Disasters come in many shapes, sizes, and forms yet all are detrimental to people and structures of all types. The most terrifying of all disasters are natural disasters, the force of nature is rivaled by no man made disaster. One of the natural disasters that has terrorized as well as fascinated humans through out history is the earthquake. Most earthquakes are associated with areas such as Southern California or China, but the most detrimental aspect of disaster is the element of suprise. In this case areas such as Central North America and North Turkey have been visited by the violent shock of a mid-continent earthquake. These earthquakes are violent and cause mass amounts of structural damage and total destruction of many structures. Concrete being a very brittle material is affected greatly during an earthquake but through technology many advancements have been made to compensate for the damaging effects caused by an earthquake. This paper will discuss mid-continent earthquakes of the past, their effect on concrete structures, problems effecting concrete structures, and alternative materials and solutions to bypass those problems during future earthq

Earthquakes seldomly rear their ugly head, but when they do there is generally mass destruction involved. Studies of past earthquakes and future predictions can give the concrete industry an advantage in designing more earthquake damage resistant

Earthquakes with deformation, liquefaction of the soils, and ground shaking also have an impact on the regularity of concrete structures. Regularity deals with the distribution of load over the entire structure to maintain uniform soundness. Ground shaking and deformation can cause a sudden change in the stiffness, strength, or mass on either horizontal or vertical planes resulting in the redistribution of lateral loads. Irregularity results in setbacks of appendages, changes in story height or even the participation of nonstructural components. An example of this is the columns of tall building pounding on the roof of a shorter building. Strength and stiffness irregularities often result in torsional response. Torsion due to asymmetric failure of infill panels also contributes to building failures (Ghosh 1991).

was tremendous as a result of the 7.5 Richter scale rated earthquake where many buildings were flattened. "Deformation was evident in the Izmut Bay where the fault leaves the eastern side of the bay and slumps along the crack formed scarps (USGS 1999). Sag ponds were a result of the liquefaction that occurred along the strike slip fault. This earthquake was devastating to the residents of northern Turkey but a lot of valuable information was extracted in order to prevent that magnitude of disaster in the future.

Technology also governs the materials and design of the structures. "Battelle's Pacific Northwest Laboratories has found a connection between the use of steel fibers and the resistance the failure during earthquake like conditions ( Henager 1980). "Technology has also brought the concrete industry carbon fiber for reinforcing columns as well as using steel jackets or reinforced concrete to support existing columns (Roberts 1995)." These techniques strengthen the columns allowing for better continuity.

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Approximate Word count = 2148
Approximate Pages = 9 (250 words per page double spaced)