通过多年的桩基检测实践,对低应变反射波法检测桩基的几个难点技术进行了深入研究。以一维弹性杆波动理论为基础,建立了基桩缺陷与反射波波形的关系,并对具有同样的同相反射或反相反射的缺陷以工程实测波形为例,从波形特征上阐明了缩径与离析、夹泥与空洞、局部断裂与断桩的区别,论述了桩顶浮浆层对波形曲线的影响、大直径桩的横向惯性效应以及不同桩型、不同桩底持力层的桩底反射波特征。从而能较好地避免缺陷的误判,对反射波法检测桩基完整性具有较大的借鉴意义。 Through many years of pile foundation inspection practice, several difficult techniques for testing pile foundation with low strain reflection wave method have been studied in depth. Based on the wave theory of one-dimensional elastic rod, the relationship between the defect of foundation piles and the waveform of reflected wave was established. Taking the measured waveform of the same in-phase reflection or anti-phase reflection as an example, And the difference between segregation, mud and void, partial fracture and broken pile, the effect of pile top floating layer on the wave curve, the transverse inertia effect of large diameter pile and the pile bottom of different pile types and different pile bottom holding layers Reflected wave features. Therefore, the misjudgment of defects can be avoided well, which is of great reference to the detection of pile foundation integrity by reflection wave method.