地质雷达信号谱能分析法在混凝土缺损探伤中的应用

摘要

地质雷达是一种广泛应用于混凝土浇注质量及缺陷检测的技术手段,但常规数据处理方法对微小和微弱的有用信号难以识别,还会造成异常解译的不确定性.基于单一介质频谱响应唯一性的特点,提出并详细介绍了地质雷达谱能分析的信号后处理技术及数据处理流程,通过对桥梁混凝土腹板的检测实践,提取计算空气目标介质的谱能强度进而判定混凝土内部密实程度及缺陷,与常规数据处理的雷达图像对比,发现了常规图像中尚未反映的浅层不密实和深部微小孔隙异常.结合网格状探测并重构目标体模型,经三维成像反演出蜂窝缺陷的空间分布、形态及影响范围,实现了混凝土浇注质量及内部健康状况诊断的目的,为加固处理提供借鉴.%The ground penetrating radar is a widely used technology for the pouring quality and defect detection of concrete,but it is difficult to identify usefully micro and weak signal by the conventional data processing method,and it can also cause the uncertainty for the interpretation of abnormality.Based on the unique characteristics of spectral response for the single medium,the signal post-processing technology of the spectral energy analysis about GPR is presented and the data processing flow is described in detail in this article.Through the practice of bridge concrete,the strength of spectral energy about air target medium was extracted and calculated,and then the degree of compactness and defects about internal concrete were determined.In the comparison with conventional GPR image,the shallow non-dense and deep micro pore which were not reflected in the conventional images have been found through this post-processing technology.Combined with the gridding detection and the reconstruction of target model,the spatial distribution,morphology and influence scope of honeycomb defects have been inverted by three dimensional imaging.It has not only achieved the diagnosis purpose of concrete pouring quality and internal health,but also has provided scientific basis for reinforcement treatment.