The University of Western Ontario Wind Tunnel Labs received $9m grant funding to build a new facility for testing the effects of hurricane wind loads on full-sized houses. The objective was to update building codes to improve survivability of domestic structures in extreme weather conditions. They needed a novel wind load generation system that accurately reproduced the pressure patterns experienced in up to 200mph winds.
We developed a novel pressure loading actuator (PLA) system based on an existing 5-port valve concept to provide continuously variable positive and negative air pressure into various sizes of pressure box. This involved:
- Selecting and sizing key components including large, closed-circuit air pumps, servo motors and control units
- Developing a 5-port valve, optimised for efficient air flow and linear control characteristics
- Designing control algorithms for accurate reproduction of the desired pressure profiles
- Design of control electronics to UL standards
- Build and test of first article units
- Transfer of the design to the university’s manufacturing partner
- On-site support to system commissioning
The university built 100 PLA units and installed them in its test facility in London, Ontario. It has now completed testing of two different house designs and found many areas of improvement to building standards. The facility extends its existing capability by enabling full-scale reproduction of wind loads measured in its wind tunnels on scale models. It has further expanded the use of the facility for testing large building panels and panes of glass.
This new capability, dubbed ‘Three Little Pigs’, continues to provide building improvements that reduce the level of destruction caused by extreme weather events.