Latest Earthquake Preparation Techniques

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Latest Earthquake Preparation Techniques

Seismic activity is the most challenging, and most heavily invested in, civil engineering disciplines. Today, engineers use materials and building methods especially geared towards dealing with this menace. However, these modern techniques can cause more harm than good when not properly used with older structures. Historical buildings come with their own challenges, and seismic retrofitting does not come with a single solution for all structural integrity issues; however, as time passes, engineers and the government are making progress in the fight against Mother Nature.

A Big Challenge for Civil Engineers

Earthquakes pose an enhanced threat to structures compared to other natural disasters, because this particular disaster type offers no time to prepare. This leaves engineers with an enormous task; since it is impossible to determine where seismic activity will occur well in advance, engineers can only forecast potential high-risk areas. Armed with this information, the engineers then ensure that all structures in a large geographic region can stand up to the next earthquake that may occur. This process is costly and time-consuming. Historical structures, however, come with added complications.

Modern Seismic Retrofitting

Contemporary engineering designs call for more resilient materials and framing techniques than older methods. Born from experience, engineers have discovered they must employ better building tactics to ensure public safety. These techniques involve using hardened materials such as steel and reinforced concrete. They offer excellent protection for today’s modern structures; however, a problem arises when modern earthquake preparation techniques meet historical structures. When builders use reinforced concrete, a modern building staple, disastrous consequences can accompany seismic activity when the new concrete is not integrated correctly with a historic structure.

Historical Building Techniques and Seismic Activity

There are several factors that make protecting historical structures from seismic activity more challenging than protecting modern constructs. Older structure owners often do not diligently maintain the building’s structural integrity over time. Even if an owner maintains a historic building’s aesthetic appearance, the owner may not realize that combining modern construction techniques with old ones, without a full engineering survey, can serve to weaken a structure during seismic activity. Additionally, a property owner may have used different building techniques. Each structure requires a thorough inspection to uncover its structural intricacies. These historical building techniques – which involve using materials such as stone, clay or horizontal timbers – often do not fare well when improperly combined with their modern peers.

Utah Averts Disaster

In Utah, the State Capitol Building benefitted from diligent city civil engineers’ watchful eyes. The engineers inspected the Utah Capitol building around 2003, and made an alarming discovery. As the State Building’s structure rose, the concrete quality degraded drastically. Apparently, as the project neared completion, the builders began to run out of cement mix. As was often done in that time, when big builds overran budget constraints, the builders did whatever it took to complete the project. To build out the structure, workers mixed more and more water into the concrete mixture to stretch the material. Additionally, time degraded much of the structure’s foundation. Engineers fixed these errors and turned to the base isolation technique to make the structure and its foundation safe again.

The Utah State Building is Reborn

When engineers surveyed the Utah State building around 2003, they determined that even a minor earthquake could destabilize the structure. This resulted in the city shutting down the building for a seismic retrofit. Engineers not only wanted to make the structure safe, they also wanted to maintain the building’s structural heritage. The engineers used base isolation, a technique that involves replacing the building foundation with a bridge-like support, reducing seismic vibration impact. Engineers anticipate that the building is now protected from large earthquakes that trouble the area almost every 350 years. Some property owners are resigned to use much less expensive measures to shore up their structures. This is the case for many in California, where the state has instituted a financing program to help protect homeowners from seismic activity damage.

California’s Battle with Nature

California is synonymous with earthquake activity. In 1971, Southern California suffered from a large-scale, 6.6 magnitude earthquake that killed 65 residents and injured 2,500 others. The seismic activity ruined transportation routes, ruptured sewage and gas lines and sent emergency services into turmoil. Later, in 1987, another major earthquake hit California. This one was not as severe; however, it caused almost $360 million in damages. After repeated incidents like these, in 2011, California instituted the California Residential Mitigation Program.

Relief for California Residents

California has established a program that helps homeowners protect their residences from earthquake damage. The program offers a grant that homeowners can use to have their building structures seismically retrofitted. By offering these funds, the state hopes to reduce the damage caused when a seismic event occurs. The California Residential Mitigation Program, also named the “Earthquake Brace and Bolt Program,” is intended to bring all structures up to a new seismic code, reducing personal and property damage. Homeowners can use the grant funds for retrofitting that prevents their homes from coming off of the foundation during earthquakes. The program requires special engineering planning and work for foundations over four feet tall.

Earthquake activity presents many engineering challenges. Contemporary engineering practices are more effective at dealing with these challenges. Seismic engineers work to devise building methods that incorporate advanced materials and building techniques, but these techniques often clash with older building methods and materials. The effect time has on a structure is in itself damaging, and seismic engineers continually work to make sure that people remain safe in any structure during earthquake activity.

Learn More

Civil engineers play a crucial role in engineering the structural solutions of tomorrow and plan, design, construct, and operate the infrastructure essential to our modern lives. As a student in the online Master of Science in Civil Engineering program, you can enhance your quantitative decision-making skills and learn how to justify managerial decisions with data. You will also explore the capabilities of modern management technologies and discover how to successfully leverage these tools to maximize efficiencies in your projects and on your teams.

Sources

http://www.pasadenastarnews.com/general-news/20160213/remembering-the-lessons-of-southern-californias-history-of-earthquakes
http://www.getty.edu/conservation/publications_resources/newsletters/30_1/between_two.html

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https://www.earthquakebracebolt.com/HomeownerRegistration