Summary: | 博士 === 國立臺灣科技大學 === 營建工程系 === 93 === This study tries to analyze the microstructure of HPC containing slag and fly ash, and the following methods are employed: SRA, NMR, MIP, SEM, LOI, Electrical Resistivity and Permeability. The test results show that, at the early age inside the cement paste with fly ash, [SiO2(OH)]-2 ionic bond forms C2SH2(B), and [SiO3(OH)]-3 forms C2SH2(A). Afwillite (one kind of C-S-H). Since the Ca2+ ion sticks on the surface of fly ash particle, causing the spoiling effect, the Ca2+ content is reduced and then the forming of nuclide is delayed. On the other side, fly ash and C3A can produce a hexagonal-layered protection which helps put off the hydration of C3A, and therefore there is no hydration product for C2S, C3A and C4AF. By the test of SRA and those of NMR, MIP, SEM, Electrical Resistivity and Permeability, the outcomes from macroview and microview both illustrate that the pozzalanic reaction of fly ash and slag can reduce the content of calcium hydroxide to fill the capillary porosity. Thus the microstructure order of the complex material is rearranged, and then the compression strength and resistivity are enhanced. At the same time, the permeability is reduced and more durability is gained.
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