Model for the formation of microstructure in cement paste during hydration

Title: Model for the formation of microstructure in cement paste during hydration
Author(s): R. Nothnagel, H. Budelmann
Paper category : conference
Book title: International RILEM Symposium on Concrete Modelling - ConMod '08
Editor(s): E. Schlangen and G. De Schutter
Print-ISBN: 978-2-35158-060-8
e-ISBN: 978-2-35158-076-9
Publisher: RILEM Publications SARL
Publication year: 2008
Pages: 361 - 368
Total Pages: 8
Nb references: 14
Language: English

Abstract: The porous space of cement paste is formed during hydration. Processes of transport and chemical reactions are proceeding in the capillaries influenced by the environmental conditions. Therefore the hydration process mainly determinates the state, the later behaviour and the durability of the material.
The model introduced here is delivering a description of the capillary pore space during hydration and of its state at the beginning of the period of use. The three-dimensional characterization of the porous structure of Portland cement paste and its development is based upon the constitutive volumetric approach of Powers & Brownyard. The process is described by means of finite elements. It contains the dissolution of non-hydrated cement and the formation of hydration products within the porous space. In opposite to existing models the model being developed is giving more detailed information on the local porosity distribution and the capillary microstructure.
Taking results of mercury intrusion into account the local porosity distribution can be transformed into a pore size distribution. By help of this procedure the detection of pores over a wide range of the capillary pore space can be put into practice.

Online publication: 2009-06-15
Publication type : full_text
Public price (Euros): 0.00