PORE STRUCTURE CHARACTERISTIC OF ROLLER COMPACTED CONCRETE WITH SPECIAL MINERAL ADMIXTURE

摘要

There is more than 50% content of mineral admixture in roller compacted concrete(RCC), and it has serious influence on RCC's performance. The hydration and pore structureproperties of RCC with combined mineral admixtures of ground limestone powder and ground granulated blast-furnace slag (SL mineral admixture) were studied with the methodsof SEM and MIP. The experiment results of microstructure were compared with that of RCCincorporated with fly ash. The results show that the hydration products of SL mineraladmixture-cement paste are C-S-H gel, Ca(OH)2, and Aft and some cement grains remainsunhydrated. There are 35.06% of porosity and 0.095 μm of average pore size at 28 days thatof 23.29% and 0.025 μm at 120 days of SL mineral admixture-cement paste. After long-agecuring, pore structure of SL mineral admixture-cement paste is better than that of fly ash-cement paste. The application experience of SL RCC in a hydropower station of Chinarevealed that the performances of SL RCC can meet the design requirements and theconstruction of this hydropower station has good quality.