200MPa급 초고강도 콘크리트의 자기수축 특성에 관한 실험적 연구

Low W/B ultra-high strength concrete has low porosity and discontinuous capillary tube in the cement milk. Within a few days after placement, autogenous shrinkage occur because of the quick drying from the self-desiccation. So, the possibility of cracking is higher than the normal strength concrete. In this study, the autogenous shrinkage deformation characteristics of ultra-high strength concrete that are different from the normal strength concrete were examined. A new shrinkage formula is suggested form the experiment data. The conclusion is as follows. 1) The 91days strength of the concrete combination that are W/B 12.5%, normal portland cement 55%, china silica fume 20%, GGBFS-2 20%, anhydrite 5% was the best result, 193.7MPa. So, it is the appropriate combination for the 200MPa grade ultra-high strength concrete. 2) The autogenous shrinkage deformation of W/B 20% ultra-high strength concrete can be predicted using the suggested shrinkage formula.