New
discoveries are being developed every day to come up with stronger and more
sustainable building materials to use across the country. While these materials are the same in most
buildings, different job sites will threaten the structure with environmental
factors that have to be taken into account.
The National Council of Examiners for Engineering and Surveying (NCEES)
requires that professional engineers be registered to work in their state of
choice because the extensive diversity of the landscape and the different
design standards that follows.
When designing a structure the first
thing taken into consideration is the different loading combinations that
building is based on. How much weight
the structure can hold depends on the type of building and its surroundings. For example, a library has additional support
to hold the weight of books and schools have strict rules for a large population
of students and teachers. This is the same for anything that can cause a
negative impact from the environment. Depending on what part of the country you are
in this could completely change the standards that the structure has to
follow. A standard blueprint can be
heavily affected by the influence of regional impacts such as an excess of snow
in northern states, abundance of wind near the east and west coast, earthquake
activity near fault lines, and a vast diversity of soil types. It did not take
long for standards to develop in state building codes to accommodate the
negative impacts of certain regions, all of which are still being used today.
To accommodate conditions in areas
of severe weather and adverse effects to a structure, several alterations can
aide in reinforcement to prevent partial or whole failure and the possible loss
of human lives. Using a typical Office
building as an example, the design will need to be altered depending on the
severity of the combination of loading that was previously listed. If the structure was built in a colder
climate several design problems need to be addressed. Due to the additional weight of snow,
buildings need to have roofs that can hold additional weight or have a certain
slope to prevent sticking.
Serviceability or the maintenance can also be considered due to the
wearing of the structure from snowstorms or repeated freezing and thawing processes. This may not be a problem in more southern
states, but there the issue of excess wind loads need to be heavily
considered. With lateral bracing a
building can resist the force of the wind and avoid being blown over. With the addition of vibration dampers
seismic activity can be reduced in a much similar fashion in a building near a
fault line. While all of these factors
may only happen in portions of the United States a factor that always has to be
taken into account is the soil type.
Geotechnical Engineers specialize in identifying soil types and
different ways that they react to structures built on them. Having a foundation based on an incorrect
soil type could cause the soil from underneath a building to sink in the ground
or be lifted off the foundation.
No matter where a building is in the
United States, there are going to be strict standards set by the state to
handle unique construction conditions in that area. Looking into the past infamous structures
failed due to this crucial step such as the Tacoma Narrows Bridge that failed
due to wind loading. Design standards in
different locations are imperative to the safety and wellness of the American
population and should be assessed before plans to develop a structure even
begin.
Source:http://www.metalconstructionnews.com/articles/magazine-features/constructing-metal-buildings-across-the-us.aspx
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