Considerations about statistical nanoindentation on hardened cement pastes

Title: Considerations about statistical nanoindentation on hardened cement pastes
Author(s): Pietro Lura, Pavel Trtik and Beat Münch
Paper category : conference
Book title: International RILEM Conference on Advances in Construction Materials Through Science and Engineering
Editor(s): Christopher Leung and K.T. WAN
ISBN: 978-2-35158-116-2
e-ISBN: 978-2-35158-117-9
Publisher: RILEM Publications SARL
Publication year: 2011
Pages: 56 - 62
Total Pages: 7
Nb references: 19
Language: English

Abstract: Nanoindentation is an experimental technique that allows in situ measurements of the elastic properties of materials. A development of the technique is statistical nanoindentation, where hundreds of single indentation tests are carried out in a grid on a multiphase material and the indentation elastic modulus and hardness of the single phases are then extracted with statistical methods from the frequency plots. This technique has been employed by several research groups to assess the mechanical properties of different calcium-silicate hydrate (C-SH) phases in hardened cement paste (HCP).
However, Focussed Ion Beam nanotomography on HCP shows that the homogenous C-S-H regions present in HCP are too small to cause independent and separate peaks in the elastic modulus plots. Moreover, the presence of phases other than C-S-H, namely unhydrated cement, calcium hydroxide, ettringite and capillary porosity may also produce spurious peaks. Another questionable aspect is the methodology used to extract the elastic modulus of the single phases from the frequency plots by fitting with Gaussian distributions.

Online publication: 2011-10-31
Publication type : full_text
Public price (Euros): 0.00