نوع مقاله : یادداشت فنی
نویسندگان
1 بخش مهندسی عمران - دانشگاه باهنر کرمان .
2 بخش مهندسی عمران - دانشگاه شهید باهنر کرمان .
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Based on significant role of concrete in construction industry, this material is known as one of the most common used substance for researchers, this special consideration leads to invention of new generation concrete and various admixtures with different applications. Self compacting concrete (SCC) is one of these new combinations which was offered at 1986 due to nonqualified conventional concrete (vibrated concrete) in 1980 decade. Self compacting concrete has well application in construction procedure by passing freely around and through reinforcement and covers all the spaces inside the framework and can be compacted by its own weight without need of any vibration. Lower time and lower cost of construction, lower sound pollution and high homogeneous concrete are some advantages of SCC. In more recent years the tendency to use high strength self compacting concrete, HSSCC are increased rapidly and also the use of nano particles in developing materials has gained enormous attention due to their extreme fine size. Nono technology has made an outstanding progress in various fields and materials and its usage is going on to increase. Materials smaller than 100 nanometer are involved in this technology and their application in HSSCC needs to be investigated. Mechanical properties (compressive and tensile strength, modules of elasticity, shrinkage and creeping) and durability (durability against freezing and thawing cycles, sulfate attack and carbonation) of concrete are seems to be dependent on nano behavior rather tan the micro behavior, and improvement of nano may leads to progress in concrete quality much more than before. In this investigation, by trial and error procedure, different mix design of nano HSSCC were caste and tested to reach a so called standard nano HSSCC in fresh matrix phase (i.e., the rheology of fresh nano HSSCC such as; values of slump flow diameter, $T_{50}$, L-box, V-funnel, J-ring, and column segregation). Based on the results obtained, the two best so-called standard mix designs were selected for further investigations. The effect of two types of fillers, lime stone powder and ozzolan on parameters like uni axial compressive strength of concrete, ranged of absorbed water and concrete strength determination on confined situation which is performed by the triaxial test. Failure analysis of triaxial test stresses is performed and normal main stress and shear stress along with Mohrs circles are achieved. The results are indicated that, natural and artificial using of pozzolan materials in nano HSSCC causes increase in strength at older ages and concrete durability.
کلیدواژهها [English]
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