A button-type bridge pier scour monitoring device based on Bragg grating sensor

Abstract

The invention discloses a button pier sour monitoring device based on FBG (fiber Bragg grating) sensors. The button pier scour monitoring device comprises a sleeve provided with a through hole, a sensor data collector located outside the sleeve and at least two monitoring units located in a cavity of the sleeve. Each monitoring unit comprises a button, an FBG sensor, a connecting plate and a bottom plate, wherein the bottom plate is fixedly connected to the inner wall of the sleeve, the connecting plate is fixedly connected to the top of the bottom plate, one end of the button is fixedly connected onto the connecting plate, the other end of the button penetrates through the through hole on the wall of the sleeve, and the FBG sensor is fixedly connected onto the connecting plate. The sleeve is hermetic. The monitoring units are axially distributed along the sleeve, and the FBG sensors of the monitoring units are connected through a same optical cable in series and are connected to a signal input end of the sensor data collector. The monitoring device can monitor whole process of scouring and backfilling in real time for a long term, monitoring data are accurate, and service life is long.

Description

technical field [0001] The present invention relates to a bridge pier scour monitoring device, in particular to a button-type bridge pier scour monitoring device based on a Bragg grating (full English name of Bragg grating: fiberBragggrating, abbreviated as FBG in the text), the monitoring device is especially suitable for Long-term real-time monitoring in flood-prone areas, records of the entire process of scouring and backfilling, and monitoring of better durability. Background technique [0002] Scouring disease of bridge foundation structure is one of the most important reasons for the function failure and loss of safety performance of today's bridge structures. Taking the United States as an example, from 1966 to 2005, 58% of the collapsed bridges in the United States (1502) were related to the scour of the bridge foundation structure. The US Department of Transportation has regarded the bridge foundation scour as a function of the highway bridge structure and one of t...

AI Technical Summary

Problems solved by technology

In fact, a variety of pier scour monitoring devices (such as based on radar and sonar technology) have been developed, but it is difficult to achieve effective long-term real-time monitoring. The monitoring period is easily affected by bad weather and the durability of the monitoring device itself is not high. It is impossible to observe the whole process of scouring including the backfilling of the river bed after scouring, and it is easily disturbed by debris in the river, and the results are unstable. In addition, monitoring cannot be carried out during floods, so it is mostly used for temporary scouring monitoring and cannot collect long-term data. Monitoring data to track and reasonably predict the scour depth of bridge piers

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