الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
With increasing use of concrete as a construction material, the risk of exposure to high temperatures has also increased. However concrete acts as nonflammable construction material; most of its mechanical properties are changeable due to chemical and physical changes that may occur due to high temperatures effect. To be able to assess the structural safety of such structures after exposure to high temperature, it is important that the effect on strength of concrete should be well understood. This work provides the findings of this study on the behavior of normal strength concrete (NSC) and self-compacting concrete (SCC) under extreme temperature exposure conditions. The main objective of this investigation was to study the effect of transient high temperature exposure on the residual compressive and splitting tensile strengths after cooling of normal strength concrete and compare the behavior with that of self-compacting concrete. Both of the two types of concretes were incorporating mineral additives (silica fume (S.F)& air cooled slag (A.C.S)) as a partial replacement of the cement content. Also air cooled slag was added to some of the concrete mixes as a partial replacement of the fine and coarse aggregates. The test specimens were subjected to temperatures ranging from 200 to 1000°C and their behavior after cooling was compared to that observed at room temperature (RT). The experimental results showed that the use of S.F in concrete mixes, which may be exposed to high temperature exposure levels, was not recommended. Utilization of A.C.S as aggregates for concrete improved its performance under such conditions. A.C.S in the form of coarse aggregate was more efficient to achieve this goal than being in the form of fine aggregate. Utilizing the local A.C.S aggregate can be considered as a resource conservation as it reduces the need for natural aggregate. It would provide a good solution for deducting the cost of concrete production, prolonging the service life of concrete structures, and finally reducing the harmful environmental impact of such by-product.