Journal of Materials Science

, Volume 20, Issue 1, pp 303–315 | Cite as

A study of ultrafine porosity in hydrated cements using small angle neutron scattering

  • D. Pearson
  • A. J. Allen
Papers

Abstract

Small angle neutron scattering makes use of the neutron contrast due to differences in the scattering power between small, particulate regions and the general background medium, and has only very recently been applied to study the porosity in hydrated cement systems. The technique is applied to pore sizes below approximately 30 nm and produces data on pore size distribution, pore volume and pore shape without recourse to drying techniques and the potential structural degradation which may occur. Results indicate a bi-modal pore size distribution at approximately 5 and 10 nm diameter, with a total volume accounting for some several percent of the total cement block. The best estimate of the 5 nm pore shape is considered to be curved-faced tetrahedra. The pores appear to be relatively unaffected by changes in the water-to-cement ratio or accelerating admixture investigated, but macro defect free cement does show significant pore structure alteration.

Keywords

Porosity Pore Volume Pore Size Distribution Hydrated Cement General Background 

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Copyright information

© Chapman and Hall Ltd. 1985

Authors and Affiliations

  • D. Pearson
    • 1
  • A. J. Allen
    • 2
  1. 1.Materials Development DivisionAERE HarwellDidcotUK
  2. 2.Materials Physics DivisionAERE HarwellDidcotUK

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