Experimental determination on the capillary water absorption coefficient of porous building materials: A comparison between the intermittent and continuous absorption tests

2020 ◽  
Vol 28 ◽  
pp. 101091 ◽  
Author(s):  
Jiang Lu ◽  
Ke Wang ◽  
Ming-Liang Qu
Keyword(s):  
Absorption Coefficient ◽  
Water Absorption ◽  
Experimental Determination ◽  
Building Materials ◽  
Capillary Water ◽  
Water Absorption Coefficient ◽  
Capillary Water Absorption ◽  
Porous Building Materials ◽  
Continuous Absorption

scholarly journals Influence of Crystalline Admixtures on the Short-Term Behaviour of Mortars Exposed to Sulphuric Acid

Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 82 ◽  
Author(s):  
Victoria García-Vera ◽  
Antonio Tenza-Abril ◽  
José Saval ◽  
Marcos Lanzón
Keyword(s):  
Compressive Strength ◽  
Absorption Coefficient ◽  
Water Absorption ◽  
Sulphuric Acid ◽  
Cementitious Materials ◽  
Pulse Velocity ◽  
Capillary Water ◽  
Short Term ◽  
Water Absorption Coefficient ◽  
Capillary Water Absorption

Using durable materials is a sustainable solution for extending the lifetime of constructions. The use of crystalline admixtures makes cementitious materials more durable. They plug pores, capillary tracts and microcracks, blocking the entrance of water due to the formation of crystals that prevent the penetration of liquids. The literature has covered the performance of these admixtures on concrete, but studies on mortars are still scarce. The aim of this study is to investigate the effect of an aggressive environment (sulphuric acid solution—3 wt%) on mortars produced with different percentages of a crystalline admixture (1%, 1.5% and 2% by weight of cement content). Physical and mechanical properties were studied after immersing the mortars in a H2SO4 solution for 90 days. It was found that, after a 90-day sulphuric acid exposure, mortars with the crystalline admixture showed greater compressive strength than the control mortar, besides exhibiting lower mass loss. However, the crystalline admixture did not produce any significant effect on the capillary water absorption coefficient. In a nonaggressive environment, and in the short term, the crystalline admixture did not have a significant effect on the compressive strength, the capillary water absorption coefficient or the ultrasonic pulse velocity.

Simulieren der kapillaren Wasseraufnahme von porösen Werkstoffen des Bauwesens / Modelling of the Capillary Water Absorption of Porous Building Materials

2000 ◽  
Vol 6 (3) ◽  
pp. 293-306
Author(s):  
J. Elsen ◽  
F. de Barquin
Keyword(s):  
Water Absorption ◽  
Pore Size ◽  
Building Materials ◽  
Automated Image Analysis ◽  
Invasion Percolation ◽  
Capillary Water ◽  
Capillary Suction ◽  
Capillary Water Absorption ◽  
Porous Building Materials ◽  
3D Network

Abstract Profound knowledge of the moisture transport in porous building materials is essential to understand and to improve their durability. Water flow in these materials is mainly driven by capillary forces and the capillary suction of a porous building material depends on its pore structure. We have designed a statistical model to simulate the capillary water absorption of porous building materials based on invasion percolation rules. A 3D-network with 30x30x100 sites was used and the trapping effect is included. The input for the simulated invasion percolation is a pore size distribution obtained by a stereological analysis of the results of automated image analysis measurements on SEM-BSE-images of polished sections. Pore size distributions of nine different materials have been determined experimentally by SEM and by MIP. The simulated absorption curves agree reasonably well with the experimental absorption curves.

Water-Resistance of Mortars with Lightweight Aggregates

2014 ◽  
Vol 634 ◽  
pp. 46-53 ◽  
Author(s):  
António Soares ◽  
Maria Júlio ◽  
Inês Flores-Colen ◽  
Laura Ilharco ◽  
Jorge de Brito ◽  
...  
Keyword(s):  
Absorption Coefficient ◽  
Water Absorption ◽  
Bulk Density ◽  
Silica Aerogel ◽  
Water Resistance ◽  
Lightweight Aggregates ◽  
Capillary Water ◽  
Water Absorption Coefficient ◽  
Vapour Permeability ◽  
Capillary Water Absorption

The incorporation of lightweight aggregates in cement-based coating mortars contributes to a better performance of some of their physical properties, influencing their hygrothermal behaviour. This paper analyses the effect of some lightweight aggregates (expanded clay, granulated cork and silica aerogel) on the following mortars’ characteristics: porosity, bulk density, capillary water absorption coefficient, drying index and water vapour permeability. The experimental results showed that low percentages of incorporation of lightweight aggregates led to more porous mortars with lower bulk density, higher capillary water absorption coefficient and greater drying facility, relative to the reference cement-based mortar. The incorporation of silica aerogel in cement-based mortars resulted in major differences in terms of water resistance, with significant benefits in terms of the drying process due to their porous structure.

scholarly journals Effects of Imposed Damage on the Capillary Water Absorption of Recycled Aggregate Concrete

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Qi Gao ◽  
Zhiming Ma ◽  
Jianzhuang Xiao ◽  
Fuan Li
Keyword(s):  
Absorption Coefficient ◽  
Water Absorption ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Capillary Absorption ◽  
Capillary Water ◽  
Aggregate Concrete ◽  
Capillary Water Absorption ◽  
Freeze Thaw ◽  
Loading Level

Capillary water absorption of concrete is closely related to its pore structure, permeability, and durability. This paper intensively investigates the effects of imposed damage, including freeze-thaw damage and loading damage, on the capillary water absorption of recycled aggregate concrete (RAC). Freeze-thaw cycle test, loading test, and the experiment of capillary water absorption were carried out, respectively. The results demonstrate that the addition of recycled coarse aggregate (RCA) results in the increase in the capillary absorption behavior of RAC without imposed damage, and there exists a linear correlation between the behaviors of capillary water absorption and chloride penetration of RAC. The imposed freeze-thaw damage or load damage of RAC boosts with the increase of RCA replacement percentages after suffering the same freeze-thaw cycles or loading level. The imposed freeze-thaw damage and load damage further lead to the increase in the capillary water absorption of RAC, and the capillary absorption coefficient of RAC increases linearly with the increased RCA replacement percentages, after suffering the same freeze-thaw cycles or loading level. Furthermore, capillary absorption coefficient increases linearly with the growth of imposed freeze-thaw damage or load damage degree, which can be used to estimate the capillary absorption behavior of RAC exposed to the extreme environment.

Ermittlung der Kapillartransportkoeffizienten mineralischer Baustoffe aus dem w-Wert / Estimating the capillary transport coefficients of mineral building materials from the water absorption coefficient

1997 ◽  
Vol 3 (3) ◽  
pp. 219-234
Author(s):  
M. Krus ◽  
A. Holm ◽  
Th. Schmidt
Keyword(s):  
Absorption Coefficient ◽  
Water Absorption ◽  
Building Materials ◽  
Transport Coefficients ◽  
Capillary Transport ◽  
Water Absorption Coefficient ◽  
Standard Material ◽  
Moisture Balance ◽  
Computer Calculations ◽  
Building Components

Abstract Computer calculations are of increasing importance for the assessment of moisture balance in building components, since modern calculation methods achieve good agreement with measurements. A broader application of these methods is hampered, however, by the laborious measurements needed to determine the capillary transport coefficients essential for the calculations. A new method is therefore presented which allows to estimate the coefficients from wellknown standard material properties (free capillary saturation, practical moisture content and water absorption coefficient). These coefficients are sufficient for estimative assessment of the moisture balance of many materials, as is demonstrated by comparison of suction profiles calculated in this way and measured profiles.

scholarly journals Built Heritage Evaluation: Manual Using Simple Test Methods

2021 ◽  
Author(s):  
A. Elena Charola ◽  
Jorge Otero ◽  
Paula T. DePriest ◽  
Robert J. Koestler
Keyword(s):  
Water Absorption ◽  
Building Materials ◽  
Test Methods ◽  
Capillary Water ◽  
Laboratory Methods ◽  
Water Absorption Coefficient ◽  
Built Heritage ◽  
Widespread Availability ◽  
Cultural Monuments

<p>This manual describes simple tests for evaluating the condition of built heritage and cultural monuments. The tests were selected for their simplicity and widespread availability, especially in countries where few institutions deal with the conservation of <a>important buildings or monuments</a> and where laboratories capable of the necessary analyses are scarce.</p> <p>Most tests can be carried out without the resources of a complete conservation laboratory. Methods include microscopy, ion test strips, the Scotch Tape test, RILEM tube water absorption, water vapor transmission, and three tests that can be run sequentially: capillary water absorption coefficient, total immersion, and evaporation curves.</p> <p>Some of these tests aid in the examination of building materials and the characterization of salts and other condition problems, which will help to determine the appropriate methods and materials for conservation and restoration.</p>

Sign in / Sign up

Export Citation Format

Share Document