the vertical stabilizers could make the incoming flow separate and induce strong vortex-shedding behind them, but this effect is weakened by the chord member on the windward side of the lower stabilizer. As the vortex-shedding performance of the optimized girder is mainly affected by truss members whose position relationships change along the bridge span, the vortex shed from the girder can hardly have a uniform frequency so the possibility of vortex-induced vibration of the bridge is low. The data obtained by wind tunnel tests verify the results by computational fluid dynamics simulations.

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Wind Tunnel Tests and Numerical Simulations of Wind-Induced Snow Drift in an Open Stadium and Gymnasium

Advances in Civil Engineering ◽

10.1155/2020/8840759 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Xintong Jiang ◽

Zhixiang Yin ◽

Hanbo Cui

Keyword(s):

Wind Tunnel ◽

Numerical Simulations ◽

Wind Direction ◽

Interference Effect ◽

Mutual Interference ◽

Wind Tunnel Tests ◽

Direction Angle ◽

Long Span ◽

Snow Drift ◽

Snow Distribution

A long-span sports centre generally comprises multiple stadiums and gymnasiums, for which mutual interference effects of wind-induced snow motion are not explicitly included in the specifications of various countries. This problem is addressed herein by performing wind tunnel tests and numerical simulations to investigate the snow distribution and mutual interference effect on the roofs of long-span stadiums and gymnasiums. The wind tunnel tests were used to analyse the influences of the opening direction (0°, 90°, 180°, and 270°) and spacing (0.3 L, 0.5 L, 1 L, 1.5 L, 2 L, and 2.5 L, where L is the gymnasium span) of the stadium and gymnasium. The wind tunnel tests and numerical simulations were used to analyse the influence of the wind direction angle (from 0° to 315°, there are a total of eight groups in 45° intervals). The following results were obtained. The stadium opening had a significant effect on the snow distribution on the surface of the two structures. An even snow distribution was obtained when the stadium opened directly facing the gymnasium, which corresponded to the safest condition for the structures’ surfaces. As the spacing between the buildings increased, the interference effect between the two structures was reduced. The interference was negligible for a spacing of 2 L. The stadium had the most significant amplification interference effect on the gymnasium for a wind direction angle of 45°, which was extremely unfavourable to the safety of the structure. The most favourable wind direction angle was 270°, where there were both amplification interference and blockage interference.

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Aeroelastic Vibration of Super-Tall Buildings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1025-1026.914 ◽

2014 ◽

Vol 1025-1026 ◽

pp. 914-917

Author(s):

Yong Chul Kim ◽

Sung Won Yoon

Keyword(s):

Magnetic Field ◽

Wind Tunnel ◽

Wind Direction ◽

Natural Frequencies ◽

Tall Buildings ◽

Spring Stiffness ◽

Wind Tunnel Tests ◽

Test Models ◽

Tip Displacement

Aeroelastic wind tunnel tests were conducted on conventional and tapered super-tall buildings to investigate the effect of the taper on the aeroelastic behavior for various wind directions and normalized velocities, with a focus on the maximum tip displacement. The natural frequencies and damping ratios were adjusted by means of the spring stiffness and magnetic field at the bottom of the test models. The displacements at the bottom of the test models were measured and transformed to tip displacements. The results showed that the taper suppressed the maximum tip displacement in both the X and Y directions, although the suppression was greater in the Y direction, especially for small wind directions. Moreover, the variations of the maximum tip displacement in the X direction with the wind direction and normalized velocity were small.

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