The thermogravimetric instrument (STA449F3, Selbu, Bavaria, Germany) was employed to measure the composition and relative content of hydration products of different binders. The hydrated sample powder weighed about 20 mg and was placed in a corundum crucible. The sample together with the Al2O3 crucible was elevated from room temperature of 25 °C to 800 °C at N2 with a controlled heating rate of 10 °C/min. The content of chemically bound water (BW) and portlandite (CH) was calculated according to Equation (4) and Equation (5) [56 (link)], respectively.
WBW=W50W550W550×100
WCH=(W400W500)W550×7418×100 
where the W50, W400, W500, and W550 was the weight of specimens at 50 °C, 400 °C, 500 °C, and 550 °C.
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