CN216275222U

CN216275222U - Real-time measurement device for vertical displacement of medium-small span bridge

Info

Publication number: CN216275222U
Application number: CN202122698109.5U
Authority: CN
Inventors: 梁真真; 曹子豪; 王鸿然; 郭攀
Original assignee: Zhengzhou University
Current assignee: Zhengzhou University
Priority date: 2021-11-05
Filing date: 2021-11-05
Publication date: 2022-04-12
Anticipated expiration: 2031-11-05

Abstract

The utility model discloses a device for measuring vertical displacement of a middle and small span bridge in real time, which comprises a measuring assembly and a data acquisition assembly, wherein the measuring assembly comprises a steel wire, a fixed pulley, a metal box and a bolt; the acquisition assembly comprises a pull rope type displacement meter and a fiber grating demodulator. One end of the device is fixed at a bridge measuring point by a bolt, the vertical displacement is converted into the horizontal displacement by the fixed pulley 1, the horizontal displacement is converted into the vertical displacement by the other end of the device by the fixed pulley 2 to be connected with the pull rope type displacement meter, and the pull rope type displacement meter is connected with the demodulator. The device is placed in an iron-clad box and fixed on a pier. The utility model solves the problem of mounting the bracket, and the device adopts a mode that one end is fixed, and the other end is tensioned instead of being fixed at two ends, so that the steel wire sag is kept constant when the length or deflection of the beam is changed by temperature change and creep shrinkage. The device has the advantages of easy operation, low cost and wide application range.

Description

Real-time measurement device for vertical displacement of medium-small span bridge

Technical Field

The utility model relates to a device for measuring vertical displacement of a medium-small span bridge in real time, and belongs to the field of monitoring of vertical displacement of medium-small span bridges.

Background

Modern transportation networks are developed day by day, and bridges are used as hubs of modern transportation and are very important for evaluating safety of the bridges. The bridge vertical displacement is an important index for reflecting the safety performance of the bridge, and the monitoring of the short-term and long-term vertical displacement of the bridge is an important problem of a bridge health monitoring system. In the existing service bridges in China, the middle and small bridges occupy half-wall Jiangshan of the total number of the bridges in China, and the health monitoring system which is used for the middle and small bridges in a complex mode has no economical efficiency and no actual operability, so that the establishment of a set of simple, easy-to-operate and low-cost vertical displacement monitoring system for the middle and small bridges has very important engineering value and practical significance.

At present, the commonly used devices for measuring the vertical displacement of the small and medium span bridges mainly comprise a heavy hammer method, a level direct measurement method, a dial indicator method, a communicating tube method, an image method and the like. The advent of these devices has driven the development of vertical displacement measurements for small and medium span bridges, but they still suffer from several drawbacks and drawbacks. Firstly, some methods are only suitable for measuring bridge structures with static datum points and cannot meet bridges with flowing riverbeds; secondly, some methods need to set up a special bracket, which increases the difficulty of the device; finally, some methods are greatly affected by external environments, such as temperature, weather, pressure, etc., which greatly reduces the accuracy of the measuring device.

Disclosure of Invention

Aiming at the characteristics of the small and medium-span bridges and the defects and shortcomings of the existing small and medium-span bridge vertical displacement measuring method, the utility model aims to provide the device for measuring the small and medium-span bridge vertical displacement.

Specific embodiments of the utility model: a vertical displacement measuring device for small and medium-span bridges comprises a measuring assembly and a data acquisition assembly; the measuring assembly comprises a steel wire, two fixed pulleys, a metal box and a bolt; the data acquisition assembly comprises a demodulator, a fixed base and a pull rope type displacement meter; one end of a thin steel wire rope of the measuring assembly is fixed on the bottom surface of the bridge through a bolt, the other end of the thin steel wire rope bypasses the fixed pulley and is connected with a pull rope type displacement meter of the measuring assembly, the pull rope type displacement meter of the measuring assembly is connected with a demodulator, and the pull rope type displacement meter is fixed on a support of the bridge through a fixing base.

Further, the wire is maintained on the same straight line while passing through the lower edge of the fixed sheave 1 and the upper edge of the fixed sheave 2.

Further, the steel wire connecting measuring point and the pull rope type displacement timing keep constant tension all the time.

Furthermore, the stay wire of the stay wire type displacement meter is released in advance for a certain length to be connected with the steel wire.

Further, the measuring assembly and the collecting assembly are fixed inside the iron box, and the rigidity and the weight of the iron box are ensured.

Further, the base of the pull rope type displacement meter is fixed on the iron box through a bolt.

Further, the iron sheet box is fixed on the bridge pier through expansion bolts.

Drawings

FIG. 1 is a schematic diagram of the apparatus of the present invention;

FIG. 2 is a schematic view of a fixed structure of the fixed pulley of the present invention;

FIG. 3 is a schematic structural view of a pull-cord type displacement meter according to the present invention;

FIG. 4 is a schematic view of the connection structure of the pulling rope and the steel wire of the pulling rope type displacement meter of the present invention.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Referring to fig. 1, the real-time measurement device for the vertical displacement of the small-span bridge comprises a fixed pulley 1, a fixed pulley 2, a steel wire 3 and a pull rope type displacement meter 4, wherein one end of the steel wire 3 is fixed at a measuring point A at the bottom of the bridge, the vertical displacement is converted into horizontal displacement through the fixed pulley 1 and is connected with the fixed pulley 2 to convert the horizontal displacement into vertical displacement, the fixed pulley is fixed on a metal case through a bolt, the other end of the steel wire is connected with the pull rope type displacement meter 4, the pull rope type displacement meter is fixed on the metal case 5, and the pull rope type displacement meter is connected with a fiber grating demodulator 6.

When the device is used specifically, firstly, the length of the required iron box is determined according to the distance between the measuring point and the pier, secondly, a hole is drilled in the iron box, and then, referring to fig. 2, the fixed pulley 1 and the fixed pulley 2 are fixed in the iron box according to the position of the drilled hole.

Referring to fig. 4, the pulling wire and the pull-cord type displacement gauge are connected together by a fixing device 7, the pulling wire is firstly inserted into one end of the fixing device, then the pull cord of the pull-cord type displacement gauge is inserted into the other end of the fixing device, and then the pulling wire and the pull cord of the pull-cord type displacement gauge are clamped by rotating two screws.

Referring to fig. 1, firstly, the pull rope type displacement meter is fixed on the iron box through a bolt, secondly, a pull rope of the pull rope type displacement meter is lengthened for a certain distance in advance, then, pull ropes connected through a fixing device respectively pass through a fixed pulley 2 and a fixed pulley 1, then, the pull ropes pass through an opening on the upper portion of the iron box and are fixed at a point to be detected of a bridge, and finally, the whole iron box is fixed at a pier of the bridge to be detected.

After the whole device is installed, if the point to be measured generates downward vertical displacement, the fixed pulley 1 firstly converts the vertical displacement into horizontal displacement, then the fixed pulley 2 converts the horizontal displacement into vertical displacement again, then the vertical displacement generated by the point to be measured can cause the shortening of the pull rope type displacement meter, and finally the demodulator can acquire the displacement data shortened by the pull rope type displacement meter.

Vertical displacement data that the demodulation appearance was gathered can be through long-range storage in high in the clouds, can realize automatic and long-range real-time data collection function, and the vertical displacement of real-time supervision bridge structures changes, guarantees bridge structures's safe operation to provide reliable foundation for the safety assessment of bridge.

Claims

1. A real-time measurement device for vertical displacement of a middle-small span bridge is characterized by comprising a measurement assembly and an acquisition assembly, wherein the measurement assembly comprises a steel wire, two fixed pulleys and a metal bellows; the measuring component comprises a demodulator, a fixed base and a pull rope type displacement meter; the measuring assembly is characterized in that one end of a steel wire of the measuring assembly is fixed on the bottom surface of the bridge through a bolt, the other end of the steel wire is connected with a stay rope type displacement meter of the measuring assembly by bypassing a fixed pulley, the stay rope type displacement meter of the measuring assembly is connected with a demodulator, the whole device is fixed inside a metal box, the stay rope type displacement meter is fixed on the metal box through a fixed base, and the metal box is fixed on a pier through an expansion screw.

2. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the wire is maintained on the same straight line while passing through the lower edge of the fixed sheave 1 and the upper edge of the fixed sheave 2.

3. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the steel wire connecting measuring point and the stay wire type displacement timing keep constant tension all the time.

4. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the stay wire of the stay wire type displacement meter is released in advance for a certain length to be connected with the steel wire.

5. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the measuring assembly and the collecting assembly are fixed inside the iron box, and the rigidity and the weight of the iron box are ensured.

6. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the base of the pull rope type displacement meter is fixed on the iron box through a bolt.

7. The device for measuring the vertical displacement of the small and medium-span bridge in real time according to claim 1, is characterized in that: the iron sheet box is fixed on the pier through expansion bolts.