| 요약2 |
Recently ultra high strength concrete is actively being developed and studied, and this trend is explained with the following effects. Technological effects expected from the application of ultra high strength concrete include the reduction of section, the decrease of structure mass and the improvement of workability. As for the reduction of section, the use of ultra high strength concrete is effective for plane and height, and the effect is even higher when it is applied to high?rise buildings. The decrease of concrete mass resulting from high strength is advantageous for earthquake resistance, reduces the use of earthquake?resistant members, and brings resource substitution effects. In addition, forms can be removed early thanks to self?fillability and early expression of strength resulting from the high fluidity, and this increases construction efficiency and shortens construction period. Recently there is increasing interest and investment in high?rise buildings throughout the world, and countries are competing for higher buildings in order to display national status and technological power through high?rise buildings. In addition, the use of concrete materials in steel?frame building is increasing as residential buildings are growing higher. Currently the application of ultra high strength concrete is limited to high?rise buildings and protective buildings for special purposes. However, its application is expected to expand to attain the effects of ultra high strength concrete. The present study carried out an experiment to derive the mixture ratio of ultra high strength concrete, the design standard strength of which was using ordinary Portland cement. The basic experiment was performed with changing water binder ratio, unit quantity, and additive substitution rate. In order to examine the applicability of members, we made reduced simulated members and measured hydration heat and core strength. The objective of this study is to examine the suitability of mixture ratio through experiment of basic physical properties and provide materials for the field application of ultra high strength concrete. |