FR2576414A1 - Apparatus for measuring the permeability of ground and more particularly formations with very low permeability, of the double ring type - Google Patents
Apparatus for measuring the permeability of ground and more particularly formations with very low permeability, of the double ring type Download PDFInfo
- Publication number
- FR2576414A1 FR2576414A1 FR8500696A FR8500696A FR2576414A1 FR 2576414 A1 FR2576414 A1 FR 2576414A1 FR 8500696 A FR8500696 A FR 8500696A FR 8500696 A FR8500696 A FR 8500696A FR 2576414 A1 FR2576414 A1 FR 2576414A1
- Authority
- FR
- France
- Prior art keywords
- permeability
- proximity sensor
- ground
- rings
- oscillating circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000035699 permeability Effects 0.000 title claims abstract description 21
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 5
- 238000005755 formation reaction Methods 0.000 title claims abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000005259 measurement Methods 0.000 claims abstract description 9
- 239000002689 soil Substances 0.000 claims description 6
- 239000000523 sample Substances 0.000 claims description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 239000002440 industrial waste Substances 0.000 description 2
- 230000008595 infiltration Effects 0.000 description 2
- 238000001764 infiltration Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D1/00—Investigation of foundation soil in situ
- E02D1/02—Investigation of foundation soil in situ before construction work
- E02D1/027—Investigation of foundation soil in situ before construction work by investigating properties relating to fluids in the soil, e.g. pore-water pressure, permeability
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/24—Earth materials
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- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- Hydrology & Water Resources (AREA)
- Structural Engineering (AREA)
- Dispersion Chemistry (AREA)
- Soil Sciences (AREA)
- Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
Description
La présente invention concerne un appareil de mesure de la perméabilité de terrains et plus particulièrement de formations très faibtement perméables, du type a double anneau. The present invention relates to an apparatus for measuring the permeability of terrains and more particularly of very weakly permeable formations, of the double ring type.
Dans certains cas ,il est nécassaire de pouvoir déterminer avec une très grande précision la perméabilité d'un sol, par exemple pour la mise en décharge de déchets industriels. La mesure du coefficient de perméabilité du soZ permet de ctasser tes sites pouvant être éventuellement retenus à cet effet en plusieurs classes. Ainsi pour les sites de première cZasse, dits "imperméables", pouvant recevoir des déchets industriels spéciaux, le coefficient de perméabilité doit être ésal ou inférieur à 1 .10-9 m/s sur une épaisseur au moins équivalente à 5 m. In some cases, it is necessary to be able to determine with very great precision the permeability of a soil, for example for the landfill of industrial waste. Measuring the permeability coefficient of soZ allows you to break down your sites, which can possibly be selected for this purpose in several classes. Thus for the first class, so-called "waterproof" sites that can receive special industrial waste, the permeability coefficient must be equal to or less than 1.10-9 m / s over a thickness at least equivalent to 5 m.
On connatt actuellement divers appareils pour la mesure de ta perméabilité d'un sol, ces appareils étant encore appelés "infiltromètres". L'un de ces appareils connus, dit à "double anneau",se compose de deux anneaux cylindriques coaxiaux en tôle d'acier, le diamètre intérieur de l'anneau extérieur étant en général doubte de celui de l'anneau intérieur. Ces deux anneaux sont munis chacun, à leur base, d'un couteau permettant de les enfoncer dans le sol sur une profondeur d'une dizaine de centimètres envi- ron. Deux réservoirs permettent d'alimenter l'appareil en eau en maintenant constamment une lame d'eau de S cm d'épaisseur environ à la surface du sol.L'un des réservoirs alimente l'anneau intérieur tandis que l'autre réservoir alimente l'espace annulaire compris entre l'anneau intérieur et l'anneau extérieur, au moyen d'une tuyauterie immergée dans la lame d'eau. On relève périodiquement le niveau de l'eau dans le premier réservoir alimentant l'anneau intérieur et cette mesure permet d'obtenir la courbe de la variation du volume infiltré cumulé, par unité de surface, en fonction du temps, en considérant une infiltration verticale sur l'aire de l'anneau intérieur.Par contre l'infiltration sur l'aire annulaire extérieure à l'anneau : ntérieur n'est pas contrôlée: elle a essentiellement pour but de compenser tes pertes d'eau par écoulement latéral et elle assure ainsi un écoulement pratiquement vertical dans la zone centrale. Various devices are currently known for measuring the permeability of a soil, these devices also being called "infiltrometers". One of these known devices, known as a "double ring", consists of two coaxial cylindrical rings of sheet steel, the inside diameter of the outside ring being generally less than that of the inside ring. These two rings are each provided, at their base, with a knife allowing them to be driven into the ground to a depth of about ten centimeters. Two tanks allow the device to be supplied with water while constantly maintaining a sheet of water about 5 cm thick on the ground surface. One of the tanks supplies the inner ring while the other tank supplies the annular space between the inner ring and the outer ring, by means of piping immersed in the water layer. The water level in the first reservoir supplying the inner ring is periodically noted and this measurement makes it possible to obtain the curve of the variation of the cumulative infiltrated volume, per unit area, as a function of time, considering a vertical infiltration. on the area of the inner ring.But against infiltration on the annular area outside the ring: ntérieur is not controlled: its main purpose is to compensate for your water losses by lateral flow and it thus ensures a practically vertical flow in the central zone.
Si un tel infiltromètre du type à doubtes anneaux permet d'effectuer des mesures satisfaisantes dans un grana nombre de cas, iZ s'est révélé toutefois nettement irsuffi- sant pour fournir des mesures de très grande précision. If such an infiltrometer of the double-ring type makes it possible to carry out satisfactory measurements in a large number of cases, iZ has however proved clearly insufficient to provide measurements of very high accuracy.
La présente invention vise à remédier à cet inconvérient en procurant un appareil de conception particutièrement simple, facite a mettre en oeuvre et donnant une très grande précision de ta mesure de l'ordre de 1.10-9m/s. The present invention aims to remedy this inconvenience by providing a device of particularly simple design, easy to implement and giving very high accuracy of your measurement of the order of 1.10-9m / s.
A cet effet cet appareil de mesure de la perméabiti- té de terrains et plus particulièrement de formations très faiblement perméables, du type à double anneau, comprenant deux anneaux cylindriques coaxiaux enfoncés dans le sol et contenant respectivement une lame d'eau centrale contenue dans l'anneau intérieur et une Zame d'eau annulaire contenue dans l'espace compris entre tes deux anneaux, est caractérisé en ce qu'il comprend, a ta partie supérieure de Z'an- eau interne un capteur de proximité faisant partie d'un circuit oscillant,associé à un flotteur flottant sur la surface de la lame d'eau centraZe et portant un élément modifiant la fréquence de résonance du circuit oscillant en fonction de la distance des flotteurs par rapport au capteur, et un fréquencemètre connecté au capteur de proximité pour déterminer la fréquence de résonance du circuit oscillant et pour fournir, à partir de cette mesure, une indication du coefficient de perméabilité du sot. To this end, this device for measuring the permeability of terrains and more particularly of very slightly permeable formations, of the double ring type, comprising two coaxial cylindrical rings sunk into the ground and containing respectively a central sheet of water contained in the inner ring and a ring of annular water contained in the space between your two rings, is characterized in that it comprises, at your upper part of the internal water, a proximity sensor forming part of a oscillating circuit, associated with a float floating on the surface of the central water layer and carrying an element modifying the resonance frequency of the oscillating circuit as a function of the distance of the floats from the sensor, and a frequency meter connected to the proximity sensor to determine the resonance frequency of the oscillating circuit and to provide, from this measurement, an indication of the coefficient of permeability of the fool.
On décrira ei-après,à titre d'exemple non Zimitatif, une forme d'exécution de ta présente invention,en référence au dessin annexé qui est une vue en coupe verticale schématique d'un infiltromètre à double anneau suivant l'invention. An embodiment of the present invention will be described hereinafter, by way of non-limiting example, with reference to the appended drawing which is a schematic vertical section view of a double ring infiltrometer according to the invention.
L'appareil de mesure de la perméabilité d'un sol 1 suivant l'invention est du type i double anneau, c'est-à- dire qu'il comporte deux anneaux cylindriques coaxiaux a savoir un anneau interne 2 et un anneau externe 3 ayant en général un diamètre interne double de celui de l'anneau interne 2 Ces anneaux sot munis à leur base de couteaux respectifs 2a et 3a permettant de les enfoncer dans le soZ l sur une profondeur d'une dizaine de centimètres environ. The apparatus for measuring the permeability of a soil 1 according to the invention is of the type i double ring, that is to say that it comprises two coaxial cylindrical rings, namely an internal ring 2 and an external ring 3 generally having an internal diameter twice that of the internal ring 2 These rings are provided at their base with respective knives 2a and 3a allowing them to be inserted into the soZ l to a depth of about ten centimeters.
Pour mesurer la perméabilité du sol 1 on déverse dans les anneaux 2 et 3 une certaine quantité d'eau de manière à constituer une lame d'eau centrale 4 et une lame d'eau annu- laire externe 5 ayant une épaisseur d'environ 5 cm à la surface du sol. On détermine suite la baisse procressive du niveau de la lame d'eau centrale 4, afin d'er. déduire le coefficient de perméabilité du soZ l. To measure the permeability of the soil 1, a certain amount of water is poured into the rings 2 and 3 so as to constitute a central water layer 4 and an external annular water layer 5 having a thickness of approximately 5 cm above the ground surface. The proactive drop in the level of the central water layer 4 is then determined in order to er. deduce the permeability coefficient of soZ l.
Suivant l'invention l'appareil de mesure comporte, à
la partie supérieure de l'anneau interne 2, un support 5 d'un capteur de proximité inductif (ou capacitif) 7 qui est associé à un flotteur 8 flottant à la surface de la lame d'eau centrale 4 et portant un élément modifiant la fréquence de résonance du circuit osciZZant en fonction de sa distance par rapport au capteur. Ce capteur fait partie d'un circuit oscillant dont la fréquence de résonance varie en fonction de la distance à laquelle se trouve le flotteur 8.According to the invention the measuring device comprises, at
the upper part of the internal ring 2, a support 5 of an inductive (or capacitive) proximity sensor 7 which is associated with a float 8 floating on the surface of the central water layer 4 and carrying an element modifying the resonance frequency of the osciZZant circuit as a function of its distance from the sensor. This sensor is part of an oscillating circuit whose resonant frequency varies as a function of the distance at which the float 8 is located.
La variation introduite par suite de la baisse du niveau de la lame d'eau centrale 4 peut être une variation d'induc- tance ou une variation de capacité. Le capteur inductif (ou capacitif) 7 est relié à un fréquencemètre 9 qui mesure en permanence la fréquence de résonance du circuit oscillant et qui permet de calculer, à partir de cette mesure, Ze coeffi- cient de perméabilité du sot 1. En fait la baisse du niveau de la Zame d'eau centrale 4 permet de déterminer le débit d'eau infiltré d'où résulte le coefficient de perméabilité.The variation introduced as a result of the drop in the level of the central water layer 4 can be a variation in inductance or a variation in capacity. The inductive (or capacitive) sensor 7 is connected to a frequency meter 9 which continuously measures the resonance frequency of the oscillating circuit and which makes it possible to calculate, on the basis of this measurement, the coefficient of permeability of the fool 1. In fact the drop in the level of the central water zone 4 makes it possible to determine the flow of infiltrated water from which the coefficient of permeability results.
Ce coefficient de perméabilité est proportionnel à la pente de la droite donnant la variation de la fréquence de résonance du circuit oscillant en fonction du temps.This coefficient of permeability is proportional to the slope of the line giving the variation of the resonance frequency of the oscillating circuit as a function of time.
L'appareil comporte avantageusement un thermomètre 10 qui est relié à une sonde thermique 11 plongeant dans la lame d'eau annulaire 5, afin de relever en permanence la température de l'eau et de permettre d'effectuer les corrections nécessaires. The apparatus advantageously comprises a thermometer 10 which is connected to a thermal probe 11 plunging into the annular water layer 5, in order to constantly raise the temperature of the water and allow the necessary corrections to be made.
Un enregistreur potentiomètrique 12, relié au fréquencemètre 9 et au thermomètre 10, permet d'enregistrer la fréquence et la température en continu. A potentiometric recorder 12, connected to the frequency meter 9 and to the thermometer 10, makes it possible to record the frequency and the temperature continuously.
De préférence l'ensemble des dut anneaux 2 et 3 est coiffé d'une caisse isolante thermiquement 12 -afin de prc- téter l'appareil à l'égard des vari-ations de la température ambiante. Preferably, all of the rings 2 and 3 are capped with a thermally insulating box 12-in order to protect the apparatus with regard to variations in ambient temperature.
L'appareiZ suivant l'invention permet de mesurer le coefficient de perméabilité de sols très faiblement perméables et la précision de mesure peut atteindre 1.10-9 m/s. The apparatus according to the invention makes it possible to measure the coefficient of permeability of very slightly permeable soils and the measurement accuracy can reach 1.10-9 m / s.
Dans une forme d'exécution non limitative de l'in- vention le diamètre de l'anneau intérieur 2 est de 125 mm et celui de l'anneau extérieur 3 de 320 mm. In a non-limiting embodiment of the invention, the diameter of the inner ring 2 is 125 mm and that of the outer ring 3 is 320 mm.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8500696A FR2576414B1 (en) | 1985-01-18 | 1985-01-18 | APPARATUS FOR MEASURING THE PERMEABILITY OF LANDS AND MORE PARTICULARLY VERY WEAKLY PERMEABLE FORMATIONS, OF THE DOUBLE RING TYPE |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8500696A FR2576414B1 (en) | 1985-01-18 | 1985-01-18 | APPARATUS FOR MEASURING THE PERMEABILITY OF LANDS AND MORE PARTICULARLY VERY WEAKLY PERMEABLE FORMATIONS, OF THE DOUBLE RING TYPE |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2576414A1 true FR2576414A1 (en) | 1986-07-25 |
| FR2576414B1 FR2576414B1 (en) | 1987-02-27 |
Family
ID=9315395
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8500696A Expired FR2576414B1 (en) | 1985-01-18 | 1985-01-18 | APPARATUS FOR MEASURING THE PERMEABILITY OF LANDS AND MORE PARTICULARLY VERY WEAKLY PERMEABLE FORMATIONS, OF THE DOUBLE RING TYPE |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2576414B1 (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4956993A (en) * | 1989-04-25 | 1990-09-18 | Marathon Oil Company | Soil infiltrometer |
| FR2754060A1 (en) * | 1996-09-27 | 1998-04-03 | Horizons | System for in situ measurement of hydraulic conductivity of low permeable ground for accommodating household waste |
| FR2800165A1 (en) * | 1999-10-20 | 2001-04-27 | Eaux De Marseille | Soil permeability measurement unit has tube cavity inserted in soil is easy and accurate to use |
| CN107870143A (en) * | 2017-10-31 | 2018-04-03 | 中煤科工集团西安研究院有限公司 | A kind of field simply automatic double-ring infiltration tester and method |
| CN108226001A (en) * | 2017-11-30 | 2018-06-29 | 成都理工大学 | A kind of bicyclic method automatic test device and bicyclic water injection test method |
| CN108254300A (en) * | 2017-12-13 | 2018-07-06 | 西北农林科技大学 | A kind of device and method for measuring pervious surface infiltration rate |
| CN109342290A (en) * | 2018-11-09 | 2019-02-15 | 北京建筑大学 | A device for measuring permeability coefficient of permeable pavement |
| CN110031380A (en) * | 2019-05-21 | 2019-07-19 | 科利尔环保科技有限责任公司 | A kind of method of scene nondestructive measurement celluar concrete infiltration rate |
| CN112326525A (en) * | 2020-10-23 | 2021-02-05 | 山东大学 | A double-ring water seepage experimental device and method |
| CN113155706A (en) * | 2021-05-19 | 2021-07-23 | 山东省水利科学研究院 | Method for determining permeability coefficient of unsaturated unconsolidated rock stratum in aeration zone by using field soil |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH380039A (en) * | 1960-06-01 | 1964-07-15 | Soletanche S A R L | Apparatus for measuring the permeability of a soil and method of activating this apparatus |
| FR2127151A5 (en) * | 1971-02-25 | 1972-10-13 | Louis Claude | |
| US3861196A (en) * | 1972-07-03 | 1975-01-21 | Domenico Domenighetti | Apparatus for measuring in situ the permeability of a civil engineering working stratum |
| US4341110A (en) * | 1980-06-19 | 1982-07-27 | Block Philip M | Percolation testing method and apparatus |
-
1985
- 1985-01-18 FR FR8500696A patent/FR2576414B1/en not_active Expired
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH380039A (en) * | 1960-06-01 | 1964-07-15 | Soletanche S A R L | Apparatus for measuring the permeability of a soil and method of activating this apparatus |
| FR2127151A5 (en) * | 1971-02-25 | 1972-10-13 | Louis Claude | |
| US3861196A (en) * | 1972-07-03 | 1975-01-21 | Domenico Domenighetti | Apparatus for measuring in situ the permeability of a civil engineering working stratum |
| US4341110A (en) * | 1980-06-19 | 1982-07-27 | Block Philip M | Percolation testing method and apparatus |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4956993A (en) * | 1989-04-25 | 1990-09-18 | Marathon Oil Company | Soil infiltrometer |
| FR2754060A1 (en) * | 1996-09-27 | 1998-04-03 | Horizons | System for in situ measurement of hydraulic conductivity of low permeable ground for accommodating household waste |
| FR2800165A1 (en) * | 1999-10-20 | 2001-04-27 | Eaux De Marseille | Soil permeability measurement unit has tube cavity inserted in soil is easy and accurate to use |
| CN107870143A (en) * | 2017-10-31 | 2018-04-03 | 中煤科工集团西安研究院有限公司 | A kind of field simply automatic double-ring infiltration tester and method |
| CN108226001A (en) * | 2017-11-30 | 2018-06-29 | 成都理工大学 | A kind of bicyclic method automatic test device and bicyclic water injection test method |
| CN108226001B (en) * | 2017-11-30 | 2020-04-24 | 成都理工大学 | Double-ring water injection test method |
| CN108254300A (en) * | 2017-12-13 | 2018-07-06 | 西北农林科技大学 | A kind of device and method for measuring pervious surface infiltration rate |
| CN109342290A (en) * | 2018-11-09 | 2019-02-15 | 北京建筑大学 | A device for measuring permeability coefficient of permeable pavement |
| CN110031380A (en) * | 2019-05-21 | 2019-07-19 | 科利尔环保科技有限责任公司 | A kind of method of scene nondestructive measurement celluar concrete infiltration rate |
| CN112326525A (en) * | 2020-10-23 | 2021-02-05 | 山东大学 | A double-ring water seepage experimental device and method |
| CN113155706A (en) * | 2021-05-19 | 2021-07-23 | 山东省水利科学研究院 | Method for determining permeability coefficient of unsaturated unconsolidated rock stratum in aeration zone by using field soil |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2576414B1 (en) | 1987-02-27 |
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