摘要
从时域Maxwell方程出发,考虑二维空间中的TM(横磁波)模型。利用基于时间域有限差分法(FDTD)和Yee网格剖分的GprMax2D软件,进行探地雷达反射特征模拟。通过模拟的探地雷达剖面图观察电磁波在不同介质处的反射特征,判断缺陷的位置。通过对钢筋、空洞和水三个混凝土构件中最常见的缺陷的数值分析,得到了不同介质分界面处的电磁反射特征,并对这三种介质在不同深度的反射强度进行比较,得到了不同介质关于深度及反射强度的具体函数关系,同时,对不同频率的雷克(Ricker)子波在这三种介质中可以探测的深度及分辨率进行了分析,得到了不同深度及不同性质的缺陷所需要的比较理想的中心发射频率。
It is started from Maxwell＇ s equations in time domain, TM model in two-dimensional space is consid- ered. By using GprMax2D software based on Finite Different Time Domain（FDTD） theory and Yee cells discretiza- tion method, reflection characteristic simulation of a Ground Penetrating Radar（GPR） is proceeded. The simulation results of GPR profile can reflect the characteristic of electromagnetic wave on concrete＇ s different defect or foreign bodies, which enables to judge the approximate location of defect. In numerical examples, according to cavity, wa- ter and reinforcement that appears most frequently in concrete, reflection characteristic of these different media is analyzed. Further analysis of reflection intensity of these three medium in the same and different depths, the func- tion correlation between depth and reflection intensity of each medium can be calculated. Besides, the center fre- quency of ricker source has been changed, which is assumed to simulate the GPR antenna, comparing with the de- tected depth and resolution of these three media, the adaptive center frequency desired by media with different property and depth is obtained.
出处
《黑龙江大学自然科学学报》
CAS
北大核心
2013年第6期819-826,共8页
Journal of Natural Science of Heilongjiang University
基金
国家自然科学基金资助项目(11226128)
中央高校基本科研业务费专项资金资助项目(DL12BB20)
东北林业大学大学生创新训练项目(201210225115)
