Affiliation:
1. Materials & Structural Engineering Department, Nanjing Hydraulic Research Institute, Nanjing 210024, China
2. The National Key Laboratory of Water Disaster Prevention, Nanjing 210029, China
3. College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China
Abstract
Cracks are the most typical faults of concrete structures, and their extension can lead to structural fracture. However, when cracks develop inside a structure, the most important depth information is invisible and difficult to measure. The tracer electromagnetic method is an effective technique for detecting the depth of concrete cracks, but since concrete is a multiphase stochastic composite material, its complex internal structure often interferes with the radar detection results, making the conventional radar interpretation technique difficult. In this study, the detection results for concrete crack depth detection based on the tracer electromagnetic method were comprehensively analyzed by combining the complex signal analysis technique, using transient information such as amplitude, phase, and frequency in order to improve the precision and accuracy of radar signal interpretation. In this study, a numerical model was established to determine whether typical cracks such as vertical cracks and diagonal cracks contain indicators or not, and the ground-penetrating radar forward simulation software was used to perform forward simulation of the numerical model and analyze the forward results. The complex signal analysis technique was used to obtain the response characteristics of typical cracks when they did and did not contain the indicator, and the complex signal was finally analyzed by combining it with the actual crack depth detection data. The results show that the tracer electromagnetic method can significantly improve the crack bottom’s reflection ability for radar signals, and when the crack bottom contains an indicator, the amplitude of the reflected signal at the bottom of the crack is enhanced, the phase is reversed, and the frequency is reduced. The distribution of the crack morphology and the location of the crack bottom can be analyzed more conveniently by using the complex signal analysis technique.
Funder
the National Natural Science Foundation of China
Reference36 articles.
1. Liu, X., Chen, J., Wang, H., Jia, Z., and Wu, Z. (2023). Earthquake Economic Loss Assessment of Reinforced Concrete Structures Using Multiple Response Variables. Buildings, 13.
2. Seismic performance impacts of staircases in reinforced concrete frame structures under rarely occurred earthquake;Wang;J. Comput. Methods Sci. Eng.,2024
3. Damage analysis of a pseudoclassic reinforced concrete frame structure under the action of the Ms 6.8 Luding earthquake in China;Li;Structures,2024
4. Bai, Z., Liu, T., Zou, D., Zhang, M., Hu, Q., and Li, Y. (2024). Multi-scale image-based damage recognition and assessment for reinforced concrete structures in post-earthquake emergency response. Eng. Struct., 314.
5. Post-earthquake Performance Level Investigation of ACI-Based Designed Simplified Reinforced Concrete Structures;Arab;Iran. J. Sci. Technol. Trans. Civ. Eng.,2022