用解卷积同态滤波识别桩身单缺陷界面反射

IDENTIFYING THE REFLECTION WAVE FROM A SINGLE REFLECTION INTERFACE IN A PILE BY USE OF HOMOMORPHIC FILTERING TECHNIGUE

利用解卷积同态滤波 ,从桩顶反射波曲线的功率谱中分解得到频响函数 ｜H(f) ｜ ,在单缺陷界面反射条件下 ,根据｜H(f) ｜函数的基本特性可以确定反射系数及反射波往返时 ,进而确定桩身缺陷位置及缺陷严重程度 ,以实现桩身质量定量诊断的目的。给出了两根桩的桩身缺陷识别实例。

Using the homomorphic fitering technique,the function｜H(f)｜,which is called the norm of the frequency response function,is extracted from the power spectrum of the velocity response on a pile head.On condition that the pile has only a single reflection interface,the refection coeffcient and the back and forth of reflection wave can be determined according to the characters of the function｜H(f)｜.The size,the type and the location of a defect in the pile can be all identified well enough.Two practical examples are given to show the effectiveness of the proposed method.