通过单天线雷达、天线阵雷达及自组双天线雷达等多种检测方法对比分析了雷达识别桥梁深层钢筋的情况。首先介绍了雷达检测钢筋的基本原理，其次通过自组双天线雷达验证了天线间距对深层钢筋检测效果的影响。通过室内制作缩尺钢筋混凝土试件模型，对比分析了三种雷达对深层钢筋检测的影响。结果表明：单天线雷达对深层预应力钢筋定位效果较差；自组双天线和商业天线阵设备均可在存有表层钢筋屏蔽的情况下，很好地探测深层预应力钢筋。因此，在深层预应力钢筋的检测中，可用自组双天线雷达代替昂贵的天线阵雷达设备，而且自组双天线雷达可控制收发天线的间距，灵活性更好、更具有工程实用价值。

A variety of detection methods, such as single antenna radar, antenna array radar and self-assembled double antenna radar, are used to compare their capacity to identify deep steel bar of bridge. Firstly, the basic principle of radar detection bar is introduced, and then the effect of antenna spacing on the detection effect of deep steel bar is verified by self-organizing double antenna radar. The effect of three kinds of radar on deep steel bar is analyzed by indoor production of reinforced concrete specimen model. The results show that the positioning effect of the single antenna on the deep prestressed steel bar is poor. The self-assembled double antenna and the commercial antenna array equipment can detect the deep prestressed steel bar in the presence of the surface steel bar shield. Therefore, the self-assembled double antenna can be used instead of the expensive antenna array radar equipment to detect deep prestressed steel bar, and self-assembled double antenna can control the spacing of transceiver antenna, whose flexibility is of better and more practical value.