Evolution of crack patterns on shcc as function of imposed strain
Title: Evolution of crack patterns on shcc as function of imposed strain
Author(s): P. Wang, F.H. Wittmann, T.J. Zhao and W.L. Huang
Paper category : conference
Book title: 2nd International RILEM Conference on Strain Hardening Cementitious Composites (SHCC2-Rio)
Editor(s): R.D. Toledo Filho, F.A. Silva, E.A.B. Koenders and E.M.R. Fairbairn
Publisher: RILEM Publications SARL
Publication year: 2011
Pages: 217 - 224
Total Pages: 8
Nb references: 5
Abstract: The enormous ductility of SHCC as compared to conventional cement-based materials is due to multi crack formation in the cementitious matrix. The crack width is controlled by PVA fibres. If SHCC is exposed to aggressive environment liquids and gases may penetrate through the micro-cracks. Durability will then depend on the crack width distribution. In this contribution experiments on dumbbell specimens are described. The crack width distribution has been determined as function of the imposed strain under tension. It could be shown that the distribution of crack width can be described reasonably well by a lognormal distribution.
It was found that the mean or expectation value of the crack width distribution measured on a formed surface is higher than the corresponding value on a finished surface. The expectation value hardly depends on the imposed strain, but the probability to find wider cracks increases.
It is concluded that the permeability of SHCC can be predicted by means of a weighted lognormal distribution. The weight function, however, is yet to be determined. It is suggested that SHCC should be optimized with respect to the crack width distribution.
Online publication: 2012-01-25
Publication type : full_text
Public price (Euros): 0.00