Surface wave-based nondestructive testing method and system for internal concrete state

Abstract

The invention relates to a surface wave-based nondestructive testing method and a nondestructive testing system for internal concrete state. The method comprises the steps of: 1) setting a measuring line on the surface of concrete to be tested, and setting n testing points on the measuring line; 2) setting a detector array on a straight line taking a first testing point as the center, and setting an elastic wave triggering device; 3) trigging an elastic wave through the elastic wave triggering device, acquiring the elastic wave through the detector, and transmitting the elastic wave to a data recorder through a cable; 4) moving the central point of the detector array to a next testing point, and repeating the step 3) till the testing is accomplished; 5) carrying out waveform processing on the data, and extracting and displaying a frequency dispersion curve of the surface wave; and 6) converting the frequency dispersion curve into a cross-section diagram so as to obtain the internal concrete state. The system comprises a data acquisition module, a data analysis module and a data visualization processing module which are connected in sequence. Compared with the prior art, the device and the method have the advantages of good precision, high efficiency, high detection degree, low cost and the like.

Description

technical field [0001] The invention relates to a method and system for non-destructive detection of concrete structures, in particular to a method and system for non-destructive detection of internal conditions of concrete based on surface waves. Background technique [0002] In recent years, with the development of large-scale infrastructure construction in my country, engineering quality accidents have occurred from time to time. Therefore, the quality inspection of geotechnical engineering, especially the non-destructive inspection of concrete structure engineering, is becoming more and more important, and the requirements for inspection are also getting higher and higher. The current nondestructive testing methods for concrete engineering structures mainly include rebound method, radar method, shock echo method, P wave velocity method and ultrasonic method. The rebound method is a commonly used non-destructive testing method for concrete, but the detection depth of this...

AI Technical Summary

Problems solved by technology

The rebound method is a commonly used non-destructive testing method for concrete, but the detection depth of this method is shallow, and it can only measure the average strength near the concrete surface, which cannot reflect the internal condition of the concrete, and the rebound value is highly dispersed, usually requiring more than 16 The effective rebound data is averaged, and the operation efficiency is low; the radar method can accurately locate the internal defects of concrete, but it is greatly affected by the shielding of low-resistivity materials such as steel bars, especially when the density of steel bars is high, it is difficult to obtain electromagnetic wave images behind the bars. Moreover, the radar cannot provide information on the strength; the impact echo method can measure the internal defects of the structure and the thickness of the components, but its longitudinal resolution is low, and the detection accuracy is greatly affected by the steel bars and water content inside the structure; the ultrasonic penetration test, although The longitudinal wave velocity of the material as a whole can be obtained, but it cannot be applied to structures such as tunnel linings that cannot be tested for cross-penetration; the P-wave velocity method can only measure the P-wave velocity of the concrete surface, and cannot detect the internal structure of the concrete

Although the above-mentioned non-destructive testing methods for concrete have their own strengths, their common weakness is that they cannot detect the mechanical properties deep inside the concrete, and it is difficult to meet the requirements of non-destructive testing of geotechnical engineering in large-scale infrastructure construction in my country.

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