Most of the buildings we live, work, and spend time in, are designed
in conjunction with civil engineers. More generally, the infrastructure of the
world is designed primarily by civil engineers. We all spend large amounts of
our time on these roads, in these buildings, and whether we realize it or not,
our lives are heavily influenced by the work of civil engineers. The water we
drink is cleaned and transported in facilities designed by civil engineers, and
the waste we create is disposed of in landfills and other processing plants that
civil engineers helped create. Because of the sheer numbers of people that
civil engineers work impacts, safety is a key consideration.
Innovation is key in the continual push to make our civil
structures safer. One example of this is in areas where earthquakes are an ever-present
risk. As the West Coast of the United States was settled in mass, building
practices remained traditional and very similar to building practices in other
parts of the US. But, because of the San Andreas Fault, California is always at
risk for large earthquakes. For many decades, an earthquake along the San
Andreas meant serious damage to cities as well as large death rates. But, with superior
construction techniques, and better understanding of how the soils would
behave, the risk of death has dropped significantly. This same trend can be
seen in many other areas as well.
Aftermath of 1906 earthquake in San Francisco |
Even with this current trend to safer infrastructure and
buildings, corners sometimes get cut and mistakes are made. Frequently,
projects are a careful balance of factors including cost and safety. Often times,
customers are trying to minimize the costs associated with projects, and this
can, in rare cases, lead to project that are less safe than they should be.
During the design process, it is very important to determine to what level
something should be designed for.
An example of this is
the levees in New Orleans that catastrophically failed, and caused the city too
be flooded several years ago. The levees were designed to withstand a storm surge
up to a certain level, but when hurricane Katrina came, the surge was greater
than it was designed for and the structure failed. Now, if they had designed
the levee to withstand a greater surge, the project would have gone up in cost.
This illustrates some of the trade-offs that must be made when designing
projects. Design work is seldom ever black and white. Rather, it is more of a
gradient were trade-offs must be made. In the case of the levees in New
Orleans, they obviously leaned too far on the side of saving money.
There are many takeaways from these themes. Most
importantly, it is important for engineers not to trade safety and security for
cost savings. After the research and studies are done it is important that engineers
follow the guidelines and lean towards over-designing for all contingencies
rather than trying to save too much money. If engineers follow this rule of
thumb, we can continue to improve the safety of our buildings and infrastructure.