The Experts below are selected from a list of 20013 Experts worldwide ranked by ideXlab platform
B B Sabir - One of the best experts on this subject based on the ideXlab platform.
-
Sorptivity and strength of air cured and water cured pc pfa mk concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
-
Sorptivity and strength of air-cured and water-cured PC–PFA–MK concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
-
Sorptivity AND WATER ABSORPTION OF MORTARS INCORPORATING WASTE CLAY BRICK
2001Co-Authors: M. O'farrell, S Wild, B B SabirAbstract:This paper reports the results of an investigation of the Sorptivity of mortar that contains varying amounts of ground brick from different European bricks. Waste clay brick deriving from four European countries was ground to roughly cement fineness and used to partially replace cement in quantities of 0, 10, 20 and 30% in mortars. The Sorptivity and water absorption of these mortars were tested for curing periods of up to one year. The presence of ground brick does not have a significant effect on the water absorption of mortar. Sorptivity however, is affected considerably by not only the presence of ground brick but also by brick composition. Initially, the presence of ground brick in mortar increases its Sorptivity. As curing periods increase, the Sorptivity values for ground brick mortars decrease at a rate that is greater than that seen in mortars whose binder is 100% portland cement. This indicates that the ground brick decreases the capillarity of the mortar and this is attributed to the production of additional C-S-H gel. The additional C-S-H gel, in effect, refines the pore structure of the mortar and this is reflected in the increase in the compressive strength obtained for these mixes.
-
A water Sorptivity test for martar and concrete
Materials and Structures, 1998Co-Authors: B B Sabir, S Wild, M. O'farrellAbstract:Cet article décrit un appareil d'essai pour mesurer l'absorption unidirectionnelle de l'eau par le mortier et le béton. Les données résultant des essais sont contrôlées au moyen d'un logiciel spécialement conçu installé sur PC, et ces résultats sont directement utilisés pour obtenir la sorptivité mesurée en g/mm^2/min^1/2. A titre d'exemple, on a utilisé l'appareil pour déterminer la sorptivité d'un mortier dans lequel le ciment Portland ordinaire avait été partialement remplacé par les briques de récupération partialement concassées. Les résultats présentés ici démontrent la validité de l'essai, et le fait que l'appareil et la méthodologie ont une sensibilité suffisante pour détecter les différences entre les sorptivités des différents mortiers étudiés. Les variations de la sorptivité en fonction du temps de cure et de la composition du mélange ont été déterminées. L'article présente également les résultats d'essais d'absorption totale de l'eau menés sur les éprouvettes utilisées pour les essais de sorptivité, après leur reconditionnement, ainsi que les résultats d'essais de résistance à la compression pour tous les mortiers étudiés. This paper describes a test rig to measure the uni-directional water absorption of mortar and concrete. The test data acquisition is controlled by purpose written software installed on a PC and the results are utilised directly to obtain the Sorptivity measured in g/mm^2/min^1/2. As an example the apparatus was used to obtain the Sorptivity of mortar in which the ordinary Portland cement was partially replaced by ground waste brick obtained from different sources. The results presented demonstrate the validity of the test, and the apparatus and the methodology are shown to be of sufficient sensitivity in detecting the differences between the sorptivities of the various mortars tested. The variation in the Sorptivity with curing time and mixture composition was determined. The paper also gives the results of total water absorption test conducted on the Sorptivity test specimens, after being reconditioned, and the results of compressive strength tests for all the mortars investigated.
-
A water Sorptivity test for martar and concrete
Materials and Structures, 1998Co-Authors: B B Sabir, S Wild, M. O'farrellAbstract:This paper describes a test rig to measure the uni-directional water absorption of mortar and concrete. The test data acquisition is controlled by purpose written software installed on a PC and the results are utilised directly to obtain the Sorptivity measured in g/mm2/min1/2. As an example the apparatus was used to obtain the Sorptivity of mortar in which the ordinary Portland cement was partially replaced by ground waste brick obtained from different sources. The results presented demonstrate the validity of the test, and the apparatus and the methodology are shown to be of sufficient sensitivity in detecting the differences between the sorptivities of the various mortars tested. The variation in the Sorptivity with curing time and mixture composition was determined. The paper also gives the results of total water absorption test conducted on the Sorptivity test specimens, after being reconditioned, and the results of compressive strength tests for all the mortars investigated.
J Albergel - One of the best experts on this subject based on the ideXlab platform.
-
determining soil saturated hydraulic conductivity and Sorptivity from single ring infiltration tests
European Journal of Soil Science, 2007Co-Authors: J Touma, Marc Voltz, J AlbergelAbstract:Summary The difference between the cumulative infiltration occurring during three-dimensional axisymmetric and one-dimensional vertical flow is a linear function of time. The slope of this line is a function of the source radius, initial and final volumetric soil water contents and the soil Sorptivity. This allows the determination of the Sorptivity and saturated conductivity of the soil from data of axisymmetric flow in a single ring of small diameter under negligible head of water. The method is based on the optimization of the Sorptivity and saturated conductivity on the one-dimensional vertical cumulative infiltration inferred from axisymmetric flow data. To examine the reliability of the method to determine these parameters, numerical three- and one-dimensional data are generated on soils with known hydrologic properties from the literature. The linearity versus time of the difference of the two types of flow is verified. Several physically based expressions for the vertical cumulative infiltration as a function of time are considered. The optimized values of the Sorptivity and saturated conductivity are compared to the their real known values. Despite the large errors on the optimized parameters, namely the saturated conductivity, the error on the vertical predicted cumulative infiltration is limited to 10%. This makes possible the application of this method on a large scale for hydrological modelling purposes.
-
Determining soil conductivity and Sorptivity from single ring infiltration tests
European Journal of Soil Science, 2007Co-Authors: J Touma, Marc Voltz, J AlbergelAbstract:The difference between the cumulative infiltration occurring during three-dimensional axisymmetric and one-dimensional vertical flow is a linear function of time. The slope of this line is a function of the source radius, initial and final volumetric soil water contents and the soil Sorptivity. This allows the determination of the Sorptivity and saturated conductivity of the soil from data of axisymmetric flow in a single ring of small diameter under negligible head of water. The method is based on the optimization of the Sorptivity and saturated conductivity on the one-dimensional vertical cumulative infiltration inferred from axisymmetric flow data. To examine the reliability of the method to determine these parameters, numerical three- and one-dimensional data are generated on soils with known hydrologic properties from the literature. The linearity versus time of the difference of the two types of flow is verified. Several physically based expressions for the vertical cumulative infiltration as a function of time are considered. The optimized values of the Sorptivity and saturated conductivity are compared to the their real known values. Despite the large errors on the optimized parameters, namely the saturated conductivity, the error on the vertical predicted cumulative infiltration is limited to 10%. This makes possible the application of this method on a large scale for hydrological modelling purposes.
S Wild - One of the best experts on this subject based on the ideXlab platform.
-
Sorptivity and strength of air cured and water cured pc pfa mk concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
-
Sorptivity and strength of air-cured and water-cured PC–PFA–MK concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
-
Sorptivity AND WATER ABSORPTION OF MORTARS INCORPORATING WASTE CLAY BRICK
2001Co-Authors: M. O'farrell, S Wild, B B SabirAbstract:This paper reports the results of an investigation of the Sorptivity of mortar that contains varying amounts of ground brick from different European bricks. Waste clay brick deriving from four European countries was ground to roughly cement fineness and used to partially replace cement in quantities of 0, 10, 20 and 30% in mortars. The Sorptivity and water absorption of these mortars were tested for curing periods of up to one year. The presence of ground brick does not have a significant effect on the water absorption of mortar. Sorptivity however, is affected considerably by not only the presence of ground brick but also by brick composition. Initially, the presence of ground brick in mortar increases its Sorptivity. As curing periods increase, the Sorptivity values for ground brick mortars decrease at a rate that is greater than that seen in mortars whose binder is 100% portland cement. This indicates that the ground brick decreases the capillarity of the mortar and this is attributed to the production of additional C-S-H gel. The additional C-S-H gel, in effect, refines the pore structure of the mortar and this is reflected in the increase in the compressive strength obtained for these mixes.
-
A water Sorptivity test for martar and concrete
Materials and Structures, 1998Co-Authors: B B Sabir, S Wild, M. O'farrellAbstract:Cet article décrit un appareil d'essai pour mesurer l'absorption unidirectionnelle de l'eau par le mortier et le béton. Les données résultant des essais sont contrôlées au moyen d'un logiciel spécialement conçu installé sur PC, et ces résultats sont directement utilisés pour obtenir la sorptivité mesurée en g/mm^2/min^1/2. A titre d'exemple, on a utilisé l'appareil pour déterminer la sorptivité d'un mortier dans lequel le ciment Portland ordinaire avait été partialement remplacé par les briques de récupération partialement concassées. Les résultats présentés ici démontrent la validité de l'essai, et le fait que l'appareil et la méthodologie ont une sensibilité suffisante pour détecter les différences entre les sorptivités des différents mortiers étudiés. Les variations de la sorptivité en fonction du temps de cure et de la composition du mélange ont été déterminées. L'article présente également les résultats d'essais d'absorption totale de l'eau menés sur les éprouvettes utilisées pour les essais de sorptivité, après leur reconditionnement, ainsi que les résultats d'essais de résistance à la compression pour tous les mortiers étudiés. This paper describes a test rig to measure the uni-directional water absorption of mortar and concrete. The test data acquisition is controlled by purpose written software installed on a PC and the results are utilised directly to obtain the Sorptivity measured in g/mm^2/min^1/2. As an example the apparatus was used to obtain the Sorptivity of mortar in which the ordinary Portland cement was partially replaced by ground waste brick obtained from different sources. The results presented demonstrate the validity of the test, and the apparatus and the methodology are shown to be of sufficient sensitivity in detecting the differences between the sorptivities of the various mortars tested. The variation in the Sorptivity with curing time and mixture composition was determined. The paper also gives the results of total water absorption test conducted on the Sorptivity test specimens, after being reconditioned, and the results of compressive strength tests for all the mortars investigated.
-
A water Sorptivity test for martar and concrete
Materials and Structures, 1998Co-Authors: B B Sabir, S Wild, M. O'farrellAbstract:This paper describes a test rig to measure the uni-directional water absorption of mortar and concrete. The test data acquisition is controlled by purpose written software installed on a PC and the results are utilised directly to obtain the Sorptivity measured in g/mm2/min1/2. As an example the apparatus was used to obtain the Sorptivity of mortar in which the ordinary Portland cement was partially replaced by ground waste brick obtained from different sources. The results presented demonstrate the validity of the test, and the apparatus and the methodology are shown to be of sufficient sensitivity in detecting the differences between the sorptivities of the various mortars tested. The variation in the Sorptivity with curing time and mixture composition was determined. The paper also gives the results of total water absorption test conducted on the Sorptivity test specimens, after being reconditioned, and the results of compressive strength tests for all the mortars investigated.
J Bai - One of the best experts on this subject based on the ideXlab platform.
-
Sorptivity and strength of air cured and water cured pc pfa mk concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
-
Sorptivity and strength of air-cured and water-cured PC–PFA–MK concrete and the influence of binder composition on carbonation depth
Cement and Concrete Research, 2002Co-Authors: J Bai, S Wild, B B SabirAbstract:Abstract The paper reports the influence of the composition of Portland cement–pulverised fuel ash–metakaolin (PC–PFA–MK) binders on Sorptivity and strength development of PC–PFA–MK concrete cured both in air and in water and on carbonation depth, and relates this to measured changes in Sorptivity of the concrete. Concrete mixtures covering four different total cement replacement levels (10%, 20%, 30% and 40%) for PC–PFA–MK concrete with various MK/PFA proportions, water and air cured for up to 18 months, were investigated. The change in compressive strength and Sorptivity with age at all cement replacement levels under both water and air curing are compared with those of the control PC concrete. The results presented in this paper form part of an investigation into the optimisation of a ternary blended cementitious system based on ordinary PC, PFA and MK for the development of high-performance concrete.
Christopher Hall - One of the best experts on this subject based on the ideXlab platform.
-
Beyond the Sorptivity: definition, measurement and properties of the secondary Sorptivity
Journal of Materials in Civil Engineering, 2018Co-Authors: Andrea Hamilton, Christopher HallAbstract:AbstractCapillary imbibition in brick, stone, and concrete occurs in two stages. The primary process, which occurs in the standard test to measure Sorptivity, is a spontaneous imbibition in which a...
-
The temperature variation of the water Sorptivity of construction materials
Materials and Structures, 2017Co-Authors: Ioannis Ioannou, Cleopatra Charalambous, Christopher HallAbstract:The Sorptivity is used widely to characterise water dynamics in construction materials. Yet its variation with temperature has been little investigated. We report the results of a collaborative study between two laboratories in which the temperature dependence of the Sorptivity of ten materials has been measured in part or all of the range 5–45 °C. The materials cover a wide range of compositions and of numerical Sorptivity values. We find that the Sorptivity is about 50% greater at 45 °C than at 5 °C, and that, with one exception, the temperature coefficient is similar in all the materials studied. This shows that for practical purposes the value of the Sorptivity of an individual material at any temperature in this range may be estimated from a single measured value. The observed variation with temperature is attributed to the changes in the viscosity and surface tension of water, and is as predicted by a simple classical scaling of capillary dynamics, assuming that neither the wetting index nor the capillary moisture content vary with temperature. One of the materials studied, Lympia chalk, shows a somewhat smaller temperature variation than predicted by this scaling. We comment that commonly-used standards do not recognise adequately that the Sorptivity varies with temperature.
-
On the role of organic adlayers in the anomalous water Sorptivity of Lépine limestone
Journal of colloid and interface science, 2004Co-Authors: Ioannis Ioannou, William D. Hoff, Christopher HallAbstract:Sorptivity data are reported for the capillary absorption of water, ethanol, propan-2-ol, and n-heptane by the calcitic limestone Lepine (Lavoux a grain). The data confirm that the water Sorptivity is anomalously low, an indication of partial wetting by water. Results are expressed in terms of a wetting index. The water Sorptivity increases after heat treatment and chemical oxidation by hydrogen peroxide bleaching, while the Sorptivity with organic liquids is unchanged. These treatments, therefore, increase the water wetting index. The results provide strong evidence that the presence of a natural organic adlayer is responsible for the anomalously low water Sorptivity of this particular limestone. This natural water repellency effect may be exploited in developing chemical treatments to modify the water transport properties of stone.
-
Effect of non-sorptive inclusions on capillary absorption by a porous material
Journal of Physics D, 1993Co-Authors: Christopher Hall, William D. Hoff, Moira WilsonAbstract:The absorption of water into a porous material containing non-sorptive inclusions is analysed in terms of unsaturated flow theory. Expressions are obtained for the effect of inclusions on the permeability, the hydraulic conductivity, the hydraulic diffusivity and the Sorptivity. New data on the water Sorptivity S of gypsum plaster containing additions of sand ranging from 0 to 0.49 volume fraction alpha support the theoretical relation S'/S=1-1.25 alpha +0.26 alpha 2 approximately for the Sorptivity. This result provides indirect confirmation of the expressions for the other quantities on which the Sorptivity relation depends.
