Wind characteristics at bridge site in a deep-cutting gorge by wind tunnel test

This paper investigates the effect of a wind barrier on the aerodynamic performance of a train–bridge system under crosswind using a numerical simulation method. The studied bridge is a long-span c...

Effect of wind barriers on the flow field and aerodynamic forces of a train–bridge system:

Advances in wind tunnel experimental investigations of train–bridge systems

With the increase of the running speed of the high-speed train (HST), aerodynamic interference between the HST and surrounding structures becomes more and more important. Traditional wind tunnel ex...

https://www.tandfonline.com/doi/pdf/10.1080/19942060.2020.1832920

Numerical investigation on the crosswind effects on a train running on a bridge

With the development of long-span flexible bridges and the increase of highway transportation, both the dynamic responses of highway bridges under high-speed and heavy vehicles and the safety control of vehicles have deserved general concerns. First, this paper briefly discussed some researches on coupling vibration of vehicle and highway-bridges, then roundly summarized main research achievements accounting on the vehicle analytical model, bridge analytical model, surface roughness of road, numerical method of vehicle-bridge coupling vibration and some other aspects. Meanwhile, some research trends and challenge on vehicle and bridge dynamic interaction in engineering application were pointed out.

Development and Challenge of the Vehicle and Highway Bridges Dynamic Interaction

In order to investigate the simulation method of a scale model for a porous wind screen, the aerodynamic coefficients of vehicles under the action of a wind screen installed on the railway bridges are measured by wind tunnel tests The wind screen is 205m high, with the porosity of 30%, and with different hole shapes The effects of hole size and hole shape are analyzed, and the similarity between the wind screen with circular holes and the wind screen with longitudinal bars are discussed The result shows that the circular hole size of a wind screen at the scale of 1∶20 should be in the range of 8mm to 12mm; the hole shape of a wind screen with the same porosity has some certain effect on the aerodynamic coefficients of the windward vehicle; the longitudinal bar wind screen with more than 10 gaps is equivalent to a wind screen with the circular hole size of 8mm The results could provide some references for the wind tunnel test and numerical simulation of a wind screen

Simulation method of porous wind screen scale model on bridge by wind tunnel tests

In order to evaluate the wind shielding effect of wind barrier for railway bridges,aerodynamic coefficients of a train and two trains passing each other on a railway bridge installed wind barrier with different heights were measured by wind tunnel tests.On the basis of the test results,it was put forward that the aerodynamic coefficients of a train can be used to assess the effect of sudden change of vehicle wind load,and the magnitudes of sudden change of vehicle wind load at different tracks can be considered as the evaluation index.Moreover,the DEA(data envelopment analysis) method was adopted to evaluate the wind shielding effect of wind barrier.The research result shows that the DEA method is feasible to evaluate the wind shielding effect of wind barrier for railway bridges,and the preferable height of wind barrier is 1.72 m.

DEA-Based Evaluation of Wind Shielding Effect of Wind Barrier for Railway Bridges

An analysis was carried out for flow characteristics around a vehicle-bridge system consisting of German ICE(intercity-express) vehicle and standard simplysupported bridge under cross wind.Based on the two-dimensional Reynolds averaged incompressible Navier-Stokes equations,the RNG(renormalization group) turbulence model was used in the numerical simulation.Triangular grid and quadrilateral grid were used to divide the computational domain,the finite volume method was adopted to discretize the governing differential equations,and the pressure-velocity field was coupled using the SIMPLE(semi-implicit method for pressure-linked equations) algorithm.Furthermore,the research results of driven cavity flows were applied to the analysis of flow characteristics around the vehicle-bridge system considering the wind-break wall effect.The analysis shows that the wind-break wall of a high-speed railway bridge has the similar vortex characteristics of driven cavity flows in preventing wind.

Analysis of Flow Characteristics around High-Speed Railway Bridge-Vehicle System under Cross Wind

To consider the difference of wind characteristics for different members of a long-span bridge in complex terrains,the basic wind speed for the region was calculated on the basis of the statistical analysis of historical observation records of wind speed from meteorological stations involvedFrom the simultaneous observation data from the meteorological stations and observation points in a bridge site,the revision relationship between wind speeds at the bridge site and at the meteorological stations was established by the analysis of correlativityBy considering the terrain feature of the bridge site and combining the results of computational fluid dynamics analysis,the design wind speeds were determined for bridge deck and each pylon,and the concept of integrated wind speed standard was presentedThe results show that the integrated wind speed standard instead of the uniform wind speed standard takes the differences among wind characteristics for bridge deck and each pylon into account,and it is fit for long-span bridges over a deep-cutting gorge

Integrated Wind Speed Standard for Long-Span Bridges over Deep-Cutting Gorge

Strong wind not only controls the design of long span bridges,but also directly affects the traffic safety of vehicles on the bridges.Based on the coupled vibration analysis of a wind-road vehicles-bridge system,the wind-induced vehicle accident analysis is improved,since the probability of a statistical method was adopted in the criterion of vehicles side-lurch accidents and side slipping accidents.In the case study,the dynamic response of a bridge under strong wind was investigated,and the safety operation of vehicles was evaluated.The traffic critical wind speed of side-lurch and side-slipping for the moving vehicles at dry,wet,snow,ice road conditions were calculated,respectively.Accordingly,the vehicle speed limit at strong wind conditions is proposed for the management of traffic safety,.

Liao Hai-li

Papers

Simulation method of porous wind screen scale model on bridge by wind tunnel tests

DEA-Based Evaluation of Wind Shielding Effect of Wind Barrier for Railway Bridges

Analysis of Flow Characteristics around High-Speed Railway Bridge-Vehicle System under Cross Wind

Integrated Wind Speed Standard for Long-Span Bridges over Deep-Cutting Gorge

Wind-vehicle-bridge system coupling vibration and traffic safety analysis