Gupta, Nishant (2015-08). A Study of a Plug to Counter Wind Forces. Master's Thesis. Thesis uri icon

abstract

  • The wind loads are one of the greatest environmental threats that exist for a building. Coastal areas close to the equator are especially prone to damage caused by cyclonic wind loads. Historical data shows that there has been a long history of cyclonic activities causing devastating damage to life and property. The legendary storm that saved Japan from invasion about a millennia ago is one such example. Recent cyclones, such as Typhoon Tip in 1979 and Cyclone Tracy in 1974, have been responsible for causing billions of dollars' worth damage and killing a significant number of people. The maximum gust speed recorded to date, over 200 mph, is capable of destroying a building. Various building codes and regulations are based on international research that covers the design of buildings for high winds. At higher wind speeds, as seen in cases of cyclones and tornedoes, the external pressure on the buildings shell increases as the square of the wind speed. One of the failure modes for buildings is a catastrophic failure of the window elements in a high-pressure windstorm. The failure creates a resonance, named after Herrmann von Helmholtz, that overloads the roof and walls from the wind pressure and the mass movement of air. A new device was developed in this research to smoothen the transition from a closed to open state for a buildings opening. The device has a controlled failure of a plug element. The purpose of the research was to develop a test arrangement to generate cyclonic wind pressures inside a box container to test failure load for the plug. The results show that a plug with a friction joint between the pipe could be used to control the flow of air from the exterior to the interior of a room at a pre-determined pressure inside the box. The system was found to work and able to create a low level of damping to model the Helmholtz resonator. Further research is recommended using different plug samples.
  • The wind loads are one of the greatest environmental threats that exist for a building. Coastal areas close to the equator are especially prone to damage caused by cyclonic wind loads. Historical data shows that there has been a long history of cyclonic activities causing devastating damage to life and property. The legendary storm that saved Japan from invasion about a millennia ago is one such example.

    Recent cyclones, such as Typhoon Tip in 1979 and Cyclone Tracy in 1974, have been responsible for causing billions of dollars' worth damage and killing a significant number of people. The maximum gust speed recorded to date, over 200 mph, is capable of destroying a building.

    Various building codes and regulations are based on international research that covers the design of buildings for high winds. At higher wind speeds, as seen in cases of cyclones and tornedoes, the external pressure on the buildings shell increases as the square of the wind speed. One of the failure modes for buildings is a catastrophic failure of the window elements in a high-pressure windstorm. The failure creates a resonance, named after Herrmann von Helmholtz, that overloads the roof and walls from the wind pressure and the mass movement of air.

    A new device was developed in this research to smoothen the transition from a closed to open state for a buildings opening. The device has a controlled failure of a plug element. The purpose of the research was to develop a test arrangement to generate cyclonic wind pressures inside a box container to test failure load for the plug. The results show that a plug with a friction joint between the pipe could be used to control the flow of air from the exterior to the interior of a room at a pre-determined pressure inside the box. The system was found to work and able to create a low level of damping to model the Helmholtz resonator. Further research is recommended using different plug samples.

publication date

  • August 2015