Study on the Influence of Minor Constituents in Blast Furnace Slag Rich Cement on the Thermal and Mechanical Properties of Concrete

Until now, the influence on the thermal and mechanical properties of concrete of SO 3 and calcium carbonate as minor constituents contained in binder used for concrete made with blast furnace slag rich cement was not clearly known, and neither was the optimum mixing ratio most effective for control of thermal cracking. To evaluate the influence of these minor constituents on the temperature and crack resistance properties of concrete, a simple adiabatic temperature rise test and examination by thermal stress testing machine (TSTM) were carried out in this study. The simple adiabatic temperature rise test evaluated mainly the thermal characteristics of the minor constituents under investigation, while the test using a TSTM, which is a test device that can simulate the behavior inside the member of a real structure, investigated mechanical properties such as creep characteristics, and crack resistance. Further, using the results of the simple adiabatic temperature rise test and the test using a TSTM, thermal stress analysis using a wall structure was carried out to determine the influence of minor constituents on crack resistance. As a result, as determined within the scope of this study, we found that the formation of ettringite and monosulfate accompanying the addition of SO 3 has an influence on the adiabatic temperature rise characteristic and the apparent mechanical properties, and that the addition of calcium carbonate has only a small influence on thermal properties.