Seite - 1506 - in Book of Full Papers - Symposium Hydro Engineering

figure 1 show QC tests for aggregate in RCC dams and aggregate production in stone crusher. Table 1 QC tests for aggregate in RCC dams In RCC dam, the physical properties of the source area were measured in the design phase. Tests were carried out to determine rock types, strengths, grading, particle shapes, freeze-thaw resistance, abrasion resistance, specific gravity, water absorption, moisture content and the content of impurities. The chemical soundness of the rock was also investigated and includes tests for alkali-silica reaction (ASR), sulphate resistance and others. Some of these tests are carried out during construction to ensure that the source material and the aggregate produced conform to the design assumptions as embodied in the specifications. Test frequencies will depend on the consistency of the source. Table 3 shows QC chart of aggregate production. Fig. 1 Aggregate production in stone crusher (Uma Oya project-Sri Lanka) 2.2. CEMENTITIOUS MATERIALS In RCC dams the cement used in concrete determined according to ASTM C150. This determination is based on environmental, materials and structures conditions. For mass concrete, as in the case of RCC Dams, cements with low heat generation -Type 2 or pozzolanic should be used. For cementitious materials, most important is the control of uniformity, which can vary considerably due to heterogeneous sources or caused by the grinding process. The rate of cement consumption can be very high for RCC dams and the turnover of on-site storage can be rapid. Considerable reliance has to be placed 1506