TY  - CONF
AU  - Stanić, Filip
AU  - Delage, Pierre
AU  - Cui, Yu-Jun
AU  - De Laure, Emmanuel
AU  - Versini, Pierre-Antoine
AU  - Schertzer, Daniel
AU  - Tchiguirinskaia, Ioulia
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3364
AB  - Based on tests carried out on a specific device allowing to determine the water retention and transport properties of granular media at low suctions, an alternative approach to Kunze and Kirkham’s method of accounting for the impedance effects due to the high air entry value ceramic disk when using Gardner’s method is proposed. Impedance effects are accounted for by proposing analytical solutions to the equations governing water transfers occurring within the specimen and the ceramic disk. By using some experimental data obtained on a volcanic granular substrate used for urban green roofs, the method is successfully compared to Kunze and Kirkham’s graphical method. Its advantages are to be simpler of use and not operator dependent. A detailed examination of the performance of our method compared to those of Gardner and Kunze and Kirkham is carried out based on experimental data, that confirm its validity.
PB  - E3S Web of Conferences
C3  - 4th European Conference on Unsaturated Soils (E-UNSAT 2020)
T1  - A new approach of accounting for impedance effects in Gardner’s method of determining the hydraulic conductivity of unsaturated soils
VL  - 195
DO  - 10.1051/e3sconf/202019503012
ER  - 

@conference{
author = "Stanić, Filip and Delage, Pierre and Cui, Yu-Jun and De Laure, Emmanuel and Versini, Pierre-Antoine and Schertzer, Daniel and Tchiguirinskaia, Ioulia",
year = "2020",
abstract = "Based on tests carried out on a specific device allowing to determine the water retention and transport properties of granular media at low suctions, an alternative approach to Kunze and Kirkham’s method of accounting for the impedance effects due to the high air entry value ceramic disk when using Gardner’s method is proposed. Impedance effects are accounted for by proposing analytical solutions to the equations governing water transfers occurring within the specimen and the ceramic disk. By using some experimental data obtained on a volcanic granular substrate used for urban green roofs, the method is successfully compared to Kunze and Kirkham’s graphical method. Its advantages are to be simpler of use and not operator dependent. A detailed examination of the performance of our method compared to those of Gardner and Kunze and Kirkham is carried out based on experimental data, that confirm its validity.",
publisher = "E3S Web of Conferences",
journal = "4th European Conference on Unsaturated Soils (E-UNSAT 2020)",
title = "A new approach of accounting for impedance effects in Gardner’s method of determining the hydraulic conductivity of unsaturated soils",
volume = "195",
doi = "10.1051/e3sconf/202019503012"
}

Stanić, F., Delage, P., Cui, Y., De Laure, E., Versini, P., Schertzer, D.,& Tchiguirinskaia, I.. (2020). A new approach of accounting for impedance effects in Gardner’s method of determining the hydraulic conductivity of unsaturated soils. in 4th European Conference on Unsaturated Soils (E-UNSAT 2020)
E3S Web of Conferences., 195.
https://doi.org/10.1051/e3sconf/202019503012

Stanić F, Delage P, Cui Y, De Laure E, Versini P, Schertzer D, Tchiguirinskaia I. A new approach of accounting for impedance effects in Gardner’s method of determining the hydraulic conductivity of unsaturated soils. in 4th European Conference on Unsaturated Soils (E-UNSAT 2020). 2020;195.
doi:10.1051/e3sconf/202019503012 .

Stanić, Filip, Delage, Pierre, Cui, Yu-Jun, De Laure, Emmanuel, Versini, Pierre-Antoine, Schertzer, Daniel, Tchiguirinskaia, Ioulia, "A new approach of accounting for impedance effects in Gardner’s method of determining the hydraulic conductivity of unsaturated soils" in 4th European Conference on Unsaturated Soils (E-UNSAT 2020), 195 (2020),
https://doi.org/10.1051/e3sconf/202019503012 . .

TY  - CONF
AU  - Stanić, Filip
AU  - Delage, Pierre
AU  - Cui, Yu-Jun
AU  - De Laure, Emmanuel
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3363
AB  - The water retention curve and the hydraulic conductivity function of a volcanic coarse granular material used as a substrate in an urban green roof in the Paris area was carried out on a newly developed device, in which low suctions were controlled. In the same cell, a hanging column system was used for controlling smaller suctions (up to 32 kPa ) and the axis translation technique for larger suctions (up to 50 kPa ). Water exchanges were monitored in connected tubes by using a high accuracy differential pressure transducer. The step changes in suction were also used to determine the hydraulic conductivity function by means of Gardner’s method, accounting for the impedance effects due to the high air entry value ceramic porous disk with Kunze and Kirkham’s method. van Genuchten and Brooks and Corey models were used for the water retention curve, but the hydraulic conductivity functions derived from these expressions appeared to lead to a significant under-estimation, confirming the need of operational and simple device for the experimental determination of the hydraulic conductivity function.
PB  - E3S Web of Conferences
T1  - Water retention and transfer properties of a Green roof volcanic substrate
VL  - 195
DO  - 10.1051/e3sconf/202019503011
ER  - 

@conference{
author = "Stanić, Filip and Delage, Pierre and Cui, Yu-Jun and De Laure, Emmanuel",
year = "2020",
abstract = "The water retention curve and the hydraulic conductivity function of a volcanic coarse granular material used as a substrate in an urban green roof in the Paris area was carried out on a newly developed device, in which low suctions were controlled. In the same cell, a hanging column system was used for controlling smaller suctions (up to 32 kPa ) and the axis translation technique for larger suctions (up to 50 kPa ). Water exchanges were monitored in connected tubes by using a high accuracy differential pressure transducer. The step changes in suction were also used to determine the hydraulic conductivity function by means of Gardner’s method, accounting for the impedance effects due to the high air entry value ceramic porous disk with Kunze and Kirkham’s method. van Genuchten and Brooks and Corey models were used for the water retention curve, but the hydraulic conductivity functions derived from these expressions appeared to lead to a significant under-estimation, confirming the need of operational and simple device for the experimental determination of the hydraulic conductivity function.",
publisher = "E3S Web of Conferences",
title = "Water retention and transfer properties of a Green roof volcanic substrate",
volume = "195",
doi = "10.1051/e3sconf/202019503011"
}

Stanić, F., Delage, P., Cui, Y.,& De Laure, E.. (2020). Water retention and transfer properties of a Green roof volcanic substrate. 
E3S Web of Conferences., 195.
https://doi.org/10.1051/e3sconf/202019503011

Stanić F, Delage P, Cui Y, De Laure E. Water retention and transfer properties of a Green roof volcanic substrate. 2020;195.
doi:10.1051/e3sconf/202019503011 .

Stanić, Filip, Delage, Pierre, Cui, Yu-Jun, De Laure, Emmanuel, "Water retention and transfer properties of a Green roof volcanic substrate", 195 (2020),
https://doi.org/10.1051/e3sconf/202019503011 . .

TY  - JOUR
AU  - Stanić, Filip
AU  - Delage, Pierre
AU  - Cui, Yu-Jun
AU  - De Laure, Emmanuel
AU  - Versini, Pierre-Antoine
AU  - Schertzer, Daniel
AU  - Tchiguirinskaia, Ioulia
PY  - 2019
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3369
AB  - Gardner's (1956, https://doi.org/10.2136/sssaj1956.03615995002000030006x) transient method of measuring the hydraulic conductivity function of unsaturated media has been largely used, together with the improved graphical method proposed by Kunze and Kirkham (1962, https://doi.org/10.2136/sssaj1962.03615995002600050006x) to account for the impedance effect resulting from using a low hydraulic conductivity ceramic disk in porous plate testing. These methods are nowadays seldom used, since they have been replaced by numerical back analysis and methods for parameter optimization. Based on tests carried out on a specific device allowing to determine the water retention and transport properties of water in a coarse granular media at low suctions (up to 50 kPa), it was found necessary to account (i) for impedance effects and (ii) for the effects of nonconstant suction increments, as is often the case when using the hanging column technique. A new method is proposed to account for impedance effects, based on an analytical solution of the equations governing water transfer. The validity of this method is tested by considering experimental data from three distinct materials: a coarse green roof volcanic substrate, poorly graded sand, and undisturbed silty clay. Compared to the graphical method Kunze and Kirkham's method, it is less operator-dependent and hence more objective. It is also simpler than numerical back analysis methods, since it does not require any use of numerical code or parameter optimization algorithm, providing a more direct and reliable access to the hydraulic conductivity. An analytical solution is also proposed to solve the problem resulting from the application of a nonconstant suction increment.
PB  - Wiley Open Access
PB  - American Geophysical Union
T2  - Water Resources Research
T1  - Two Improvements to Gardner's Method of Measuring the Hydraulic Conductivity of Non‐saturated Media: Accounting for Impedance Effects and Non‐constant Imposed Suction Increment
IS  - 1
VL  - 56
DO  - 10.1029/2019WR026098
ER  - 

@article{
author = "Stanić, Filip and Delage, Pierre and Cui, Yu-Jun and De Laure, Emmanuel and Versini, Pierre-Antoine and Schertzer, Daniel and Tchiguirinskaia, Ioulia",
year = "2019",
abstract = "Gardner's (1956, https://doi.org/10.2136/sssaj1956.03615995002000030006x) transient method of measuring the hydraulic conductivity function of unsaturated media has been largely used, together with the improved graphical method proposed by Kunze and Kirkham (1962, https://doi.org/10.2136/sssaj1962.03615995002600050006x) to account for the impedance effect resulting from using a low hydraulic conductivity ceramic disk in porous plate testing. These methods are nowadays seldom used, since they have been replaced by numerical back analysis and methods for parameter optimization. Based on tests carried out on a specific device allowing to determine the water retention and transport properties of water in a coarse granular media at low suctions (up to 50 kPa), it was found necessary to account (i) for impedance effects and (ii) for the effects of nonconstant suction increments, as is often the case when using the hanging column technique. A new method is proposed to account for impedance effects, based on an analytical solution of the equations governing water transfer. The validity of this method is tested by considering experimental data from three distinct materials: a coarse green roof volcanic substrate, poorly graded sand, and undisturbed silty clay. Compared to the graphical method Kunze and Kirkham's method, it is less operator-dependent and hence more objective. It is also simpler than numerical back analysis methods, since it does not require any use of numerical code or parameter optimization algorithm, providing a more direct and reliable access to the hydraulic conductivity. An analytical solution is also proposed to solve the problem resulting from the application of a nonconstant suction increment.",
publisher = "Wiley Open Access, American Geophysical Union",
journal = "Water Resources Research",
title = "Two Improvements to Gardner's Method of Measuring the Hydraulic Conductivity of Non‐saturated Media: Accounting for Impedance Effects and Non‐constant Imposed Suction Increment",
number = "1",
volume = "56",
doi = "10.1029/2019WR026098"
}

Stanić, F., Delage, P., Cui, Y., De Laure, E., Versini, P., Schertzer, D.,& Tchiguirinskaia, I.. (2019). Two Improvements to Gardner's Method of Measuring the Hydraulic Conductivity of Non‐saturated Media: Accounting for Impedance Effects and Non‐constant Imposed Suction Increment. in Water Resources Research
Wiley Open Access., 56(1).
https://doi.org/10.1029/2019WR026098

Stanić F, Delage P, Cui Y, De Laure E, Versini P, Schertzer D, Tchiguirinskaia I. Two Improvements to Gardner's Method of Measuring the Hydraulic Conductivity of Non‐saturated Media: Accounting for Impedance Effects and Non‐constant Imposed Suction Increment. in Water Resources Research. 2019;56(1).
doi:10.1029/2019WR026098 .

Stanić, Filip, Delage, Pierre, Cui, Yu-Jun, De Laure, Emmanuel, Versini, Pierre-Antoine, Schertzer, Daniel, Tchiguirinskaia, Ioulia, "Two Improvements to Gardner's Method of Measuring the Hydraulic Conductivity of Non‐saturated Media: Accounting for Impedance Effects and Non‐constant Imposed Suction Increment" in Water Resources Research, 56, no. 1 (2019),
https://doi.org/10.1029/2019WR026098 . .

TY  - JOUR
AU  - Stanić, Filip
AU  - Cui, Yu-Jun
AU  - Delage, Pierre
AU  - De Laure, Emmanuel
AU  - Versini, Pierre-Antoine
AU  - Schertzer, Daniel
AU  - Tchiguirinskaia, Ioulia
PY  - 2019
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3368
AB  - The determination of the water retention curve (WRC) and hydraulic conductivity function (HCF) of a specific volcanic coarse granular material used as a substrate for urban green roofs in Europe was carried out on a newly developed specific device in which low suctions, typical of coarse granular materials, were controlled. Smaller suctions (up to 32 kPa) were imposed by using a hanging column system, and larger suctions (between 32 and 50 kPa) were imposed by using the axis translation technique in the same cell. The changes in suction during the tests were monitored by using a high accuracy differential pressure transducer. They were also used to determine the HCF by means of both Kunze and Kirkham’s and Gardner’s methods. The former technique was used at low suctions (<4 kPa) to account for the impedance effects due to the high air entry value ceramic porous disk and the latter was used between 4 and 50 kPa. Good comparability was observed in the data from both methods, demonstrating the good perfor- mance of the device. The mathematical expressions of the WRC of van Genuchten and Brooks and Corey were used, and a good fitting with our experimental data was obtained. Conversely, the HCFs derived from these expressions appeared to lead to a significant underestimation, con- firming the need of an operational and simple device for the experimental determination of the HCF. Also, this material proved to be an appropriate material for green urban infrastructures, because of its lightweight, satisfactory water retention capability and hydraulic conductivity.
PB  - ASTM Compass
PB  - ASTM International (American Society For Testing and Materials)
T2  - Geotechnical Testing Journal (GTJ)
T1  - A Device for the Simultaneous Determination of the Water Retention Properties and the Hydraulic Conductivity Function of an Unsaturated Coarse Material; Application to a Green-Roof Volcanic Substrate
IS  - 3
VL  - 43
DO  - 10.1520/GTJ20170443
ER  - 

@article{
author = "Stanić, Filip and Cui, Yu-Jun and Delage, Pierre and De Laure, Emmanuel and Versini, Pierre-Antoine and Schertzer, Daniel and Tchiguirinskaia, Ioulia",
year = "2019",
abstract = "The determination of the water retention curve (WRC) and hydraulic conductivity function (HCF) of a specific volcanic coarse granular material used as a substrate for urban green roofs in Europe was carried out on a newly developed specific device in which low suctions, typical of coarse granular materials, were controlled. Smaller suctions (up to 32 kPa) were imposed by using a hanging column system, and larger suctions (between 32 and 50 kPa) were imposed by using the axis translation technique in the same cell. The changes in suction during the tests were monitored by using a high accuracy differential pressure transducer. They were also used to determine the HCF by means of both Kunze and Kirkham’s and Gardner’s methods. The former technique was used at low suctions (<4 kPa) to account for the impedance effects due to the high air entry value ceramic porous disk and the latter was used between 4 and 50 kPa. Good comparability was observed in the data from both methods, demonstrating the good perfor- mance of the device. The mathematical expressions of the WRC of van Genuchten and Brooks and Corey were used, and a good fitting with our experimental data was obtained. Conversely, the HCFs derived from these expressions appeared to lead to a significant underestimation, con- firming the need of an operational and simple device for the experimental determination of the HCF. Also, this material proved to be an appropriate material for green urban infrastructures, because of its lightweight, satisfactory water retention capability and hydraulic conductivity.",
publisher = "ASTM Compass, ASTM International (American Society For Testing and Materials)",
journal = "Geotechnical Testing Journal (GTJ)",
title = "A Device for the Simultaneous Determination of the Water Retention Properties and the Hydraulic Conductivity Function of an Unsaturated Coarse Material; Application to a Green-Roof Volcanic Substrate",
number = "3",
volume = "43",
doi = "10.1520/GTJ20170443"
}

Stanić, F., Cui, Y., Delage, P., De Laure, E., Versini, P., Schertzer, D.,& Tchiguirinskaia, I.. (2019). A Device for the Simultaneous Determination of the Water Retention Properties and the Hydraulic Conductivity Function of an Unsaturated Coarse Material; Application to a Green-Roof Volcanic Substrate. in Geotechnical Testing Journal (GTJ)
ASTM Compass., 43(3).
https://doi.org/10.1520/GTJ20170443

Stanić F, Cui Y, Delage P, De Laure E, Versini P, Schertzer D, Tchiguirinskaia I. A Device for the Simultaneous Determination of the Water Retention Properties and the Hydraulic Conductivity Function of an Unsaturated Coarse Material; Application to a Green-Roof Volcanic Substrate. in Geotechnical Testing Journal (GTJ). 2019;43(3).
doi:10.1520/GTJ20170443 .

Stanić, Filip, Cui, Yu-Jun, Delage, Pierre, De Laure, Emmanuel, Versini, Pierre-Antoine, Schertzer, Daniel, Tchiguirinskaia, Ioulia, "A Device for the Simultaneous Determination of the Water Retention Properties and the Hydraulic Conductivity Function of an Unsaturated Coarse Material; Application to a Green-Roof Volcanic Substrate" in Geotechnical Testing Journal (GTJ), 43, no. 3 (2019),
https://doi.org/10.1520/GTJ20170443 . .