Effects of Concrete Mix Design on Earthquake Resistance

There are a variety of structures which utilize concrete in their construction. The concrete structure may be reinforced, unreinforced, precast, or poured on site. The structure may only use concrete in a few elements or be almost entirely constructed from the material. The wide spread and diverse uses for concrete make it a substance which should be paid great attention to when looking to optimize structures in seismic regions and when analyzing data from earthquake reconnaissance. Though there are significant differences between the uses of concrete in structures, it is certain that the properties of the concrete should match the task they are meant to perform. For instance, concrete which is intended to perform well in seismic regions should ideally be designed differently from typical concrete. This is a practice which is already in place in newer structures in seismic zones. During earthquake reconnaissance, I feel it would be especially beneficial to note the differences between concrete mixed with seismic codes considered and those which do not consider seismic activity. To discuss the properties for which concrete is designed, it is necessary to stress that the materials used to make a concrete mix can vary distinctly from region to region, and the methods by which concrete is poured may be significantly different than the typical codes seen in the United States. These variances lead to differences in the quality of mix which can be produced. To analyze the impact of concrete mix design during earthquake reconnaissance, it would be beneficial to become familiar with the typical ingredients of concrete structures in the area in order to assess the general quality of concrete. The type of aggregate used affects bond strength and therefore affects the overall strength and quality of the concrete. One should also note the general practices used for pouring concrete such as the use of vibrators, knowledge of ideal pouring time and conditions, and