Fiber bragg grating force measuring support

Abstract

The utility model discloses a fiber bragg grating force measuring support, and relates to the technical field of bridge supports. The device comprises an upper seat plate, a middle steel lining plate and a bottom basin, a plane sliding plate is arranged on the top face of the middle steel lining plate, and the upper seat plate is arranged at the top end of the middle steel lining plate in a sleeved mode. According to the utility model, a force measuring function is added on the basis of the existing support, so that the support is suitable for medium and small span beam bridges with the market proportion of more than 80%, traditional basin-type supports and spherical supports with larger market shares can be upgraded, and the popularization prospect is wide; the arrangement of the fiber bragg grating force measurement assembly fully utilizes the original structure of a traditional support, the influence on the size and height of the support is small, and the force measurement method is simple and reliable; the fiber bragg grating force measurement assembly is a force measurement sensing system constructed based on the axial strain characteristic of a fiber bragg grating (FBG), has the characteristics of high electromagnetic interference resistance, good electrical insulating property, corrosion resistance, high precision, low operation and maintenance cost and the like, is easy to realize distributed detection, and is suitable for working in a complex and severe environment.

Description

Technical Field

[0001] This utility model relates to the field of bridge bearing technology, specifically to a fiber optic grating force measuring bearing. Background Technology

[0002] Bridge bearings occupy a crucial position at the connection between the superstructure and substructure of a bridge. Their primary function is to transfer the load from the superstructure to the substructure, ensuring that the actual stress condition of the structure meets design requirements and protecting beam ends and pier caps from damage. If a bridge experiences excessive pressure on some or all bearings due to factors such as vehicle overloading, uneven settlement, or sudden disasters, exceeding its bearing capacity limit, the abnormal bearing capacity cannot be detected in time. This reduces the safety and reliability of the bridge, potentially leading to bridge collapse and posing a serious threat to people's lives and property. Currently, small- and medium-span beam bridges (span ≤ 40m) account for over 80% of the total number of highway and urban road bridges in my country. These bridges often use plate bearings, conventional pot bearings, and spherical bearings. However, conventional pot bearings and spherical bearings cannot be monitored during bridge operation, making it impossible to obtain vertical bearing capacity data and assess the operational health of the bridge structure based on bearing stress data.

[0003] Therefore, it is necessary to develop a new type of force-measuring bearing, adding force-measuring functionality to conventional pot bearings and spherical bearings. This upgrades traditional pot bearings and spherical bearings, which occupy a large market share, and safeguards the operational safety of existing and newly built bridges. Currently, most force-measuring bearings combine pot bearings with pressure sensors. The pressure sensor passes through the pot ring and contacts the pressure-bearing rubber pad inside the pot cavity. By detecting the horizontal pressure of the pressure-bearing rubber pad on the pressure sensor, the vertical bearing capacity of the bearing is determined. Equating the vertical bearing capacity of the pressure-bearing rubber pad with the horizontal pressure is based on Pascal's principle. Pascal's principle is a law of fluid statics, stating that in an incompressible, stationary fluid, any pressure applied at any point is transmitted equally in all directions of the fluid. Pascal's law only applies to liquids. Due to the fluidity of liquids, pressure changes occurring in a portion of a stationary fluid in a closed container will be transmitted in all directions without change in magnitude. Pressure equals the applied force divided by the area of ​​the force application. Although pressure-bearing rubber pads exhibit a certain degree of fluidity under pressure, this fluidity is based on the characteristics of non-Newtonian fluids. Non-Newtonian fluids do not obey "Newton's laws of flow," and there is internal friction between their layers, which creates resistance to material flow. Therefore, it is inappropriate to use the horizontal pressure of pressure-bearing rubber pads to replace the vertical bearing capacity.

[0004] Compared to fiber optic force measurement components, traditional pressure sensors are electronic components that convert pressure signals into electrical signals according to certain rules. Their service life is easily affected by external environmental factors such as temperature, humidity, vibration, noise, and electromagnetic fields. As a key component of force measurement supports, their durability and accuracy limit the service life and application of force measurement supports.

[0005] Therefore, a fiber optic grating force measuring support is proposed. Utility Model Content

[0006] The purpose of this utility model is to provide a fiber optic grating force measuring support in order to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model specifically adopts the following technical solution:

[0008] A fiber optic grating force measuring support includes a basin-type rubber support. The basin-type rubber support includes an upper base plate, an intermediate steel liner plate, and a bottom basin. A flat sliding plate is provided on the top surface of the intermediate steel liner plate, and the upper base plate is fitted onto the top of the intermediate steel liner plate. The top surface of the intermediate steel liner plate and the bottom surface of the upper base plate are fitted together. A pressure-bearing rubber pad and an intermediate steel liner plate are provided inside the bottom basin. A fiber optic grating force measuring system is provided on the surface of the intermediate steel liner plate. The fiber optic grating force measuring system includes a fiber optic grating force measuring component and a protective cover.

[0009] Furthermore, the bottom surface of the upper seat plate is made of stainless steel, chrome-plated, or polished.

[0010] Furthermore, the surface of the intermediate steel liner is provided with a groove, and the fiber optic grating force measurement system is encapsulated inside the groove.

[0011] Furthermore, both the fiber Bragg grating force measuring component and the protective cover are located inside the groove, and the protective cover is located outside the fiber Bragg grating force measuring component.

[0012] Furthermore, the fiber Bragg grating force measurement component and the protective cover are both continuously located on the periphery inside the groove, forming a continuous fiber Bragg grating force measurement system.

[0013] Furthermore, the protective cover is fastened to the intermediate steel liner by bolts or by welding.

[0014] Furthermore, the diameter of the inner wall of the groove on the surface of the intermediate steel liner is less than or equal to the diameter of the planar sliding plate.

[0015] Furthermore, the fiber optic force measurement system can also be applied to a spherical support. A groove is provided on the peripheral surface of the lower plate of the spherical support, and the fiber optic force measurement component and protective cover can be continuously arranged in the groove of the lower plate of the spherical support.

[0016] The beneficial effects of this utility model are as follows:

[0017] The fiber optic grating force measurement assembly makes full use of the existing structure of the traditional support, with minimal impact on the size and height of the support, and the force measurement method is simple and reliable. The fiber optic sensors are continuously set on the periphery of the intermediate steel backing plate, allowing the sensors to more directly monitor load changes transmitted from the upper structure, thus improving the measurement response speed and accuracy. Due to the relatively high position of the sensors, interference from external environmental factors, such as humidity, on the measurement results can be reduced, thereby increasing the stability and reliability of the data. At the same time, the central position of the support provides better protection and easier maintenance conditions, making it easier to inspect and replace the sensors when they are potentially damaged, and simplifying the wiring and installation of the sensors.

[0018] The fiber Bragg grating force measurement component is a force sensing system built based on the axial strain characteristics of fiber Bragg gratings (FBGs). It features strong resistance to electromagnetic interference, good electrical insulation, corrosion resistance, high accuracy, and low operation and maintenance costs. It is easy to implement distributed detection and is suitable for working in complex and harsh environments. By continuously positioning the fiber Bragg grating force measurement components around the periphery of the groove, a continuous fiber Bragg grating force measurement system is formed. This system can comprehensively capture the strain and stress of the intermediate steel liner in all directions, providing more balanced and accurate measurement data. The uniform arrangement design not only improves the sensor's response speed and accuracy to changes in force but also effectively avoids measurement errors caused by local stress concentration. At the same time, because the sensors are distributed around the periphery of the intermediate steel liner, they can better isolate the interference of external environmental factors on the measurement results, maintaining the stability and reliability of the data.

[0019] The fiber optic grating force measurement component can be manually monitored offline or dynamically in real time, and the monitoring data can be queried on PC and mobile devices using cloud technology.

[0020] By transmitting force downwards through the upper seat plate, flat sliding plate, intermediate steel lining plate, pressure-bearing rubber pad, and base plate, its design has a large vertical bearing capacity range and can adapt to conventional supports of various specifications. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of a movable basin-type fiber optic force-measuring rubber bearing.

[0022] Figure 2 This is a cross-sectional view of the movable basin-type fiber optic force measuring rubber support (AA).

[0023] Figure 3 This is an enlarged view of part B of the movable basin-type fiber optic force measuring rubber support;

[0024] Figure 4 This is a cross-sectional view of a fixed basin-type fiber optic force measuring rubber bearing.

[0025] Figure 5 This is a cross-sectional view of a spherical fiber optic force measuring support.

[0026] Figure 6 This is a cross-sectional view of the spherical fiber optic force measuring support AA.

[0027] Reference numerals: 1 Upper seat plate, 2 Flat sliding plate, 3 Middle steel lining plate, 4 Base plate, 5 Fiber optic grating force measurement system, 6 Pressure-bearing rubber pad, 51 Fiber optic grating force measurement assembly, 52 Protective cover, 61 Groove. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] like Figures 1 to 3 As shown, a fiber optic grating force measuring support includes an upper plate 1, an intermediate steel liner 3, and a base basin 4. A planar sliding plate 2 is provided on the top surface of the intermediate steel liner 3, and the upper plate 1 is fitted onto the top of the intermediate steel liner 3. The top surface of the intermediate steel liner 3 is in close contact with the bottom surface of the upper plate 1. A pressure-bearing rubber pad 6 and the intermediate steel liner 3 are provided inside the base basin 4. A fiber optic grating force measuring system 5 is provided on the surface of the intermediate steel liner 3. The fiber optic grating force measuring system 5 includes a fiber optic grating force measuring component 51 and a protective cover 52. ΦM is the diameter of the planar sliding plate 2, and ΦN represents the inner wall diameter of the groove (61).

[0031] The bottom surface of the upper seat plate 1 is made of stainless steel, chrome-plated, or polished.

[0032] The surface of the intermediate steel liner plate 3 is provided with a groove 61, and the fiber optic grating force measurement system 5 is encapsulated inside the groove 61.

[0033] Both the fiber Bragg grating force measuring component 51 and the protective cover 52 are located inside the groove 61, and the protective cover 52 is located outside the fiber Bragg grating force measuring component 51.

[0034] The protective cover 52 is fastened to the intermediate steel liner 3 by bolts or by welding.

[0035] The inner diameter of the groove 61 on the surface of the intermediate steel liner 3 is less than or equal to the diameter of the flat slide plate 2.

[0036] like Figure 4 As shown, in another embodiment of this utility model, when the basin support is fixed, the fiber optic grating force measurement system is set on the outer periphery of the lower cylindrical structure of the upper support plate.

[0037] like Figure 5 and Figure 6 As shown, as another embodiment of this utility model, the fiber optic grating force measurement system can also be applied to a spherical support. A groove is provided on the peripheral surface of the lower plate of the spherical support, and the fiber optic grating force measurement component and protective cover can be continuously arranged in the groove of the lower plate of the spherical support.

[0038] Working principle: The load of the upper structure of the beam is transmitted downward to the support. The magnitude of the force per unit area on the force transmission path of each component of the support is called stress, represented by the symbol σ, and the unit is Pascal (Pa).

[0039] The formula for stress is:

[0040] σ=F / A

[0041] Where F is the force acting on the object, and A is the area of ​​the object on which the force is applied.

[0042] The degree of deformation under stress is called strain, denoted by the symbol ε, and its formula is:

[0043] ε=ΔL / L

[0044] Where ΔL is the change in length of the object after being subjected to force, and L is the original length of the object.

[0045] During the elastic deformation stage of a material, its stress and strain are directly proportional (i.e., they obey Hooke's Law), and this proportionality constant is called the elastic modulus. It is usually represented by the symbol E, and its unit is Pascal (Pa). The formula is:

[0046] E=σ / ε

[0047] According to the above formula, we can obtain:

[0048] F = (E × A / L) × ΔL;

[0049] Therefore, the vertical bearing capacity F of the support is linearly related to the axial deformation ΔL of each component of the support along the force transmission path.

[0050] The fiber optic grating force measuring component 51 utilizes the axial deformation of the lower plate of the spherical support or the middle steel liner of the pot support to shift the wavelength of the fiber optic grating. By measuring the wavelength shift, the real-time vertical bearing capacity of the support can be obtained.

[0051] In summary, this utility model adds a force measurement function to the existing bearing, making it suitable for small and medium span beam bridges, which account for more than 80% of the market. The fiber optic grating force measurement component 51 makes full use of the original structure of the traditional bearing, with minimal impact on the size and height of the bearing. The force measurement method is simple and reliable. The fiber optic grating force measurement component 51 is based on the axial strain characteristics of fiber Bragg gratings (FBG) to build a force sensing system, which has the characteristics of strong anti-electromagnetic interference, good electrical insulation, corrosion resistance, high accuracy and low operation and maintenance costs. It is easy to realize distributed detection and is suitable for working in complex and harsh environments. The fiber optic grating force measurement component 51 can be monitored offline manually or in real time. Cloud technology can be used to query monitoring data on PC and mobile terminals. The force is transmitted downward through the upper bearing plate 1, the flat sliding plate 2, the intermediate steel lining plate 3, the pressure-bearing rubber pad 6 and the bottom basin 4. Its design has a large vertical bearing capacity range and can be applied to conventional bearings of various specifications.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A fiber optic grating force measuring support, comprising a pot-type rubber support, characterized in that, The pot-type rubber support is a movable pot-type rubber support. The movable pot-type rubber support includes an intermediate steel liner (3). The surface of the intermediate steel liner (3) is provided with a groove (61). The fiber optic grating force measurement system (5) is located inside the groove (61) and the fiber optic grating force measurement system (5) is encapsulated inside the groove (61).

2. The fiber optic grating force measuring support according to claim 1, characterized in that, The fiber Bragg grating force measurement system (5) includes a fiber Bragg grating force measurement component (51) and a protective cover (52), with the protective cover (52) disposed on the outside of the fiber Bragg grating force measurement component (51).

3. A fiber optic grating force measuring support according to claim 2, characterized in that, The fiber grating force measuring component (51) and the protective cover (52) are both located continuously on the periphery inside the groove (61).

4. The fiber optic grating force measuring support according to claim 1, characterized in that, The movable basin rubber support also includes an upper seat plate (1) and a bottom basin (4). The top surface of the intermediate steel liner (3) is provided with a flat sliding plate (2), and the top of the intermediate steel liner (3) is fitted with the upper seat plate (1). The top surface of the intermediate steel liner (3) is fitted with the bottom surface of the upper seat plate (1). The bottom basin (4) is provided with a pressure-bearing rubber pad (6) and the intermediate steel liner (3).

5. A fiber optic grating force measuring support according to claim 2, characterized in that, The protective cover (52) and the intermediate steel liner (3) are fastened together by bolts or by welding.

6. A fiber optic grating force measuring support according to claim 4, characterized in that, The inner diameter of the groove (61) on the surface of the intermediate steel liner (3) is less than or equal to the diameter of the planar sliding plate (2).

7. A fiber optic grating force measuring support according to claim 4, characterized in that, The bottom surface of the upper seat plate (1) is made of stainless steel, chrome-plated or polished.

8. A fiber optic grating force measuring support according to claim 1, characterized in that, The fiber optic grating force measurement system (5) can also be applied to a spherical support, and the fiber optic grating force measurement system (5) is set on the lower plate of the spherical support.

9. A fiber optic grating force measuring support according to claim 1, characterized in that, The pot-type rubber support is a fixed pot-type rubber support, and the fiber optic grating force measurement system is set on the outer periphery of the lower cylindrical structure of the upper plate to form a continuous fiber optic grating force measurement system.

10. A fiber optic grating force measuring support according to any one of claims 1-9, characterized in that, The fiber optic force measurement system can be manually monitored offline, and monitoring data can be queried on PC and mobile devices using cloud technology.

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