Recent hurricanes along our Gulf Coast shores – in particular, Hurricane Katrina – have demonstrated the destructive power extreme winds can have. When video footage of such devastation is seen, the need for advancing technology to aid with pre-fabricated, pre-engineered steel structures in resisting extreme weather is never more clear.
As new developments are made in terms of the effects of high winds on steel structures, new structural regulations are brought into use. The correct structural design for all-steel buildings to withstand extreme winds means that the principle building system components must be reinforced.
In any of the 50 states there normally is a minimal “design wind speed” rating that a pre-fabricated, pre-engineered building must meet. Simulating NOAA guides, the valuation will be figured based on a “three second wind gust” at any given location. The wind measurement is then altered to a measurement that involves velocity pressure which is expressed as a pounds-per-square foot computation. You can look at most any building, therefore, and discern the needed design wind pressure aspects by means of a formula that consists of appropriate readings for the ground surface combined with exposure and height computations of the steel structure.
Research involving high wind damage shows that the breakdown of walls and roofs in any structure commonly occurs at the rooftop eaves and the four corners. These specific areas of the steel building, accordingly, should receive the most amount of engineering attention so that any collateral components in these building sections are stronger in the face of acute winds. These segments of extreme wind loading center on a salient corner approach, which typically pays greater reinforcing and planning analysis to all four corners of a steel structure system.
A metal structure can be weakened by extreme winds in a number of ways. Movement of the entire structure is one complication. This occurs if a metal building actually slides off of its footing as an entire element due to the structure’s bond with its foundation failing. The most catastrophic failure is total collapse. A “house of cards” situation can happen when acute winds trigger the building to totally breakdown upon itself, terminating in absolute destruction of the unit. Damage to building elements refers to a high wind episode in which only a portion of the metal building fails or gives way. This can eventuate in roof failure, doors being blown inward, or sections of the wall shredded. A steel building can also invert as an effect of severe winds. The whole building will topple over due to defects of foundation anchoring. Insufficient weight load can also allow harsh wind events to compromise the building.
When calculating the particular effect of the wind on a steel building, the lateral characteristics of wind flow should not be the only element analyzed. Perpendicular wind measurement is also now involved in any figuring. The continuing research into optimal wind loading in regards to pre-fabricated, pre-engineered steel buildings is constantly progressing, allowing modern buildings to even better resist the effects of extreme weather.
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