Use of hydrated cement pastes (HCP) as a CO2 sponge

. Seventy-eight graphs were plotted to describe and analyze the dependences of the height and roughness irregularities on the water-to-cement ratio and on the porosity of the cement hydrates. The results showed unambiguously that the water-to-cement ratio or equivalently the porosity of the specimens has a decisive influence on the irregularities of the fracture surfaces of this material. The experimental results indicated the possibility that the porosity or the value of the water-to-cement ratio might be inferred from the height irregularities of the fracture surfaces. It was hypothesized that there may be a similarly strong correlation between porosity and surface irregularity, on the one hand, and some other highly porous solids, on the other, and thus the same possibility to infer porosity from the surfaces of their fracture remnants.

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Effect of free water removal from early-age hydrated cement pastes on thermal analysis

Construction and Building Materials ◽

10.1016/j.conbuildmat.2009.06.004 ◽

2009 ◽

Vol 23 (11) ◽

pp. 3431-3438 ◽

Cited By ~ 49

Author(s):

Elke Knapen ◽

Ozlem Cizer ◽

Koenraad Van Balen ◽

Dionys Van Gemert

Keyword(s):

Thermal Analysis ◽

Free Water ◽

Early Age ◽

Water Removal ◽

Hydrated Cement ◽

Cement Pastes

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Microstructure and Porosity of Metakaolin Blended Cements

MRS Proceedings ◽

10.1557/proc-136-275 ◽

1988 ◽

Vol 136 ◽

Cited By ~ 4

Author(s):

P. Bredy ◽

M. Chabannet ◽

J. Pera

Keyword(s):

Compressive Strength ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Hydrated Cement ◽

Cement Pastes ◽

Blended Cements ◽

Mercury Intrusion ◽

Pozzolanic Cement

ABSTRACTFive compositions with 10% to 50% metakaolin for cement substitution were studied. The rate of hydration was studied from the compressive strength after up to 6 months of curing and from the hydrates formed (DTA-XRD). The metakaolin addition considerably reduced portlandite content in the hydrated cement and contributed to the formation of hydrated gehlenite which is not present in OPC paste. The microstructure study (SEM) shows that pozzolanic cement pastes were less crystallized than plain pastes. Mercury intrusion was used to measure porosity of hydrated cement pastes. The porosity with blended cements was higher than that with OPC, except for 10 and 20% metakaolin substitution. Evolution of the pore size distribution was studied: the pozzolanic pastes enhance small diameters.

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