FR2468694A1 - Piezoelectric vehicle counting sensor cable - is surrounded by rubberised resin in channel across concrete roadway and avoids problem of multiple detectors - Google Patents
Piezoelectric vehicle counting sensor cable - is surrounded by rubberised resin in channel across concrete roadway and avoids problem of multiple detectors Download PDFInfo
- Publication number
- FR2468694A1 FR2468694A1 FR7927012A FR7927012A FR2468694A1 FR 2468694 A1 FR2468694 A1 FR 2468694A1 FR 7927012 A FR7927012 A FR 7927012A FR 7927012 A FR7927012 A FR 7927012A FR 2468694 A1 FR2468694 A1 FR 2468694A1
- Authority
- FR
- France
- Prior art keywords
- resin
- sensor
- groove
- coated
- channel
- 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.)
- Pending
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01F—ADDITIONAL WORK, SUCH AS EQUIPPING ROADS OR THE CONSTRUCTION OF PLATFORMS, HELICOPTER LANDING STAGES, SIGNS, SNOW FENCES, OR THE LIKE
- E01F11/00—Road engineering aspects of Embedding pads or other sensitive devices in paving or other road surfaces, e.g. traffic detectors, vehicle-operated pressure-sensitive actuators, devices for monitoring atmospheric or road conditions
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C23/00—Auxiliary devices or arrangements for constructing, repairing, reconditioning, or taking-up road or like surfaces
- E01C23/06—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road
- E01C23/09—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for forming cuts, grooves, or recesses, e.g. for making joints or channels for markings, for cutting-out sections to be removed; for cleaning, treating, or filling cuts, grooves, recesses, or fissures; for trimming paving edges
- E01C23/0966—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for forming cuts, grooves, or recesses, e.g. for making joints or channels for markings, for cutting-out sections to be removed; for cleaning, treating, or filling cuts, grooves, recesses, or fissures; for trimming paving edges for filling or priming, with or without working the surface of the filling or applying particulate material thereto, e.g. for filling the joints of stone-sett paving
- E01C23/0986—Devices or arrangements for working the finished surface; Devices for repairing or reconditioning the surface of damaged paving; Recycling in place or on the road for forming cuts, grooves, or recesses, e.g. for making joints or channels for markings, for cutting-out sections to be removed; for cleaning, treating, or filling cuts, grooves, recesses, or fissures; for trimming paving edges for filling or priming, with or without working the surface of the filling or applying particulate material thereto, e.g. for filling the joints of stone-sett paving with preformed elements, e.g. joint strips
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/01—Detecting movement of traffic to be counted or controlled
Landscapes
- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Mining & Mineral Resources (AREA)
- Road Signs Or Road Markings (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
Description
La présente invention concerne une installation de détection de passage d'objets pesants comportant un capteur piézo-électrique inséré dans une chaussée. The present invention relates to an installation for detecting the passage of heavy objects comprising a piezoelectric sensor inserted in a roadway.
L'invention s'applique spécialement pour le comptage d'essieux de véhicules sur routes. On connait des dispositifs de comptage d'essieux constitués par des capteurs pneumatiques ou électriques disposés à la surface en travers de la chaussée, cependant de tels capteurs disposés directement sur la chaussée risquent de se détériorer ou d'être arrachés notamment dans les régions enneigées lors de passages de chasses-neige. On a alors utilisé des capteurs piézoélectriques disposés dans la chaussée mais si le fonctionnement est satisfaisant dans le cas de chaussées en asphalte, il n'en est pas de même avec les chaussées en béton. En effet, les chaussées en béton comportent des joints et le passage des roues de véhicule sur ces joints provoque une onde de pression qui se propage jusqu'au capteur qui la détecte et il en résulte que chaque essieu de véhicule est compté plusieurs fois. The invention is especially applicable for counting axles of vehicles on roads. Axle counting devices are known which consist of pneumatic or electric sensors placed on the surface across the road, however such sensors placed directly on the road are liable to deteriorate or be torn off, particularly in snow-covered regions during snow plow passages. Piezoelectric sensors placed in the road were then used, but if the operation is satisfactory in the case of asphalt pavements, it is not the same with concrete pavements. Indeed, concrete pavements have seals and the passage of the vehicle wheels over these seals causes a pressure wave which propagates to the sensor which detects it and it follows that each vehicle axle is counted several times.
La présente invention a pour but de pallier ces inconvénients et a pour objet une installation de détection de passage d'objets pesants comportant un capteur piézo-électrique inséré dans une chaussée caractérisée en ce que le capteur est placé dans une saignée de ladite chaussée, les parois de ladite saignée étant revêtues d'une couche d'accrochage, et en ce qu'entre cette couche et le capteur sont situés une première résine enrobant entièrement le capteur puis un mélange de résine caoutchoutée remplissant l'espace entre la résine d'enrobage et la couche d'accrochage appliquée contre les parois de la saignée, ladite résine caoutchoutée dépassant légèrement le niveau de la chaussée. The object of the present invention is to overcome these drawbacks and relates to an installation for detecting the passage of heavy objects comprising a piezoelectric sensor inserted in a roadway, characterized in that the sensor is placed in a groove in said roadway, the walls of said groove being coated with a bonding layer, and in that between this layer and the sensor are located a first resin completely coating the sensor then a mixture of rubberized resin filling the space between the coating resin and the bonding layer applied against the walls of the groove, said rubberized resin slightly exceeding the level of the roadway.
L'invention a aussi pour objet un procédé de réalisation d'une installation de détection de passage d'objets pesants caractérisé par les opérations suivantes - On place des cavaliers de centrage autour du capteur. The subject of the invention is also a method for producing a installation for detecting the passage of heavy objects, characterized by the following operations - Centering jumpers are placed around the sensor.
- On place le capteur avec ses cavaliers dans un moule long et étroit.- The sensor is placed with its jumpers in a long and narrow mold.
- On verse dans le moule, dont les parois ont été préalablement graissées, un mélange de résine avec son durcisseur.- A mixture of resin and its hardener is poured into the mold, the walls of which have been previously greased.
- Lorsque l'ensemble est polymérisé, on démoule, on nettoie le capteur enrobé obtenu et on réalise un chanfrein le long des deux bordssuperieurs longitudinaux de l'ensemble.- When the assembly is polymerized, it is removed from the mold, the coated sensor obtained is cleaned and a chamfer is produced along the two longitudinal upper edges of the assembly.
- On dispose sur les parois d'une saignée transversale réalisée dans la chaussée une couche d'accrochage constituée d'un mélange de résine, de son durcisseur et de sable fin.- There is on the walls of a transverse groove made in the floor a bonding layer consisting of a mixture of resin, its hardener and fine sand.
- On place le capteur enrobé dans la saignée en le posant sur des étriers suspendus à des tiges traversant la saignée.- The coated sensor is placed in the groove by placing it on stirrups suspended from rods crossing the groove.
- On coule entre la saignée et le capteur enrobé un mélange homogène de résine caoutchoutée avec durcisseur.- A homogeneous mixture of rubberized resin with hardener is poured between the bleed and the sensor coated.
- Une fois la résine polymérisée, on retire les tiges et on coupe les- extrémités des étriers.- Once the resin has polymerized, the rods are removed and the ends of the stirrups are cut.
- On couvre le capteur enrobé d'une couche de mélange de résine caoutchoutée avec durcisseur, ladite couche débordant sur les "rives" de la saignée en s'amincissant petit à petit.- We cover the sensor coated with a layer of rubberized resin mixture with hardener, said layer overflowing on the "edges" of the groove gradually thinning.
L'invention sera bien comprise à la lumière de la description d'un exemple de réalisation de l'invention faite ci-après en regard du dessin annexé dans lequel
La figure 1 montre un capteur piézo-électrique sous forme de câble.The invention will be clearly understood in the light of the description of an exemplary embodiment of the invention given below with reference to the appended drawing in which
Figure 1 shows a piezoelectric sensor in the form of a cable.
La figure 2 montre un moule pour la réalisation de l'installation selon l'invention. FIG. 2 shows a mold for producing the installation according to the invention.
La figure 3 montre en coupe un capteur enrobé. Figure 3 shows in section a coated sensor.
La figure 4 montre une étape du procédé d'une installation de détection de passage d'objets pesants selon l'invention. FIG. 4 shows a step in the method of an installation for detecting the passage of heavy objects according to the invention.
La figure 5 donne une représentation en coupe de l'installation terminée. Figure 5 gives a sectional representation of the completed installation.
On utilise comme capteur de pression un capteur piézo-électrique se présentant sous la forme d'un câble blindé flexible dont l'amie et la gaine métalliques sont isolées l'une de l'autre par une céramique piézo-électrique. Un tel détecteur est connu et ne fait pas partie de l'invention qui consiste seulement dans son installation dans une chaussée de manière que le capteur ne soit sensible qu'aux pressions s'exerçant directement sur l'installation mais insensible aux pressions provenant d'ondes de pression dont l'origine est plus ou moins éloignée de l'installation et transmises à cette installation par la chaussée. A piezoelectric sensor is used as the pressure sensor in the form of a flexible shielded cable whose metal friend and sheath are isolated from each other by a piezoelectric ceramic. Such a detector is known and does not form part of the invention which consists only in its installation in a roadway so that the sensor is sensitive only to the pressures exerted directly on the installation but insensitive to the pressures coming from pressure waves whose origin is more or less distant from the installation and transmitted to this installation by the roadway.
La figure 1 montre donc un capteur 1 sur lequel ont été placés des cavaliers 2, constitués par exemple par des petits morceaux de fil de fer. Ces cavaliers 2 ont pour but de centrer le capteur 1 dans un moule 3, figure 2, afin d'enrober le capteur 1 d'une résine. FIG. 1 therefore shows a sensor 1 on which jumpers 2 have been placed, constituted for example by small pieces of wire. The purpose of these jumpers 2 is to center the sensor 1 in a mold 3, FIG. 2, in order to coat the sensor 1 with a resin.
Afin de permettre le démoulage ultérieur du capteur une fois la résine polymérisée, on graisse le moule 3 avant de couler la résine. In order to allow the release of the sensor from the mold after the resin has polymerized, the mold 3 is greased before pouring the resin.
Après le démoulage, on obtient un capteur enrobé 5 tel que représenté en coupe figure 3 dans lequel on retrouve le capteur 1, les cavaliers de centrage, tel que celui 2, représenté sur la coupe et la résine 4 entourant le capteur. De chaque côté des bords supérieurs longitudinaux du capteur enrobé, on a réalisé un chanfrein 6. After demolding, a coated sensor 5 is obtained as shown in section in FIG. 3 in which there is the sensor 1, the centering jumpers, such as that 2, shown in the section and the resin 4 surrounding the sensor. On each side of the longitudinal upper edges of the coated sensor, a chamfer 6 has been produced.
Le capteur enrobé 5 mesure par exemple 3 mètres de long et a une section de 2 cm x 2 cm. La résine utilisée est une résine procurant une dureté d'environ 770 shore D après polymérisation.The coated sensor 5 measures for example 3 meters long and has a section of 2 cm x 2 cm. The resin used is a resin providing a hardness of approximately 770 shore D after polymerization.
On réalise alors en travers de la route, dans une chaussée en béton par exemple puisque c'est particulièrement dans le cas de ces chaussées en béton qu'il se produit, au passage des joints par les véhicules, des ondes de pression qui se propagent jusqu'au capteur, une saignée de quatre centimètres de large sur trois centimètres de profondeur. On nettoie la saignée et on dispose sur les parois de cette saignée une couche d'accrochage 7, figure 4, constituée d'un mélange de résine, de durcisseur et de sable fin. La résine utilisée est la même que la précédente. On place alors le capteur enrobé 5 dans la saignée en le posant sur des étriers tels que 8, constitués par exemple par des fils de fer suspendus à des tiges telles que 9. On verse ensuite un mélange de résine caoutchoutée 11 avec durcisseur entre le capteur enrobé 5 et les parois de la saignée. One then realizes across the road, in a concrete pavement for example since it is particularly in the case of these concrete pavements that occurs, with the passage of joints by vehicles, pressure waves which propagate up to the sensor, a groove four centimeters wide by three centimeters deep. The groove is cleaned and there is a bonding layer 7, FIG. 4, on the walls of this groove, consisting of a mixture of resin, hardener and fine sand. The resin used is the same as the previous one. The coated sensor 5 is then placed in the groove by placing it on stirrups such as 8, constituted for example by wires suspended from rods such as 9. Then a mixture of rubberized resin 11 with hardener is poured between the sensor coated 5 and the walls of the groove.
La dureté de cette résine caoutchoutée est d'environ 600 shore A.The hardness of this rubberized resin is around 600 shore A.
Sur la figure 4, on a représenté un récipient verseur 10 pour illustrer cette étape du procédé.In Figure 4, there is shown a pouring container 10 to illustrate this step of the process.
Une fois la résine polymérisée, on coupe les extrémités des fils 8 et on retire les tiges 9. On coule- alors la meme résine 11 que précédemment c'est-à-dire un mélange de résine caoutchoutée avec un durcisseur sur toute la saignée par dessus le capteur enrobé 5 en débordant largement -sur les "rives" de la saignée, la couche s'amincissant -petit à petit sur ces rives mais en ne laissant que quelques millimètres au-dessus du capteur. On obtient alors l'installation représentée figure 5. Once the resin has polymerized, the ends of the wires 8 are cut and the rods 9 are removed. Then the same resin 11 is poured as above, that is to say a mixture of rubberized resin with a hardener over the whole of the groove. above the coated sensor 5, extending widely over the "edges" of the groove, the layer thinning-little by little on these edges but leaving only a few millimeters above the sensor. The installation shown in FIG. 5 is then obtained.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7927012A FR2468694A1 (en) | 1979-10-31 | 1979-10-31 | Piezoelectric vehicle counting sensor cable - is surrounded by rubberised resin in channel across concrete roadway and avoids problem of multiple detectors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7927012A FR2468694A1 (en) | 1979-10-31 | 1979-10-31 | Piezoelectric vehicle counting sensor cable - is surrounded by rubberised resin in channel across concrete roadway and avoids problem of multiple detectors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| FR2468694A1 true FR2468694A1 (en) | 1981-05-08 |
Family
ID=9231234
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR7927012A Pending FR2468694A1 (en) | 1979-10-31 | 1979-10-31 | Piezoelectric vehicle counting sensor cable - is surrounded by rubberised resin in channel across concrete roadway and avoids problem of multiple detectors |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2468694A1 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2482340A1 (en) * | 1980-05-08 | 1981-11-13 | Electronique Controle Mesure S | Underground piezoelectric traffic counter cable - uses piezoelectric cable laid in u=shape to both count and detect direction of passing vehicles on road |
| EP0358390A2 (en) * | 1988-09-07 | 1990-03-14 | Ngk Spark Plug Co., Ltd. | Piezoelectric transducer |
| FR2642775A1 (en) * | 1989-02-09 | 1990-08-10 | Electronique Controle Mesure S | DEVICE FOR DETECTING THE PASSAGE OF VEHICLES ON A PIEZOELECTRIC FILM PAVEMENT |
| FR2700345A1 (en) * | 1993-01-12 | 1994-07-13 | Lafarge Nouveaux Materiaux | A method of constructing a soil incorporating a wire as a guidewire and accessory for precise placement of the wire under the ground level. |
| EP0620321A1 (en) * | 1993-04-01 | 1994-10-19 | ETAT FRANCAIS Représenté par le Ministère de l'Equipement, du Logement, des Transports et de l'Espace | Process of manufacturing a road traffic sensor and sensor for installing across the road |
| CN105466657A (en) * | 2016-02-03 | 2016-04-06 | 吉林大学 | Piezoelectric double-cross beam vehicle vibration detection device based on ground |
| CN111119000A (en) * | 2020-01-14 | 2020-05-08 | 辽宁金洋集团信息技术有限公司 | Asphalt pavement paving structure with strip-shaped weighing sensors |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB266016A (en) * | 1925-10-13 | 1927-02-14 | Thomas Barker Ross | Improvements in road signalling devices |
| US3105952A (en) * | 1960-08-04 | 1963-10-01 | Kidder Warren Benjamin | Pressure detecting method and apparatus |
| GB1209506A (en) * | 1968-03-18 | 1970-10-21 | Marconi Co Ltd | Improvements in or relating to vibration detectors |
| FR2233615A1 (en) * | 1973-06-12 | 1975-01-10 | Gen Dynamics Corp | |
| US3911390A (en) * | 1973-11-07 | 1975-10-07 | Richard H Myers | Traffic sensor strip |
| FR2373784A1 (en) * | 1976-12-09 | 1978-07-07 | Marconi Co Ltd | PRESSURE DETECTION DEVICE |
| GB2003635A (en) * | 1977-07-16 | 1979-03-14 | Plessey Co Ltd | Vehicle presence detector |
-
1979
- 1979-10-31 FR FR7927012A patent/FR2468694A1/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB266016A (en) * | 1925-10-13 | 1927-02-14 | Thomas Barker Ross | Improvements in road signalling devices |
| US3105952A (en) * | 1960-08-04 | 1963-10-01 | Kidder Warren Benjamin | Pressure detecting method and apparatus |
| GB1209506A (en) * | 1968-03-18 | 1970-10-21 | Marconi Co Ltd | Improvements in or relating to vibration detectors |
| FR2233615A1 (en) * | 1973-06-12 | 1975-01-10 | Gen Dynamics Corp | |
| US3911390A (en) * | 1973-11-07 | 1975-10-07 | Richard H Myers | Traffic sensor strip |
| FR2373784A1 (en) * | 1976-12-09 | 1978-07-07 | Marconi Co Ltd | PRESSURE DETECTION DEVICE |
| GB2003635A (en) * | 1977-07-16 | 1979-03-14 | Plessey Co Ltd | Vehicle presence detector |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2482340A1 (en) * | 1980-05-08 | 1981-11-13 | Electronique Controle Mesure S | Underground piezoelectric traffic counter cable - uses piezoelectric cable laid in u=shape to both count and detect direction of passing vehicles on road |
| EP0358390A2 (en) * | 1988-09-07 | 1990-03-14 | Ngk Spark Plug Co., Ltd. | Piezoelectric transducer |
| EP0358390A3 (en) * | 1988-09-07 | 1991-05-22 | Ngk Spark Plug Co., Ltd. | Piezoelectric transducer |
| FR2642775A1 (en) * | 1989-02-09 | 1990-08-10 | Electronique Controle Mesure S | DEVICE FOR DETECTING THE PASSAGE OF VEHICLES ON A PIEZOELECTRIC FILM PAVEMENT |
| EP0384874A2 (en) * | 1989-02-09 | 1990-08-29 | Electronique Controle Mesure | Device for the detection of passing vehicles on a road with a piezoelectric film |
| EP0384874A3 (en) * | 1989-02-09 | 1990-10-03 | Electronique Controle Mesure | Device for the detection of passing vehicles on a road with a piezoelectric film |
| FR2700345A1 (en) * | 1993-01-12 | 1994-07-13 | Lafarge Nouveaux Materiaux | A method of constructing a soil incorporating a wire as a guidewire and accessory for precise placement of the wire under the ground level. |
| WO1994016151A1 (en) * | 1993-01-12 | 1994-07-21 | Lafarge Nouveaux Materiaux (S.A.) | Method for building a floor with a built-in wire such as a guide wire, and accessory for accurately positioning the wire beneath the floor |
| EP0620321A1 (en) * | 1993-04-01 | 1994-10-19 | ETAT FRANCAIS Représenté par le Ministère de l'Equipement, du Logement, des Transports et de l'Espace | Process of manufacturing a road traffic sensor and sensor for installing across the road |
| CN105466657A (en) * | 2016-02-03 | 2016-04-06 | 吉林大学 | Piezoelectric double-cross beam vehicle vibration detection device based on ground |
| CN111119000A (en) * | 2020-01-14 | 2020-05-08 | 辽宁金洋集团信息技术有限公司 | Asphalt pavement paving structure with strip-shaped weighing sensors |
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