Properties and CO2-curing enhancement of cement-based materials containing various sources of waste hardened cement paste powder

Cement-based materials have been traditionally formed by casting. The amount of water used in the casting process determines the porosity of the hardened material. The water requirements, and the tendency for cement grains to agglomerate, result in hardened cement paste having high porosity and a wide range of pore sizes. Consequently, such materials are not very strong and contain critical flaws whose dimensions are of the order of 0.1 mm. Although improvements in particle packing and particle dispersion to reduce porosity have resulted in significant increases in strength, such materials are still very brittle and have relatively low tensile and flexural strengths.

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The Thermal Deformation of Cement-Based Material at Low Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1081.279 ◽

2014 ◽

Vol 1081 ◽

pp. 279-283 ◽

Cited By ~ 1

Author(s):

Nan Zhang ◽

Juan Liao ◽

Tao Zhang ◽

Wen Zhan Ji

Keyword(s):

Low Temperature ◽

Cement Paste ◽

Low Temperatures ◽

Thermal Deformation ◽

Pore Solution ◽

Freezing Point ◽

Bulk Solution ◽

Hardened Cement ◽

Hardened Cement Paste ◽

Cement Based Materials

Thermal deformation of concrete at low temperature expands from-20°C to-50°C and contracts from-30°C to-10°C. Based on previous studies, the paper tries to explain the deformaion trend by analyzing freezing point of bulk solution and pore solution in saturated hardened cement paste. The result shows that it is critical to thermal deformation of cement-based materials at low temperature that pore solution in the pores smaller than 8 nm freezes.

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Electrical Resistivity and Dielectric Properties of Hardened Cement Paste and Mortar

MRS Proceedings ◽

10.1557/proc-411-407 ◽

1995 ◽

Vol 411 ◽

Cited By ~ 11

Author(s):

D. Buerchler ◽

B. Elsener ◽

H. Boehni

Keyword(s):

Electrical Resistivity ◽

Dielectric Properties ◽

Water Content ◽

Cement Paste ◽

Pore Solution ◽

Hardened Cement ◽

Hardened Cement Paste ◽

Solution Composition ◽

Cement Based Materials

ABSTRACTWater content, porosity, pore solution composition, resistivity and dielectric properties of hardened cement paste and mortar samples have been studied as a function of time and relative humidities. A model for the resistivity of cement based materials is presented and an interpretation of the dielectric properties is proposed.

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Influence of an Anti-Chloride Corrosion Admixture on Density of Cement-Based Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.1315 ◽

2012 ◽

Vol 430-432 ◽

pp. 1315-1319

Author(s):

Wei Zhang ◽

Xiao Yao ◽

Ru Mu

Keyword(s):

Pore Structure ◽

Cement Paste ◽

Sem Analysis ◽

Chloride Ions ◽

Mineral Admixture ◽

Hardened Cement ◽

Hardened Cement Paste ◽

Chloride Corrosion ◽

Steel Bar ◽

Cement Based Materials

A new admixture increasing the density of cement-base composites and hence preventing the penetration of chloride ions is developed and investigated. The new admixture is the combination of traditional mineral admixture and steel bar inhibitor. The composition of the admixture is optimized using water absorption tests. Then the effect of the new admixture on the workability of freshly mixed cement paste as well as the pore structure and SEM analysis of hardened cement paste is experimentally investigated. The results show that the new admixture is effective to increase the density of cement-based materials.

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