PREDICTION OF PERMEABILITY FROM WATER VAPOR SORPTION ISOTHERM OF CEMENT-BASED MATERIALS

Author(s): Dongdong Zhang, Kefei Li
Paper category: Proceedings
Book title: Proceedings of the International RILEM Conference
Materials, Systems and Structures in Civil Engineering 2016
Segment on
Moisture in Materials and Structures
Editor(s): Kurt Kielsgaard Hansen, Carsten Rode and Lars-Olof Nilsson
Print-ISBN: 978-2-35158-230-5
ISBN: 978-2-35158-178-0
e-ISBN : 978-2-35158-179-7
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 34-43
Total Pages: 10
Language : English

Abstract: This paper presents the mechanisms involved in the water transport in porous cement-based
materials. Then two models, complete multi-phase model and its simplified model, are
established for moisture transport in porous cement-based materials. The water vapor sorption
isotherms (WVSI) were measured for cement pastes and mortars. Then these WVSI curves
are converted to water characteristic curves and the intrinsic permeability of cement-based
materials is regressed from the desorption process in WVSI measurement. The results show:
(1) the simplified model and complete model obtain similar values of permeability for
desorption at RH=60% while the regression of simplified model has notable error for
desorption in RH=18%; (2) the simplified model is valid for water transport under moderate
humidity (~60%) and above; (3) the method of determining intrinsic permeability from WVSI
and moisture transport model is feasible for indirect measurement in laboratory.

Online publication : 2016
Publication type : full_text
Public price (Euros) : 0.00