Concealed fatigue crack propagation detection device, device and system

Abstract

The utility model discloses a concealed fatigue crack propagation detection device, device and system, which belong to the technical field of bridge detection, and comprise two layers of insulating gauzes, a crack detection circuit, a series external power supply fixedly arranged between the two layers of insulating gauzes and detachably arranged between the two ends of the circuit, and a resistance change monitoring mechanism, the crack detection circuit is provided with a plurality of parallel resistors which are connected in series and two first resistors are connected in parallel by conductive yarns; according to the utility model, the development condition of cracks can be monitored in real time by detecting the change condition of the resistance value of the circuit through the resistance change monitoring mechanism.

Description

Technical Field

[0001] The utility model belongs to the technical field of bridge detection, and in particular relates to a concealed fatigue crack extension detection device, an apparatus and a system thereof. Background Art

[0002] In the field of bridge construction inspection, the fatigue crack problem of steel bridge decks has always been the focus of attention in the engineering community. As an important part of the bridge structure, the steel bridge deck has long been under the dual influence of traffic loads and environmental factors, which can easily lead to fatigue cracks. At present, the commonly used maintenance and reinforcement method is to use steel plates to reinforce, that is, to weld steel plates to the crack area to enhance its bearing capacity. However, this method has obvious shortcomings: after the steel plate is reinforced, the crack tip is completely covered, making subsequent tracking inspections difficult, and it is impossible to understand the development of the crack in time, thereby failing to effectively prevent potential safety risks.

[0003] In addition, due to the lack of effective means to detect the growth of hidden cracks, once the cracks grow to a certain extent, they may suddenly break, causing serious safety accidents. Therefore, developing a device that can detect the growth of hidden fatigue cracks after repair and reinforcement is of great significance to ensuring the safety of bridge structures and extending their service life. Utility Model Content

[0004] The utility model aims to overcome the deficiencies in the prior art and provide a concealed fatigue crack extension detection device, apparatus and system thereof.

[0005] In order to achieve the above purpose, the utility model is implemented by adopting the following technical solutions:

[0006] In a first aspect, the utility model provides a concealed fatigue crack extension detection device, comprising:

[0007] Two layers of insulating gauze,

[0008] A crack detection circuit is fixedly arranged between two layers of insulating gauze and has a detachable series external power supply and a resistance change monitoring mechanism between both ends of the circuit, wherein the crack detection circuit is configured with a plurality of parallel resistors in series with two first resistors connected in parallel by conductive yarn.

[0009] Furthermore, the plurality of parallel resistors and the conductive yarns are arranged in parallel in sequence.

[0010] Furthermore, at least one second resistor for protecting the circuit is connected in series between the two ends of the crack detection circuit.

[0011] Furthermore, the resistance change detection mechanism includes a signal transmitting device with a built-in encoder and a monitoring terminal communicatively connected to the signal transmitting device.

[0012] In a second aspect, the utility model provides a hidden fatigue crack extension detection device, comprising:

[0013] power supply,

[0014] Resistance change monitoring mechanism,

[0015] And the hidden fatigue crack extension detection device as described in any one of the first aspects, wherein an external power supply and a resistance change monitoring mechanism are connected in series between the two ends of the crack detection circuit.

[0016] In a third aspect, the utility model provides a hidden fatigue crack growth detection system, which is configured to detect fatigue cracks in steel bridge decks, comprising:

[0017] Steel bridge deck with fatigue cracks,

[0018] Repair and reinforce the steel plate to cover the fatigue crack.

[0019] A concealed fatigue crack extension detection device, power supply and resistance change monitoring mechanism as described in any one of the first aspects of the right; wherein, the two layers of the insulating gauze are fixedly arranged between the steel bridge deck and the repair and reinforcement steel plate, and the crack detection circuit is located on the extension line of the fatigue crack, and the extension line direction is perpendicular to the conductive yarn between the two first resistors in the parallel resistor.

[0020] Compared with the prior art, the beneficial effects achieved by the utility model are as follows: the hidden fatigue crack extension detection device, apparatus and system provided by the utility model adopt an extension detection device set between the steel bridge deck and the repair and reinforcement steel plate, and a resistance change monitoring mechanism is used to detect the change of circuit resistance value to monitor the development of cracks in real time. It can also provide a scientific basis for the maintenance and management of bridges to a certain extent, reduce maintenance costs and improve the operating efficiency of bridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of a hidden fatigue crack extension detection device provided according to an embodiment of the utility model;

[0022] Figure 2 This is a detection schematic diagram of a hidden fatigue crack extension detection device provided according to an embodiment of the utility model

[0023] In the figure:

[0024] 1. Insulating gauze; 2. First resistor; 3. Conductive yarn; 4. Wire; 5. Second resistor; 6. Power supply; 7. Signal transmitter; 8. Fatigue crack. DETAILED DESCRIPTION

[0025] The utility model is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

[0026] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0028] like Figure 1 and Figure 2 As shown, in an embodiment of the utility model, a hidden fatigue crack extension detection device is provided, comprising:

[0029] Two layers of insulating gauze 1, used for insulating and wrapping the crack detection circuit for protection;

[0030] The crack detection circuit is fixedly arranged between two layers of insulating gauze 1 and has a detachable series external power supply 6 and a resistance change monitoring mechanism between both ends of the circuit, wherein the crack detection circuit is configured with a plurality of parallel resistors in series, which are two first resistors 2 connected in parallel by conductive yarn 3.

[0031] In this embodiment, the plurality of parallel resistors and the conductive yarn 3 are arranged in parallel in sequence, wherein the conductive yarn material characteristics are conductive, thin and easy to break.

[0032] At least one second resistor 5 for protecting the circuit is also connected in series between the two ends of the crack detection circuit.

[0033] The resistance change detection mechanism includes a signal transmitting device 7 with a built-in encoder and a monitoring terminal connected to the signal transmitting device 7 for communication, which is used to convert the line resistance value into a crack length value, and then the signal transmitting device 7 sends the crack length value to the monitoring terminal for real-time monitoring.

[0034] It should be noted that in the embodiments of the utility model, no specific limitations or improvements are made to the signal transmitting device 7, the monitoring terminal, and the signal transmission method of the built-in encoder. Conventional signal transmission methods of the existing technology can be used, including wireless transmission and wired transmission of signals, etc. The technical solution only improves the circuit structure of the components and devices themselves.

[0035] like Figure 1 As shown, the embodiment of the utility model provides a hidden fatigue crack extension detection device, comprising:

[0036] Power Supply 6,

[0037] Resistance change monitoring mechanism,

[0038] And the above-mentioned hidden fatigue crack 8 extension detection device, wherein an external power supply 6 and a resistance change monitoring mechanism are connected in series between the two ends of the crack detection circuit.

[0039] In addition, the embodiment of the utility model further provides a hidden fatigue crack growth detection system, which is configured to detect fatigue cracks 8 of steel bridge decks, and includes:

[0040] Steel bridge deck with fatigue crack 8,

[0041] Repair and reinforce the steel plate to cover the fatigue crack 8.

[0042] and the aforementioned hidden fatigue crack 8 extension detection device, power supply 6 and resistance change monitoring mechanism;

[0043] Among them, the two layers of insulating gauze 1 are fixedly arranged between the steel bridge deck and the repair and reinforcement steel plate, the crack detection circuit is located on the extension line of the fatigue crack 8, and the extension line direction is perpendicular to the conductive yarn 3 between the two first resistors 2 in the parallel resistor.

[0044] In this embodiment, the insulating gauze 1, the conductive yarn 3, etc. can be firmly fixed and arranged by 502 glue, so that when the fatigue crack 8 of the steel bridge deck further breaks to the detection circuit, the insulating gauze 1 and the conductive yarn 3 will break, thereby affecting the change of resistance value in the circuit.

[0045] In this embodiment, the specific operation and use method of the hidden fatigue crack 8 extension detection system is briefly described as follows:

[0046] Step 1) Grind and remove rust from the steel bridge deck to make the surface of the steel bridge deck smooth and clean, and fix the lower insulating gauze 1 with glue so that it is located on the extension development path or direction of the fatigue crack 8 to be tested.

[0047] Step 2) The hidden fatigue crack 8 extension detection device is glued to the lower insulating gauze 1 by glue, and is located in the extension development path or direction of the fatigue crack 8 to be detected, such as Figure 2 As shown, each conductive yarn 3 arranged in parallel must be perpendicular to the direction of the extension path of the fatigue crack 8.

[0048] Step 3) Use 502 glue to fix the conductive yarn 3, the upper insulating gauze 1 and the repair and reinforcement steel plate so that the whole fits firmly without shaking.

[0049] Step 4) Connect and debug the power supply 6, the second resistor 5, the signal transmitter 7 of the built-in encoder, the monitoring terminal and other equipment.

[0050] Step 5) Figure 2 As shown, when the fatigue crack 8 further breaks and expands, reaching the detection circuit and causing the conductive yarn 3 to break, the resistance value of the parallel resistor in the circuit changes, thereby causing the signal transmitting device 7 of the built-in encoder to respond and convert it into a crack length value based on the line resistance value. Then the signal transmitting device 7 sends the crack length value to the monitoring terminal for real-time monitoring.

[0051] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A hidden fatigue crack growth detection device, characterized in that: include: Two layers of insulating gauze, The crack detection circuit is fixedly arranged between two layers of insulating gauze and has a detachable series external power supply and a resistance change monitoring mechanism between the two ends of the circuit. The crack detection circuit is configured with a plurality of parallel resistors in series, which are two first resistors connected in parallel by conductive yarn.

2. The hidden fatigue crack extension detection device according to claim 1, characterized in that: The plurality of parallel resistors and the conductive yarns are arranged in parallel in sequence.

3. The hidden fatigue crack extension detection device according to claim 2, characterized in that: At least one second resistor for protecting the circuit is also connected in series between the two ends of the crack detection circuit.

4. The hidden fatigue crack extension detection device according to claim 3, characterized in that: The resistance change monitoring mechanism comprises a signal transmitting device with a built-in encoder and a monitoring terminal connected to the signal transmitting device for communication.

5. A hidden fatigue crack growth detection device, characterized in that: include: power supply, Resistance change monitoring mechanism, And the hidden fatigue crack extension detection device according to any one of claims 1 to 4, wherein an external power supply and a resistance change monitoring mechanism are connected in series between the two ends of the crack detection circuit.

6. A hidden fatigue crack growth detection system, configured to detect fatigue cracks in steel bridge decks, characterized in that: include: Steel bridge deck with fatigue cracks, Repair and reinforce the steel plate to cover the fatigue crack. The hidden fatigue crack extension detection device, power supply and resistance change monitoring mechanism as claimed in any one of claims 1 to 4; in, The two layers of insulating gauze are fixedly arranged between the steel bridge deck and the repair and reinforcement steel plate. The crack detection circuit is located on the extension line of the fatigue crack, and the extension line direction is perpendicular to the conductive yarn between the two first resistors in the parallel resistor.

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