CN217083645U

CN217083645U - Bridge strain testing device

Info

Publication number: CN217083645U
Application number: CN202123041596.4U
Authority: CN
Inventors: 陆忠华
Original assignee: Suzhou Traffic Engineering Testing Center Co ltd
Current assignee: Suzhou Traffic Engineering Testing Center Co ltd
Priority date: 2021-12-06
Filing date: 2021-12-06
Publication date: 2022-07-29
Anticipated expiration: 2031-12-06

Abstract

The utility model provides a bridge strain test device, includes a slice test base plate, four base pieces and four support roof beams averagely divide into two sets ofly and arrange respectively in the both sides of test base plate, two support roof beams of every group pass through middle part pivot rotatable coupling, each the lower extreme of support roof beam respectively with one the base piece is articulated, each the upper end of support roof beam is articulated with test base plate. The testing device has high testing precision, is simple to operate and can be repeatedly used.

Description

Bridge strain testing device

Technical Field

The utility model relates to a bridge load test field, concretely relates to bridge strain test device.

Background

In the static and dynamic load tests of the bridge, the bridge strain is one of the basic test parameters. At present, the basic idea of measuring bridge stress is to adhere a sensor to a bridge body column part, and the stress borne by a bridge is obtained by measuring the numerical value change of the sensor when the bridge is unloaded and loaded and by the conversion and calculation of numerical values.

Electrical resistance strain gauges, simply strain gauges (also known as electrical resistance strain gauges or simply strain gauges), are among the more common electrical measurement instruments. It consists of four parts. The first is a resistance wire (sensitive grid), which is the conversion element of the strain gauge; secondly, a substrate and surface glue (or a covering layer), wherein the substrate is an intermediate medium for transferring the strain on the surface of the bridge body cylinder to the resistance wire grid and plays an insulating role between the resistance wire and the bridge body cylinder, and the surface glue plays a role in protecting the resistance wire; thirdly, adhesive is used for sticking the resistance wire and the substrate together; and the fourth is a leading-out wire, which is used for connecting the measuring lead.

The strain gauge converts the change of strain into the relative change of resistance, and also converts the change of resistance into the change of voltage or current, so that the measurement can be carried out by an electric measuring instrument. Since the mechanical strain is generally small, and the resistance change range of the resistance strain type is also small, it is difficult to directly measure the small change, so a bridge type measuring circuit is generally used to amplify the small resistance change to realize accurate measurement.

Before the strain gauge is adhered, the bridge body column is usually required to be finely ground, but the strain gauge is easy to be punctured or adhered unevenly during the adhering process, and the phenomenon is difficult to be found, so that the deviation of the test result is large. Secondly. Although the amplification operation can be performed by the bridge, the test accuracy is difficult to guarantee because the base number of the resistance change is too small. Additionally, strain gauges are typically disposable and are not reusable.

Disclosure of Invention

For overcoming the above-mentioned technical problem that prior art exists, the utility model provides a bridge strain test device, including a slice test base plate, four base pieces and four support roof beams averagely divide into two sets ofly and arrange respectively in the both sides of test base plate, two support roof beams of every group pass through middle part pivot rotatable coupling, each the lower extreme of support roof beam respectively with one the base piece is articulated, each the upper end of support roof beam is articulated with the test base plate.

Furthermore, a resistance sensitive grid is arranged on the surface of the test substrate.

Furthermore, a resistance strain gauge is adhered to the surface of the test substrate.

Furthermore, the length of the upper end pin joint of each support beam to the middle pivot is a, and the length of the lower end pin joint of each support beam to the middle pivot is b, and the support beam is characterized in that: a is greater than or equal to b.

Furthermore, the lower surface of each base block is provided with an adhesive, or each base block is provided with a fixing hole.

The utility model discloses gained apparent beneficial effect, the resistance strain sensing element arranges in the test substrate, and it is fixed with the test surface of bridge through the base piece, need not to polish to the test surface is fine, has reduced the high accuracy requirement of paster. In addition, the whole testing device is disassembled, so that the resistance strain sensitive element on the testing substrate is not influenced, and the repeated use of the strain gauge can be realized. In addition, when a is larger than b, the mechanical amplification of strain can be realized, the amplification factor is reliable, and the detection is more facilitated.

Drawings

FIG. 1 is a perspective view of an embodiment of the present invention

Figure 2 is a front view of an embodiment of the invention

Detailed Description

Example 1

Referring to fig. 1 and 2, the utility model provides a bridge strain test device includes a slice test substrate 1, four base pieces 2 and four support beams 3, four support beams 3 averagely divide into two sets ofly and arrange respectively in test substrate 1's both sides, two support beams 3 of every group pass through middle part pivot rotatable coupling, each support beam 3's lower extreme respectively with one base piece 2 is articulated, each support beam 3's upper end and test substrate 1's articulated. The surface of the test substrate 1 is provided with a resistance sensitive grid, or the surface of the test substrate is adhered with an existing resistance strain gauge in specific use. The length from the upper end hinge point of each support beam 3 to the middle pivot is a, the length from the lower end hinge point of each support beam 3 to the middle pivot is b, and a is greater than or equal to b, so that strain can be amplified in equal proportion as required. The lower surface of each base block 2 is provided with an adhesive (not shown in the figure) which is directly adhered to a test surface when in use, or each base block 2 is provided with a fixing hole (not shown in the figure) which is fixed on the test surface through a structure such as a bolt.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a bridge strain test device which characterized in that: the device comprises a test substrate (1), four base blocks (2) and four support beams (3), wherein the four support beams (3) are averagely divided into two groups and are respectively arranged on two sides of the test substrate (1), the two support beams (3) of each group are rotatably connected through a middle pivot, the lower end of each support beam (3) is respectively hinged with one base block (2), and the upper end of each support beam (3) is hinged with the test substrate (1).

2. The bridge strain test device of claim 1, wherein: and the surface of the test substrate (1) is provided with a resistance sensitive grid.

3. The bridge strain test device of claim 1, wherein: and a resistance strain gauge is adhered to the surface of the test substrate (1).

4. The bridge strain test device of claim 1, wherein: the length from the upper end hinge point of each support beam (3) to the middle pivot is a, the length from the lower end hinge point of each support beam (3) to the middle pivot is b, and a is larger than or equal to b.

5. The bridge strain test apparatus of any one of claims 1 to 4, wherein: the lower surface of each base block (2) is provided with an adhesive, or each base block (2) is provided with a fixing hole.