Page 146 - Handbook of Thermal Analysis of Construction Materials
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Section 9.0 - Durability Aspects                             129



















































                              Figure 40. DTA of air-entrained 0.5 W/C cement paste saturated with brine of various
                              concentrations.



                                     Beddoe and Setzer [82]  carried out extensive investigations on the
                              freezing phenomenon in cement pastes, applying the DSC technique.
                              Themograms were obtained in the temperature range of 20 to -175°C. The
                              pores in the paste were classified into three groups, viz., macro, meso, and
                              micro of radii > 50, 2–50, and < 2 nm, respectively. Figure 41 shows DSC
                              curves of a cement paste containing different amounts of NaCl. Three
                              endothermal effects occur in some samples. A general displacement of
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