A detection system design method for detecting the integrity of cast-in-situ piles based on dts

Abstract

The invention discloses a detection system design method for detecting the integrity of cast-in-situ piles based on DTS. A linear optical fiber is implanted into the pile body with a section radius of R and arranged along the center line of the pile, and the implanted optical fiber is used as an internal heat source to heat the pile. The critical radius affected by heat conduction is r0, and Ts is the temperature of the rock-soil medium. Under initial conditions, the temperature of the pile body and the outer surface is equal to the temperature of the rock-soil medium. Radius r0, the thermal conductivity k can be determined by the DRPL-II thermal conductivity tester. According to the known DTS instrument accuracy value δ, the optical fiber heating power q can be calculated through the formula. The present invention uses large-diameter concrete pouring pile defect detection as a research Object, determine the appropriate number of implanted optical fibers, calculate the critical radius r0 and heating power q, so that the design indicators in the DTS inspection process have a basis, can achieve fast and complete inspection, and promote the standardization of DTS inspection pile defects.

Description

technical field [0001] The invention relates to the layout design of temperature sensors for detecting the integrity of cast-in-situ piles based on heat conduction characteristics in the engineering field, and in particular to a detection system design method for detecting the integrity of cast-in-situ piles based on DTS. Background technique [0002] At present, low-strain method, high-strain method, ultrasonic transmission method, static load test, etc. are mostly used in the integrity detection of cast-in-situ piles. These detection methods have the disadvantages of low efficiency, heavy equipment, large volume, real-time remote monitoring, and high cost. [0003] The detection technology based on distributed optical fiber sensing and temperature measurement uses ordinary optical fiber as the sensing and transmission medium, without adding other external sensor devices, and it has a certain degree of flexibility, which can maintain a certain degree of bending and embed it...

AI Technical Summary

Problems solved by technology

However, there is still no theoretical basis for the arrangement of optical fiber sensors in cast-in-situ piles and the determination of related parameters.

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