SENSOR ARRANGEMENT FOR INSTALLATION IN A CARRIAGEWAY AND PROCESS OF INSTALLING THIS SENSOR ARRANGEMENT IN A CARRIAGEWAY
20200096382 ยท 2020-03-26
Inventors
Cpc classification
International classification
Abstract
A sensor arrangement for installation in a carriageway includes a piezoelectric measuring arrangement disposed in a cavity of a hollow profile and in mechanical contact with the hollow profile. The hollow profile includes an external force introduction surface, which is configured to transmit a weight force onto the piezoelectric measuring arrangement, which outputs electrical signals proportional to a magnitude of the weight force. The sensor arrangement includes a separating element, which is configured to prevent a rolling force acting on the separating element from being transmitted into the hollow profile. The separating element includes at least one distribution opening configured to permit grout to flow through the distribution opening.
Claims
1. A sensor arrangement for installation in a carriageway, the sensor arrangement comprising: a hollow profile and a piezoelectric measuring arrangement; said hollow profile defining a cavity and said piezoelectric measuring arrangement being arranged in the cavity in mechanical contact with the hollow profile; wherein the hollow profile includes a force introduction flange that defines an external force introduction surface and is configured and disposed to transmit a weight force acting on the force introduction surface onto the piezoelectric measuring arrangement; and wherein the piezoelectric measuring arrangement is configured to detect an introduced weight force and configured to output electrical signals that are proportional to a magnitude of the detected weight force; a first separating element that is configured to prevent a rolling force acting on the separating element from being transmitted into the hollow profile, and wherein the first separating element defines a distribution opening that is configured to permit grout to flow through said distribution opening.
2. The sensor arrangement according to claim 1, wherein the first separating element has a low bulk modulus and a low elastic modulus and is configured and disposed to prevent rolling forces propagating in a transverse direction perpendicular to the vertical plane from being transmitted to the hollow profile.
3. The sensor arrangement according to any of claim 1, wherein the first separating element defines a lower end that is configured and disposed to delimit the first separating element in the vertical plane; wherein the first separating element defines an upper end that is configured and disposed to delimit the first separating element in the vertical plane; wherein the distribution opening is arranged between said lower end and said upper end; and wherein the distribution opening is arranged within 20 mm of the force introduction surface.
4. The sensor arrangement according to claim 1, further comprising a second separating element; wherein the hollow profile defines a first external attachment surface and a second external attachment surface; wherein the first separating element is attached to the first external attachment surface; wherein the second separating element is attached to the second attachment surface; wherein the first separating element is installed in the carriageway in front of the hollow profile as seen in the direction of travel; and wherein the second separating element is installed in the carriageway behind the hollow profile as seen in the direction of travel.
5. The sensor arrangement according to claim 4, wherein the first separating element is mounted outwardly on the first external attachment surface and the second separating element mounted outwardly on the second external attachment surface.
6. The sensor arrangement according to claim 4, wherein the first separating element defines a lower end that delimits the first separating element in the vertical plane; wherein the first separating element is arranged against the force introduction flange that defines the force introduction surface by said lower end.
7. The sensor arrangement according to claim 4 wherein the first separating element defines a first lower end that delimits the separating element in the vertical plane; wherein the first separating element is attached by the first lower end to the force introduction flange in front of the hollow profile as seen in the direction of travel; and wherein the second separating element is attached by a second lower end to the force introduction flange behind the hollow profile as seen in the direction of travel.
8. The sensor arrangement according to claim 7, wherein the first separating element is mounted outwardly on the force introduction flange.
9. The sensor arrangement according to claim 7, further comprising: a first insulating foam part and a second insulating foam part: wherein the hollow profile defines a first external attachment surface; wherein the first insulating foam part being attached to a first attachment surface in front of the hollow profile as seen in the direction of travel; wherein the second insulating foam part being attached to a second attachment surface behind the hollow profile as seen in the direction of travel; wherein the first separating element abuts on the first insulating foam part with its first lower end; and wherein the second separating element abuts on the second insulating foam part with its second lower end.
10. A process for installing a sensor arrangement in a carriageway; wherein the sensor arrangement comprises a hollow profile and a piezoelectric measuring arrangement; said hollow profile comprising a cavity and said piezoelectric measuring arrangement being arranged in said cavity in mechanical contact with the hollow profile; wherein the hollow profile comprises an external force introduction surface and the hollow profile transmits a weight force acting on said force introduction surface onto the piezoelectric measuring arrangement; wherein the piezoelectric measuring arrangement detects an introduced weight force and outputs electrical signals that are proportional to a magnitude of the detected weight force; the process comprising the steps of: forming an empty groove in a pavement (6) of the carriageway having such dimensions that it can completely accommodate the sensor arrangement therein and space for grout around the sensor arrangement; inserting the sensor arrangement in the groove; and casting grout in the space provided for grout so that grout flows through a distribution opening in a separating element that prevents a rolling force acting on the separating element from being transmitted into the hollow profile and the grout becomes distributed in the space provided for grout.
11. The process according to claim 10, wherein the sensor arrangement is inserted in the empty groove when the empty groove has become partially filled with grout; and the sensor arrangement is positioned in the grout so that a force anchoring flange of the sensor arrangement becomes surrounded by grout.
12. The process according to claim 10, wherein the separating element comprises an upper end that delimits the separating element in a vertical plane and the sensor arrangement is positioned in the groove so that the upper end is flush with the carriageway surface level; and the sensor arrangement is anchored in this position in the groove by the curing of the grout that surrounds the force anchoring flange.
13. The process according to claim 10, wherein the space provided for grout is defined by an upper space located between the force introduction surface and the carriageway surface level and at least one lateral space located between the separating element and a lateral surface of the groove; and the groove is completely filled with grout so that the upper space is completely filled with grout and the lateral space is completely filled with grout.
14. The process according to claim 13, wherein the grout when it is introduced into the groove is distributed by means of the distribution opening in the upper space and in the lateral space.
15. A sensor arrangement installed in a carriageway by using the process according to claim 13, the sensor arrangement comprising: a hollow profile defining a cavity and an external force introduction surface; a piezoelectric measuring arrangement arranged in the cavity in mechanical contact with the hollow profile; wherein the hollow profile is configured and to transmit a weight force acting on the force introduction surface onto the piezoelectric measuring arrangement; wherein the piezoelectric measuring arrangement is configured to detect an introduced weight force and configured to output electrical signals that are proportional to a magnitude of the detected weight force; a first separating element that is configured to prevent a rolling force acting on the separating element from being transmitted into the hollow profile, wherein the first separating element defines a distribution opening that is configured to permit grout to flow through said distribution opening; and wherein the cured grout is material-bonded to the force introduction surface in the upper space; and cured grout in the distribution opening integrally connects cured grout in the upper space to cured grout in the lateral space.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In the following the invention will be explained by way of example with reference to the figures in which
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[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
[0022]
DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION
[0023]
[0024] Sensor arrangement 1 comprises a hollow profile 2, a piezoelectric measuring arrangement 3 and at least one separating element 4, 4, 4.
[0025] The hollow profile 2 comprises a force introduction flange 20, a tubular member 21 and a force anchoring flange 22, Hollow profile 2 is made of mechanically resistant material such as pure metals, aluminum alloys, nickel alloys, cobalt alloys, iron alloys, etc. The force introduction flange 20 and force anchoring flange 22 are T-shaped as seen along a section in the transverse plane. The tubular part 21 is circular as seen along a section in the transverse plane. The hollow profile 2 is preferably mirror-symmetrical with respect to a vertical plane placed in the center of the hollow profile 2. Preferably, the force introduction flange 20, tubular part 21 and force anchoring flange 22 are made of one piece.
[0026] Tubular part 21 is arranged between the force introduction flange 20 and the force anchoring flange 22. A center of the hollow profile 2 coincides with the center of the tubular part 21. The center refers to a geometric center.
[0027] The force introduction flange 20 and force anchoring flange 22 are designed as compact and very stiff members. A weight force to be detected of traveling vehicles acts along the vertical direction V onto the force introduction surface 200. The weight force to be detected is transmitted by the force introduction flange 20 into the tubular part 21 along the vertical direction V. Anchoring 220 serves to anchor the hollow profile 2 in a grout in a groove of the carriageway.
[0028] As shown in
[0029] The force anchoring flange 22 begins in a transition region that connects to the tubular part 21 and ends at an anchoring 220. Anchoring 220 is plate-shaped and extends in the longitudinal plane. In the installed state shown in
[0030] The piezoelectric measuring arrangement 3 is arranged in the center of the tubular part 21. The piezoelectric measuring arrangement 3 comprises a plurality of piezoelectric elements. The piezoelectric elements are disc-shaped and are made of piezoelectric crystal material such as quartz (SiO.sub.2 single crystal), calcium gallo-germanate (Ca.sub.3Ga.sub.2Ge.sub.4O.sub.14 or CGG), langasite (La.sub.3Ga.sub.5SiO.sub.10 or LGS), tourmaline, gallium orthophosphate, piezoceramics, etc. The crystallographic orientation of the piezoelectric elements is such that they have a high sensitivity for the weight force to be detected. Preferably, the orientation of the piezoelectric elements is such that negative and positive electrical polarization charges are generated on those surfaces on which the weight force acts along the vertical direction V. The number of the electrical polarization charges is proportional to the magnitude of the detected weight force. The electrical polarization charges are received as electrical signals by electrodes and are transmitted by electrical conductors to an evaluation unit (not shown) where they are evaluated.
[0031] Preferably, the piezoelectric measuring arrangement 3 comprises a plurality of piezoelectric elements arranged at a distance of 50 mm to 100 mm from one another along the longitudinal axis L on a ruler. The ruler carrying the piezoelectric elements is pushed into a central cavity of the tubular part 21. The dimension of the piezoelectric measuring arrangement 3 is slightly smaller in the vertical direction V than that of the cavity. The tubular part 21 has a thin-walled and elastic design. Thus, in preparing to install the piezoelectric measuring arrangement 3 into the central cavity of the tubular part 21, the tubular part 21 may be bent open in the vertical direction V by pressing to the sides in and against the transverse direction Q, and then the ruler together with the piezoelectric elements is pushed into the cavity in the longitudinal direction L. Upon termination of the lateral pressing, the piezoelectric measuring arrangement 3 is held in the cavity under a mechanical prestress. The mechanical prestressing is in and against the vertical direction V. Thus, the piezoelectrical measuring arrangement 3 is in mechanical contact to the hollow profile 2. A force shunt across the thin walls of the tubular part 21 is small. A majority of the weight force to be detected is transmitted by the force introduction flange 20 into the piezoelectric measuring arrangement 3 arranged in the central cavity of the tubular part 21.
[0032] The separating element 4, 4, 4 is made of material with low bulk modulus and low elastic modulus such as silicone foam, rubber, expanded polypropylene (EPP), ethylene-propylene-diene rubber (EPDM), etc. Preferably, the length of the separating element 4, 4, 4 in the longitudinal direction L is identical to that of the hollow profile 2.
[0033] In the first embodiment of a sensor arrangement 1 according to
[0034] Preferably, in the first embodiment of a sensor arrangement 1 according to
[0035] In the first embodiment of a sensor arrangement 1 according to
[0036] In the second embodiment of a sensor arrangement 1 according to
[0037] In the second embodiment of a sensor arrangement 1 according to
[0038] In the second embodiment of a sensor arrangement 1 according to
[0039] The second embodiment of a sensor arrangement 1 according to
[0040] Rolling forces are generated when the carriageway is deflected due to the weight of vehicles traveling on the carriageway. The rolling forces propagate in the direction of travel, they act ahead of the moving vehicles in the direction of travel and they act behind the vehicles. The magnitude of the rolling forces decreases below the carriageway surface with increasing distance from the carriageway surface. Due to the low bulk modulus and low elastic modulus of the separating element 4, 4, 4, the separating element 4, 4, 4 is deformed by the action of the rolling forces and the propagating rolling forces are not introduced into the hollow profile 2. This is also called rolling force decoupling. Thus, the separating element 4, 4, 4 effectively prevents the introduction of rolling forces into the hollow profile 2.
[0041] The separating element 4, 4, 4 defines at least one distribution opening 40, 40 wherein grout can flow through said distribution opening 40, 40. In the embodiments according to
[0042] The separating element 4, 4, 4 defines at least one upper end 42, 42. Upper end 42, 42 delimits the separating element 4, 4, 4 in the vertical plane. Upper end 42, 42 is located above the force introduction surface 200 as seen in the vertical direction V. The separating element 4, 4, 4 is delimited by a first upper end 42 above the force introduction surface 200 in front of the hollow profile 2 as seen in the direction of travel. Separating element 4, 4, 4 is delimited by a second upper end 42 above the force introduction surface 200 behind the hollow profile 2 as seen in the direction of travel. The upper end 42, 42 extends in the longitudinal direction L substantially parallel to the force introduction surface 200. The distribution opening 40, 40 is arranged between the lower end 41, 41 and the upper end 42, 42. Preferably, a plurality of distribution openings 40, 40 are arranged in a row in the separating element 4, 4, 4. Preferably, the distribution opening 40, 40 is located centrally between the lower end 41, 41 and the upper end 42, 42. Distribution opening 40, 40 is preferably arranged close to the force introduction surface 200. A position of the distribution opening 40, 40 close to the force introduction surface 200 is intended to mean a shortest distance from an edge of the distribution opening 40, 40 to an edge of the force introduction surface 200 of less than 20 mm, preferably less than 10 mm.
[0043]
[0044] In a first step of the process for installing the sensor arrangement 1 in the carriageway, a groove 60 is formed in the carriageway.
[0045] In a second process step for installing the sensor arrangement 1 in the carriageway, the empty groove 60 is partially filled with grout 5. Grout 5 consists of mechanically resistant, curable material such as polyester resin, epoxy resin, etc. Such grout 5 is sold commercially by the applicant under the type Nos. 1000A1, 1000A3. Grout 5 is filled into the groove 60 in a viscous state and cures in less than 1 h to 2 h depending on the temperature. While it cures, grout 5 undergoes a material connection with the bottom 600 and the lateral surfaces 601, 601.
[0046] In a further process step for installing the sensor arrangement 1, the sensor arrangement 1 is introduced in the groove 60 and positioned in the groove 60.
[0047] Preferably, the force anchoring flange 22 of the sensor arrangement 1 is positioned in the not yet cured grout 5 so that the force anchoring flange 22 is completely surrounded by grout 5 in the lower space 50. Preferably, anchoring 220 is completely surrounded by grout 5. Preferably, the grout 5 extends up to the transition region between the tubular part 21 and the force anchoring flange 22. Preferably, the grout 5 surrounds a lower end 41, 41 of the separating element 4, 4, 4. While it cures, the grout 5 undergoes a material connection to the lower end 41, 41 of the separating element 4, 4, 4. Preferably, the sensor arrangement 1 is positioned in the groove 60 in such a way that an upper end 42, 42 of the separating element 4, 4, 4 is flush with the carriageway surface level E. Preferably, the sensor arrangement 1 is anchored in the groove 60 in this position by the curing of the grout 5 that surrounds the force anchoring flange 22. Once the grout 5 is finished curing, the grout 5 forms a material connection to the force anchoring flange 22.
[0048] In yet another process step for installation of the sensor arrangement 1, the groove 60 with the sensor arrangement 1 positioned therein is completely filled with grout 5.
[0049] The first embodiment of a sensor arrangement 1 according to Fig, 7 comprises two separating elements 4, 4. A first separating element 4 is arranged in front of the hollow profile 2 as seen in the direction of travel F. A second separating element 4 is arranged behind the hollow profile 2 as seen in the direction of travel F. As seen in and along the travel direction F, there is a first lateral space 52 between a first lateral surface 601 and the first separating element 4 and a second lateral space 52 is located between a second lateral surface 601 and the second separating element 4.
[0050] The second embodiment of a sensor arrangement 1 according to
[0051] Each separating element 4, 4, 4 comprises a plurality of distribution openings 40, 40. The upper space 51 communicates with the two lateral spaces 52, 52 via distribution openings 40, 40 in the separating means 4, 4, 4. In this way, the grout 5 is distributed quickly and easily in the space provided for grout 5 around the sensor arrangement 1.
[0052] The separating element 4, 4, 4 comprises upper ends 42, 42 which are flush with the carriageway surface level E after the sensor arrangement 1 has been placed in the groove 30. If wheel ruts are present in the carriageway surface level E, the upper ends 42, 42 can be mechanically deformed due to their high elasticity so that they are neither positioned below nor above the carriageway surface level E but are instead positioned accurately flush with of the carriageway surface level E. Preferably, grout 5 is distributed in the upper space 51 and in the lateral space 52, 52 in such a way that the first upper end 42 and the second upper end 42 remain parallel to each other and flush with the carriageway surface level E. Preferably, when distributing the grout 5 in the upper space 51 and in the lateral space 52, 52 the upper ends 42, 42 are held in a parallel position to each other by means of a suitable tool such as a clamp. This ensures that the ends 42, 42 extend up to the carriageway surface level E and effectively prevent the introduction of rolling forces in the hollow profile 2 especially in a region close to the carriageway surface level E where strong rolling forces act also after the grout 5 was cast.
LIST OF REFERENCE NUMERALS
[0053] E carriageway surface level
[0054] F direction of travel
[0055] L longitudinal direction
[0056] Q transverse direction
[0057] V vertical direction
[0058] 1 sensor arrangement
[0059] 2 hollow profile
[0060] 3 piezoelectric measuring arrangement
[0061] 4, 4, 4 separating element
[0062] 5 grout
[0063] 6 pavement
[0064] 7, 7 insulating foam part
[0065] 20 force introduction flange
[0066] 21 tubular part
[0067] 22 force anchoring flange
[0068] 40, 40 distribution opening
[0069] 41, 41 lower end of separating element
[0070] 42, 42 upper end of separating element
[0071] 43 spacer element
[0072] 60 groove
[0073] 200 force introduction surface
[0074] 210 attachment surface
[0075] 220 anchoring
[0076] 50 lower space
[0077] 51 upper space
[0078] 52, 52 lateral space
[0079] 600 bottom of groove
[0080] 601, 601 lateral surface of groove