Semi-closed single communication pipe type bridge deflection test device and method

Abstract

The invention provides a bridge deflection monitoring device and a method. A non-deformation part of an abutment is set as an initial measuring point, then each girder measuring point is arranged in turn along a deformed girder, a measuring point device mounting bracket at each measuring point is fixed with a same gas column adjuster, the initial measuring point is not provided with a liquid column adjuster, the measuring point device mounting bracket at each measuring point of each girder is fixed with the same liquid column adjuster, the front end of each branched communicating pipe injected with liquid is connected to the gas column adjuster of a prior measuring point and the back end thereof is connected to the liquid column adjuster of a next measuring point, each gas column adjuster is connected to one pole of an air pressure difference sensor of respective measuring point through a connecting pipe, and each air pressure difference sensor is fixed on the measuring point device mounting bracket of respective measuring point, transmits test data to a data acquisition system through a signal transmitting device, and converts the test data into a deflection value of each measuring point of a bridge according to a conversion relation between pressure and deflection.

Description

technical field [0001] The invention relates to a device and method for testing bridge deflection, which is suitable for static and dynamic deflection tests of multiple control measuring points with any bridge span length and any slope, and belongs to the technical field of bridge detection and monitoring, in particular relates to bridge detection A high-precision and high-efficiency bridge static and dynamic deflection testing device and method in the process of health monitoring. technical background [0002] In the process of bridge inspection and health monitoring, the deflection value and alignment status of the bridge are an important evaluation parameter, which has important theoretical value for evaluating the long-term and transient operating state of the bridge structure and testing the real mechanical characteristics of the bridge. Therefore, the precision and accuracy of deflection measurement is very important; at the same time, bridges in the operation period g...

AI Technical Summary

Problems solved by technology

In the current bridge inspection and health monitoring process, the bridge deflection test generally adopts the following methods: 1. Use optical measuring instruments such as level gauges to measure bridge deflection. Although the operation is simple, the measurement accuracy is low, especially when bridge inspections are often carried out at night. The measurement results are greatly disturbed by human influence, and the error is relatively large. Moreover, when the longitudinal slope of the bridge is large, the operation needs to be turned, and the work efficiency is very low.

2. The deflection of the bridge is tested with displacement meters such as dial gauges and dial gauges. Although the accuracy is high, the installation of the fixed base is inconvenient, and data collection is difficult, and the work efficiency is slightly low.

3. Using the photoelectric image principle, the deflection value of the bridge is obtained through the collected image signal and the data processing method, such as the patent number ZL200610095083.2, the authorized announcement number CN100395515C, and the name "tension line video deflection measuring device and method" ", as well as an invention patent application with application number 200710103777.0, publication number CN101055218, and titled "Bridge Deflection and Displacement Monitoring Device and Monitoring Method". Restricted conditions, difficult data processing, and high cost, especially when testing at night, the actual operability is poor

4. Based on the principle of the connecting device, the deflection of the bridge is directly measured according to the change of the liquid level in the open connecting pipe. When the longitudinal slope of the bridge is large, a connecting pipe is usually connected between every two measuring points. The principle of this method is simple , but the actual test results show that due to the viscous resistance between the liquid and the pipe wall and the capillary action between the water and the pipe wall, the test accuracy is not high, and there is a large error in the zero reading after unloading. Due to the surface tension of the liquid, the liquid surface is non-horizontal, and there are large errors in the readings

5. Based on the principle of the connector, directly convert the deflection into the pressure of the liquid in the pipe, and use a pressure transmitter to convert the pressure change into a change in deflection. For example, the patent number is 200310108447.2, the authorized announcement number is CN100385201C, and the name is "Large-span Bridge Deflection monitoring method" is an invention patent, the method is theoretically feasible, but in the actual operation process, especially when the bridge span is large or there are many measuring points, due to the relative flow between the liquid in the pipe and the pipe wall, viscous resistance will be generated. There will be a certain degree of loss in the pressure of the liquid, resulting in a certain error in the measurement accuracy, and it only has a certain practical value in long-term bridge monitoring, and its cost is high in the bridge inspection process. However, it is difficult to install the device on site

Therefore, the existing bridge deflection testing device has the following defects: 1. Low test accuracy and large error; 2. The installation of the test device is complicated, data collection is difficult, and work efficiency is low; 3. The practicability is not strong, the operation is difficult, and the cost is high

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