TITLE:
Surface Properties of Cement Paste Evaluated by Scanning Probe Microscopy
AUTHORS:
Yuya Sakai
KEYWORDS:
Cement Paste, Scanning Probe Microscopy, Surface Potential, Frictional Resistance, Viscoelasticity
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.6 No.4,
September
29,
2016
ABSTRACT: The microscopic physical properties of Hardened Cement Paste (HCP) surfaces were evaluated by using Scanning Probe Microscopy (SPM). The cement pastes were cured under a hydrostatic pressure of 400 MPa and the contacting surfaces with a slide glass during the curing were studied. Scanning Electron Microscope (SEM) observation at a magnification of 7000 revealed smooth surfaces with no holes. The surface roughness calculated from the SPM measurement was 4 nm. The surface potential and the frictional force measured by SPM were uniform throughout the measured area 24 h after the curing. However, spots of low surface potential and stains of low frictional force and low viscoelasticity were observed one month after curing. This change was attributed to the carbonation of hydrates.