Sunday, April 26, 2015

Ethical Dilemmas

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.

Wednesday, April 8, 2015

California's Water Crisis

Water is one of the most important resources in the world, and its availability is vital for humans. Having an abundance of fresh, clean water is very important for our society to function and thrive. As human populations have continued to increase and we have started to use industrial applications, our need for water has also continued to grow at a rapid rate. Now, in certain parts of the world, our need for fresh water is beginning to eclipse the earth’s ability to regenerate it. The management, collection and treatment of fresh water has always been at the forefront of civil engineers responsibilities.

A picture from the annual snow measuring. Typical snow levels are between 6 to 7 feet
Recently in California, the governor, Jerry Brown, used an executive order to impose a 25 percent reduction in water usage throughout the state. This move puts the United States’ most populous state in uncharted territory as California has never imposed mandatory water restrictions before. The announcement from the governor came directly following California’s annual snow pack measuring in the Sierra Nevada Mountains, where they have had a record drought year.

Some of the features of the new plan being put into place in California include, increasing the cost for high volume users, reducing excess water usage in urban areas, and increasing waste-water reuse. The state will have to continue to deplete their reserves which includes heavy pumping from aquifers and reservoirs. Although the state is not running out of water, the rate at which they are depleting their reserves is unsustainable.

This new aggressive policy may just be the beginning of major change throughout the country as many of the aquifers and reservoirs in the southwest have continuously been depleted in recent years due both to drought, and over consumption. Because of this water shortage, many are calling for the construction of seawater desalination plants along the coast. These plants could supplement the water supplies of the regions in which they are built, but present many design challenges. In addition to the call for desalination plants, the Southwest’s freshwater infrastructure is under the microscope as people look to make the system more efficient, as well as reduce consumption.

As stated earlier, there are many challenges associated with desalination plants. One of the major hurdles to be overcome are the massive amount of energy needed to run the plant. Because of this large energy consumption, the water made from the plant is much more costly to produce then natural water. This means that for the most part, the plant is only used in times of intense drought. Another obstacle is what to do with the salt the plant removes from the water. Many of the current plants around the world simply put the salt back into the ocean. Recently however, it has been shown that this high salt concentration close to the plant has a negative impact on the local ecosystem. Because of these drawbacks, many in California are hesitant to go ahead with the costly construction of a plant.

Over the next several years we will probably see a lot of change in how water is used in California as well as to the infrastructure. It will be interesting to see how they handle the challenges they are presented. As populations continue to increase and water becomes scarcer, many areas around the world will have to wrestle with the same problems that California is facing.


Tuesday, March 24, 2015

ETFE: A Material of the Future

Engineers are always on the lookout for new technologies and materials that decrease the price of projects and allow greater freedom in the design of projects. Before the advent of mass-produced iron and steel, buildings were limited to the constraints of stone and lumber. Very tall buildings were not feasible. The taller a stone building was built, the thicker the bottom levels of the building would have to be to bear the weight of the structure. An example of this is the Philadelphia City Hall, which when built in 1901, was designed to be the tallest structure in the world. As the structure of the building was built of brick and stone, the first floor walls were up to 22 feet thick at parts. Before Philadelphia’s City Hall was completed however, the Eiffel Tower surpassed it as the tallest structure at almost twice the height. This illustrates how new materials and techniques can affect the buildings we build.
Over 40 years ago, a material called ETFE was developed by DuPont. Although this material has been around for a while, it is just starting to see prominent use in architectural applications. Some notable buildings that make use of this polymer are The Water Cube used in the 2008 Beijing Olympics, the Allianz Arena football stadium in Germany, and the Minnesota Vikings Stadium in Minneapolis which is currently under construction.


The material is a polymer that is extruded into thin, transparent sheets that are used as cladding, roofing and façade systems. The material is very unique in that it is strong, very light, and highly resistant to corrosive forces. The material does not degrade under UV light or other radioactive forces, and does not corrode or react with pollution or air. Additionally, ETFE has many of the same properties as PTFE or Teflon that you may have seen on non-stick pots and pans. Just like Teflon, ETFE has a very low coefficient of friction and water and snow slide off of it very easily. There is little need to clean the material as the dust, dirt, and other contaminants simply get carried off with rain water.  Because of these properties, ETFE is highly resistant to discoloration or deterioration. As mentioned earlier, ETFE is often used in roofing and cladding applications. In the Minnesota Vikings stadium for example, just over half the roof will be made of the material, giving it a unique, clear ceiling.
Another benefit of the material is its light weight. ETFE can weigh 1-3 percent of traditional cladding systems. This combined with its strength allows dramatic cost savings as the surrounding structure does not have to support as great of a load. There are also many applications for which traditional systems would not work. ETFE has the additional benefit of being able to stretch to three times its length before failing. The material is also highly recyclable, and following its useful life, can be completely recycled for re-use. This means the environmental impact of the material is much lower than comparable claddings.

In conclusion, ETFE will continue to see new use and more widespread application as new uses and implementations are found for it. There are many exciting new possibilities for the widespread use of ETFE and it will continue to be adopted. As the material is still relatively new the limitations and full possibilities are not even close to being fully explored.

Wednesday, March 4, 2015

Introduction To Civil Engineering

Civil Engineering
Civil engineering is one of the oldest professions in the world and can trace its origins to the beginning of civilization. Ever since humans began moving from a hunter gatherer life style towards permanent settlements, civil structures have had to be built and designed to meet the needs of the people living in them. As people started to gather in permanent settlements, many new problems were created. How do you build structures that last longer? How do you deal with unpredictable flooding that happens in the spring? How do you keep the settlement free of human and animal waste to prevent disease? Although the clear distinction as a civil engineer has not always been there, people have been working to solve these problems.

The field of civil engineering deals with the design, construction, and maintenance of civil structures. This might include roads, buildings, bridges, dams, sewage systems, and often involves working with municipalities. Often times, civil engineering is broken up in to subcategories such as structural, water-resources, environmental, transportation, geotechnical and construction engineering.


Qualities of an Engineer
There are certain qualities that good engineers usually possess. Generally, good engineers in all disciplines poses strong problem solving and analytic skills. These skills are particularly vital because engineers often work with lots of data and complicated requirements, and must dissect and identify the data and requirements to come up with a solution. Engineers want to create and innovate and work with the newest technology and techniques to come up with unique solutions. Communication skills and the ability to work on teams are also vitally important skills. One might consider the design of a new skyscraper for example. Think of how many different departments and engineers must work together to come up with a design. There is no room for miscommunication on such a project as even a small misunderstanding in the design could compromise the project. No matter how brilliant the work, if someone cannot communicate it effectively, it is worthless.

On a day to day basis, the daily work of a civil engineer may vary greatly. A structural engineer might spend the majority of his time working from his office, preforming calculations and working on designs. A construction engineer might split his time between job sites where he is overseeing and ensuring the quality of the work, and the office where he is in meetings and files paperwork.

Integrity
Commitment to ethical integrity is very important in all engineering fields. Things that are designed by engineers can be very widely implemented and have a huge effect on people who are using them. A faulty bridge or building design where corners were cut can result in the death the occupants or drivers. Such mistakes can kill or injure hundreds of people. A faulty part in an automobile that did not go through rigorous testing could catastrophically fail in thousands of cars resulting in countless accidents. Because of this responsibility, the role of ethics is extremely important in all engineering disciplines. Many companies and professional engineering associations have codes of ethics that members must abide by.