Wind Loads on Structures

Research Areas:

  • Influence of simulation methods on wind load characteristic and design load coefficients. As for the simulation two methods are considered; wind tunnel testing and computational fluid dynamics.

  • Response of high-rise buildings to wind loading. Comparison of response based on wind tunnel tests to full-scale with focus on response characteristic and relevance to human comfort.

  • Aerodynamic loads on iced bridge cables. The change of the cross-sectional shape under icing influences the aerodynamic loads. The static and dynamic response of iced cables is investigated in a specifically-built Climatic Wind Tunnel.

Aerodynamic loads on iced bridge cables. The change of the cross-sectional shape under icing influences the aerodynamic loads. The static and dynamic response of iced cables is investigated in a specifically-built Climatic Wind Tunnel.

The load process wind imposes on a structure depends on the shape and flexibility of the structure and of the air flow characteristics. Many factors play a significant role and make the loading of even standard buildings unique to each another due to different urban or terrain context. 

Visualisation of turbulent flow field around a low-rise building

Interpretation of flow field around low-rise building

At top: visualisation of the airflow over a low-rise building with helium-filled soap bubbles.
Below: main flow features with characteristic points regarding surface pressure.
SP = stagnation point, SL = separation at leading edge, RP = reattachment point, ST = separation at trailing edge
 

The distribution of the wind pressure over the building envelope or on structural elements and its variation in time are the key parameters determining the magnitude and characteristic of the response. For structural design peak loadings are of main interest. The peaks may be limited to local areas (for example cladding elements, windows and roof tiles) or to global loading of the entire structure. To obtain structural safety the simulated peak loadings are transformed to characteristic load fulfilling certain requirements regarding the overload risk. Traditionally investigated in wind tunnel tests the alternative of numerical simulation using CFD becomes with increasing computational power and advancing commercial software more and more attractive for consultancy and design engineers. In our research on Computational Wind Engineering we focus on applying the available methods in a way that we get results of similar quality – or even better – as we get from classical wind tunnel tests.