It is a trend that the crack detection method of ballastless track slab changes from manual detection to high-speed vehicle detection. A crack detection method based on an infrared thermometer is presented in this paper. The basic principle of this method is introduced. This method is based on the fact that cracks cannot fill the field of view of an infrared thermometer. So the signal of the infrared thermometer is a mixture of cracks and track slabs. And it is separated by the angle coefficient in this paper. Simulations are carried out to study the influence factors of the detecting lower limit of crack width. And experiments are carried out to verify the correctness of the crack detection principle. The crack detection method can be used as a supplement to image processing to reduce the probability of missing detection.

无ball轨道平板的裂纹检测方法已从人工检测变为高速车辆检测，这是一种趋势。提出了一种基于红外测温仪的裂纹检测方法。介绍了该方法的基本原理。此方法基于以下事实：裂缝无法填充红外温度计的视场。因此，红外测温仪的信号是裂缝和轨道板的混合物。并用角度系数将其分开。通过仿真研究了裂纹宽度下限检测的影响因素。并通过实验验证了裂纹检测原理的正确性。裂纹检测方法可以用作图像处理的补充，以减少漏检的可能性。