Capillary rise kinetics of some building materials
M Karoglou1, A Moropoulou, A Giakoumaki
1School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece. margo@central.ntua.gr
Journal of Colloid and Interface Science
|March 9, 2005
Summary
Water penetration in masonry, primarily via capillary rise, causes deterioration. This study models capillary rise kinetics, finding material properties like pore radius significantly impact moisture height and can predict water uptake.
Area of Science:
- Building materials science
- Civil engineering
- Material physics
Background:
- Water presence in masonry is a key factor in material deterioration.
- Capillary rise is the primary mechanism for water penetration into building materials.
- Understanding water transport is crucial for building durability.
Purpose of the Study:
- To investigate the kinetics of capillary rise in various building materials.
- To propose a kinetic model for predicting moisture height.
- To identify factors influencing the rate of capillary rise.
Main Methods:
- Studied capillary rise in four stones, two bricks, and six plasters.
- Developed a first-order kinetic model based on Darcy's law.
- Analyzed the relationship between material characteristics and capillary rise.
Main Results:
- A first-order kinetic model accurately described the capillary rise phenomenon.
- The equilibrium moisture height was found to be dependent on material properties.
- The capillary height time constant was strongly influenced by material characteristics, particularly average pore radius.
Conclusions:
- Material characteristics significantly affect the kinetics of capillary rise in building materials.
- The average pore radius is a key predictor of the capillary height time constant.
- The proposed model provides a method for predicting water penetration in masonry.
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01:20Porosity and Absorption of Aggregate
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01:23Pore Size Distribution
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01:24Carbonation Shrinkage
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01:19Capillarity in Fluid
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