Research on visualisation of plain concrete crack depth detection based on tracer and hand-held radar

ABSTRACT

Detecting the concrete crack depth has always been a technical problem. The traditional detection methods，which are based on stress wave theory, have limitations such as low accuracy, complex operation, time-consuming and laborious procedures. This paper proposes a new method based on the combination of tracer and hand-held radar to better complete this task. Its main procedures include firstly spreading tracer diffusion to the bottom of the crack propagation, and then mapping the location of the air-tracer interface by radar waves, thus visualising the crack depth information. This paper elaborates the detection principle of this new method, carried out the feasibility numerical analysis and simulation verification. Also, the concrete standard crack specimens were made, together with relevant experimental researches. As to the feasibility of the method, it is verified by using common distilled water and saturated sodium chloride solution as tracers. The detection effects of these two tracers are compared and analysed by comparing the test data with the actual depth of the specimen. This research innovatively applies tracers to actively improve the electrical ability of concrete cracks, and then uses radar to detect the electrical distribution of cracks, realising the visual detection of crack depth.

KEYWORDS:

• Plain concrete
• Crack depth detection
• Visualization
• Tracer
• Hand-held radar

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China (Grant No. 52109162), the National Key Research and Development Program of China (Grant No. 2021YFC3090104), and Fundamental Research Funds for Central Public Welfare Research Institutes (Y421007, Y421003)