SYSTEM FOR DETECTING PROPERTIES OF A MATERIAL LAYER

Abstract

A system detects properties of a material layer or an embedded component of a structure or its sub-structure. The system includes a detection layer which has reflective regions reflecting electromagnetic radiation and which is designed to be embedded into a structure or its sub-structure, and a detection device which is designed to output electromagnetic radiation in the direction of the detection layer and to receive electromagnetic radiation reflected by the reflective regions of the detection layer, wherein fibers reflecting electromagnetic radiation are arranged in the reflection regions of the detection layer.

Claims

1. A system for detecting properties of a material layer or of an embedded component part of a structure or its substructure, the system comprising: a detection layer, which is provided with reflective regions that reflect electromagnetic radiation and is set up to be embedded in a structure or its substructure; and with a detection device, which is set up to emit electromagnetic radiation in the direction of the detection layer and to receive electromagnetic radiation reflected from the reflective regions of the detection layer; wherein a plurality of fibers that reflect electromagnetic radiation are disposed in the reflective regions of the detection layer.

2. The system according to claim 1, wherein the plurality of fibers are disposed in fiber bundles, the fiber bundles reflect electromagnetic radiation and the fiber bundles are disposed in the reflective regions or the fibers that reflect electromagnetic radiation form several detection strips that are spaced apart from one another and reflect electromagnetic radiation (24).

3. The system according to claim 1, wherein the detection layer is formed as a geotextile or comprises a geotextile, and wherein the fibers that reflect electromagnetic radiation are fixed on the geotextile or are integrated into the geotextile.

4. The system according to claim 3, wherein the geotextile is formed as a woven, knitted or nonwoven fabric.

5. The system according to claim 3, characterized in that the fibers that reflect electromagnetic radiation are fixed on a surface of the geotextile.

6. The system according to claim 3, wherein the fibers that reflect electromagnetic radiation are incorporated into the geotextile by weaving, machine knitting, raschel knitting, sewing or embroidering.

7. The system according to claim 1, wherein the detection layer is formed from a fiber composite material or comprises a fiber-composite material, and wherein the fibers that reflect electromagnetic radiation are fixed on the fiber-composite material or are integrated into the fiber-composite material.

8. The system according to claim 1, wherein the radiation-reflecting fibers are formed as carbon fibers.

9. The system according to claim 1, wherein the detection layer is formed as a reinforcing grid or is integrated into a reinforcing grid.

10. The system according to claim 1, wherein the detection device comprises an evaluation unit, which is set up to determine the course (V), the thickness or an imposed elongation of a material layer or of a component part of the structure or of its substructure by evaluation of the emitted and received electromagnetic radiation.

11. A substructure for a roadway, the substructure comprising: a detection layer, which is disposed between two material layers of the substructure and is provided with reflective regions that reflect electromagnetic radiation; wherein fibers that reflect electromagnetic radiation are disposed in the reflective regions of the detection layer.

12. A method of detecting properties of a material layer or of an embedded component part of a structure or its substructure, using a system for detecting properties of a material layer or of an embedded component part of a structure or its substructure, the system comprising: a detection layer, which is provided with reflective regions that reflect electromagnetic radiation and is set up to be embedded in a structure or its substructure; and with a detection device, which is set up to emit electromagnetic radiation in the direction of the detection layer and to receive electromagnetic radiation reflected from the reflective regions of the detection layer; wherein a plurality of fibers that reflect electromagnetic radiation are disposed in the reflective regions of the detection layer; the method comprising the steps of: emitting, using a detection device of the system, electromagnetic radiation in the direction of a detection layer, which is embedded in a structure or its substructure, and receiving, using the detection device, the electromagnetic radiation reflected from the detection layer; wherein the electromagnetic radiation emitted by the detection device is reflected by fibers that reflect electromagnetic radiation and are disposed in reflective regions of the detection layer.

13. The method according to claim 12, further comprising determining, by an evaluation unit of the detection device, the course (V) or the position (Pa, Pb) of a material layer or of an embedded component part of the structure or its substructure by means of evaluation of the emitted and received electromagnetic radiation; determining, by an evaluation unit of the detection device, the thickness of a material layer or of an embedded component part of the structure or its substructure by means of evaluation of the emitted and received electromagnetic radiation; determining, by an evaluation unit of the detection device, the elongation of a material layer or of an embedded component part of the structure or its substructure by means of evaluation of the emitted and received electromagnetic radiation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Preferred embodiments of the invention will be explained and described in more detail hereinafter with reference to the attached drawings, wherein:

[0040] FIG. 1 shows an exemplary embodiment of the inventive system in a perspective diagram;

[0041] FIG. 2 shows the determination of the course of a layer by means of the inventive method in a schematic diagram;

[0042] FIG. 3 shows the determination of a component-part position by means of the inventive method in a schematic diagram;

[0043] FIG. 4 shows the determination of a component-part position by means of the inventive method in a schematic diagram;

[0044] FIG. 5 shows a detection layer of an inventive system in a schematic diagram;

[0045] FIG. 6 shows a further detection layer of an inventive system in a schematic diagram;

[0046] FIG. 7 shows a further detection layer of an inventive system in a schematic diagram;

[0047] FIG. 8 shows a further detection layer of an inventive system in a schematic diagram;

[0048] FIG. 9 shows a further detection layer of an inventive system in a schematic diagram;

[0049] FIG. 10 shows a further detection layer of an inventive system in a schematic diagram; and

[0050] FIG. 11 shows a further detection layer of an inventive system in a schematic diagram.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0051] FIG. 1 shows a structure 100 constructed as a railroad track, which has crossties 102a-102f spaced apart in longitudinal direction L. Crossties 102a-102f extend in transverse direction Q, i.e. across longitudinal direction L. Two parallel rails 104a, 104b extend on crossties 102a-102f.

[0052] A substructure 200 having at least one material layer 202 is situated underneath track 100. A detection layer 16 introduced during construction of substructure 200 is situated underneath material layer 202. The layer thickness of material layer 202 can be determined nondestructively and contactlessly via detection layer 16 introduced into substructure 200.

[0053] For this purpose, a system 10 is used that comprises not only detection layer 16 but also an inspection vehicle 12. Inspection vehicle 12 is a rail-mounted vehicle, which moves along rails 104a, 104b in travel direction F. Inspection vehicle 12 may have its own drive or be moved by a third vehicle.

[0054] Detection device 14 is set up to emit electromagnetic radiation 24 in the direction of detection layer 16 and to receive electromagnetic radiation 26 reflected from detection layer 16. For radiation reflection, detection layer 16 comprises several reflective regions 20a-20e, wherein reflective regions 20a-20e comprise fibers 22 that reflect electromagnetic radiation 24. In the present case, fibers 22 are carbon fibers or carbon fibers.

[0055] Fiber bundles containing a multiplicity of radiation-reflecting fibers 22 are respectively disposed in reflective regions 20a-20e, wherein the fibers 22 form detection strips that are spaced apart from one another and that reflect electromagnetic radiation 24. Detection layer 16 comprises a geotextile 18, wherein radiation-reflecting fibers 22 are integrated into geotextile 18.

[0056] FIG. 2 shows the determination of a course V of a boundary layer between two material layers 202a, 202b. For this purpose, a detection layer 16 was introduced between the two material layers 202a, 202b during construction of substructure 200. The course V of the boundary layer between the two material layers 202a, 202b may be determined via the course of detection layer 16.

[0057] Detection layer 16 contains reflective regions 20a-20e that reflect electromagnetic radiation 24. A detection device 14 is moved above substructure 200 along the main extension direction of detection layer 16 in a manner spaced apart from detection layer 16. During this movement, detection device 14 emits electromagnetic radiation 24 comprising radar waves in the direction of detection layer 16. At least part of the emitted electromagnetic radiation 24 is reflected by reflective regions 20a-20e of detection layer 16, so that detection device 14 is able to receive the reflected electromagnetic radiation 26 once again.

[0058] On the basis of the known velocity of propagation of the emitted electromagnetic radiation 24, it is possible to perform transit-time measurements L1-L5, in order to be able to determine the distance between detection layer 16 and detection device 14 at several measurement points P1-P5. The course V of detection layer 16 and thus the course of the boundary layer between material layers 202a, 202b may be determined via measurement points P1-P5. The precision of this determination of the course may be improved via the number of points of measurement.

[0059] FIG. 3 schematically shows the detection of a component-part position Pa of a component part 204a. Component part 204a is a pipe segment that is part of a substructure 200. Component part 204a is embedded in a material layer. A detection layer 16, which comprises fibers 22 that reflect electromagnetic radiation 24, is situated on the upper side of component part 204a.

[0060] For position determination, a detection device 14 is moved transversely relative to the longitudinal axis of component part 204a. During this movement, detection device 14 emits electromagnetic waves 24 and receives electromagnetic radiation 26 reflected from detection layer 16.

[0061] Via several transit-time measurements L1-L5, which are made by an evaluation unit, it is possible to identify measurement points P1-P5 via a distance determination that takes into consideration the velocity of propagation of the electromagnetic radiation 24, 26. Component-part position Pa may then be determined via measurement points P1-P5.

[0062] Detection device 14 may be set up to emit electromagnetic radiation 24 obliquely forward, vertically downward and obliquely backward and to receive from these directions. As FIG. 3 shows, this is advantageous in particular in the case of curved component-part geometries.

[0063] FIG. 4 shows position detection for a component part 204b, wherein component part 204b is an embedded base plate. Component part 204b is therefore likewise part of a substructure 200.

[0064] A detection layer 16, which comprises fibers 22 that reflect electromagnetic radiation 24, is again situated on the upper side of component part 204b. Due to the emission of electromagnetic radiation 24 by means of a detection device 14 in the direction of detection layer 16 and subsequent reception of the reflected electromagnetic radiation 26, it is possible to determine the distance of component part 204b from the path of movement of detection device 14 at several measurement points P1-P5 via a transit-time evaluation. Component-part position Pb may again be determined via measurement points P1-P5.

[0065] FIG. 5 shows a detection layer 16 containing several reflective regions 20a-20e. Reflective regions 20a-20e are formed by fiber bundles of carbon fibers 22.

[0066] Detection layer 16 comprises a geotextile 18 formed as a nonwoven fabric, wherein the fiber bundles of carbon fibers 22 are fixed on the geotextile 18. For example, the fibers 22 may be vapor-deposited, glued or raschel-knitted onto the surface of geotextile 18.

[0067] FIG. 6 shows a detection layer in which its geotextile 18 is formed as a woven fabric. Carbon fibers 22 are incorporated into the woven fabric. As examples, carbon fibers 22 may be woven, sewn or embroidered into geotextile 18.

[0068] FIGS. 7 and 8 show that the detection strips of carbon fibers 22 may be joined with one another in electrically conductive manner via connecting threads 28a-28c. The reflective properties of detection layer 16 are improved via the electrically conductive connection. The diagrams show examples of a joint region 30, in which connecting threads 28a are connected electrically conductively with reflective region 20a. By means of a textile-manufacturing process, connecting threads 28a-28c may be applied on geotextile 18 or incorporated into geotextile 18.

[0069] FIGS. 9 and 10 show detection layers 16, in which carbon fibers 22 of a fiber bundle are joined with one another at their respective ends in electrically conducting manner by means of a connecting element 32a, 32b. In the present case, connecting elements 32a, 32b are terminals made from an electrically conductive material. Alternatively to the illustrated terminals, other connection elements 32a, 32b may also be used, via which an electrically conductive substance-to-substance bond, frictional connection and/or interlocking connection is implemented between the carbon fibers 22 of a fiber bundle.

[0070] FIG. 11 shows a detection layer 16, in which a thread 34 comprising a carbon fiber 22 is incorporated as a weft thread into a geotextile 18 formed as a woven fabric. Thread 34 may either be a pure carbon thread or in addition to carbon fibers 22 may comprise still further different fibers. Thread 34 comprises several straight thread segments 36a-36e and several curved thread segments, via which the straight thread segments 36a-36e are joined to one another. Straight thread segments 36a-36e are spaced equidistantly from one another and extend parallel to one another.

[0071] Alternatively, a thread 34 comprising a carbon fiber 22 could also be incorporated as a weft thread into a geotextile 18, formed as a woven fabric, of detection layer 16.

[0072] Alternatively or in addition to the illustrated carbon threads 22, reflective regions 20a-20e of a detection layer 16 may also comprise metal threads. Detection layer 16 may be formed as a reinforcing grid or be integrated into a reinforcing grid.

REFERENCE SYMBOLS

[0073] 10 System [0074] 12 Inspection vehicle [0075] 14 Detection device [0076] 16 Detection layer [0077] 18 Geotextile [0078] 20a-20e Reflective regions [0079] 22 Fibers [0080] 24 Radiation [0081] 26 Radiation [0082] 28a-28c Connecting threads [0083] 30 Joint region [0084] 32a, 32b Connecting elements [0085] 34 Thread [0086] 36a-36e Thread segments [0087] 100 Structure [0088] 102a-102f Crossties [0089] 104a, 104b Rails [0090] 200 Substructure [0091] 202, 202a, 202b Material layers [0092] 204a, 204b Component part [0093] F Travel direction [0094] L Longitudinal direction [0095] L1-L5 Transit-time measurements [0096] Q Transverse direction [0097] P1-P5 Measurement points [0098] Pa, Pb Component-part positions [0099] V Course