地质雷达在埋置物截面形状和尺寸正演分析中的应用

Forward Simulation on Geometric Effect of Underground Buried Body Using Ground Penetrating Radar

地下埋置物的存在会对基础设施和建(构)筑物的施工建设和安全运行产生不利影响,准确地把握埋置物的定位、截面形状和尺寸等信息尤为重要。以重庆市三个典型的桥涵为例,总结归纳覆盖层物质、埋置物截面形状变化条件下的地质雷达图像的响应特征。同时,提出了一种通过图像衍射曲线的顶点坐标以及水平方向反射图像的变化为依据,确定截面范围的方法。为了验证所提出方法的有效性,将通过图像确定的数据与现场测量的数据进行了对比分析。结果表明,对于规则性的图形结果的吻合度较高。不规则的四边形具有一定的误差,不过,误差值仅有2 mm。所提出的方法具有简便、快捷、准确度较高等特点,有利于实际工程的应用。

Underground buried geo-body near or beneath built-up area may lead to sudden collapse of ground surface,thus detailed information of stratum structure is paramount for preventing damage and managing potential risk situation.To achieve this goal,forward simulation on geometric effect of three typical culverts in Chongqing were carried out,the response characteristics of geometric effect and filling condition were summarized through GPR profiles interpretation,and a methodology for determining anomaly size was proposed by the apexes of diffraction hyperbolas and lateral changes in the reflection pattern.The comparison between GPR profiles interpretation result and was used to verify the validity of the proposed method.