Wind Loading of Buildings and Structures
Strong winds can generate large loads on tall buildings and slender structures, often triggering dynamic responses. For this reason, wind loading is generally considered to be one of the most important factors when designing tall structures. Because of the complex interaction of turbulent wind flows and the flexibility of structures, wind loading on buildings can only be measured accurately by wind tunnel testing.
At GWE, we create scaled model replicas of study sites and their surroundings, typically at a scale of 1:400, place them in the wind tunnel, and perform tests for the full 360O azimuth of wind directions. Then, we combine the raw data with statistical models of the wind climate for the building’s location to predict wind loads and building accelerations. At GWE, we have experienced engineers and technicians who are capable of accomplishing project goals quickly and efficiently using our in-house testing and fabrication facilities.
Our studies are conducted using either the high-frequency force-balance (HFFB) technique or the high-frequency pressure-integration (HFPI) technique, which provide the loading and deformation information necessary to design safe structures. As well, GWE staff has experience with more complex aeroelastic modelling for unique situations.
Next to wind loading, occupant comfort and functionality of buildings are the next most important priorities in tall building design. Adequate serviceability of a building is assured by controlling accelerations at top occupied floors related to occupant comfort and building deflection (inter-storey drifts) related to interaction of building components.
Building motions increase under stronger wind, but decrease when a building becomes stiffer or has more inherent damping. Besides these factors, good aerodynamic design of tall buildings can avoid the largest resonant vibrations by detuning the natural vibration of the building from the vortex shedding around the building corners for prominent wind speeds.
When detuning by structural stiffening or geometric modification are not feasible or economical, the problematic vibrations can be mitigated by introducing supplemental damping such as Tuned Liquid Sloshing Dampers or Tuned Liquid Column Dampers, among other options. Information relating to building motions and accelerations are also derived from wind tunnel testing using the HFFB and HFPI approaches. GWE engineers routinely interact with the design team members to provide advice for the most economical solutions to building motion and wind loading problems