基桩质量纵波扭转波综合分析法可行性研究

Feasibility Research on Synthesis Analysis Method of Longitudinal Wave and Torsional Wave in Pile

为了论证纵波扭转波综合分析基桩质量的可行性,通过理论分析和动力有限元分析得到了三维状态下纵波和扭转波的传播特性,并对基桩质量纵波扭转波综合分析法进行了实际工程验证。结果表明:纵向荷载激励时,桩顶的接收波中不但含有纵波成分,还含有横波成分;扭转荷载激励时,桩顶的接收波中不但含有扭转波成分,还含有弯曲波成分,且扭转波属于横波,其波速小于纵波波速;在相同条件下,与纵波相比,扭转波的分辨率高,测试盲区深度小,对桩身的浅部缺陷更敏感,能较好地解决纵波测试中无法辨识出桩身浅部缺陷的难题;该方法能够应用于实际工程。

In order to demonstrate the feasibility of the synthesis analysis of longitudinal wave and torsional wave for the quality of pile, through theoretical analysis and dynamic finite element analysis, the propagation characteristics of longitudinal wave and torsional wave under three- dimension were found out. The synthesis analysis method was also verified by practical engineering. The results show that under longitudinal load there are longitudinal wave and transversal wave in pile top, under torsional load there are torsional wave and flexural wave in pile top, and the torsional wave is a kind of transversal wave. The wave velocity of the longitudinal wave is larger than that of the torsional wave. Compared with the longitudinal wave under the equal conditions, there are higher resolution and smaller testing blind area for the torsional wave, and the torsional wave is more sensitive to the shallow small defects in pile and can better detect them. This method can be applied to practical engineering.