关键词: 打桩, 布拉格光纤光栅（FBG）, 布里渊散射光时域分析技术（BOTDA）, 分布式监测, 数据处理

Abstract: In the construction process of pipe pile, the pile blasting or crack diseases often appears. The real-time dynamic sensing monitoring technology of quasi-distributed fiber Bragg gratting(FBG) and distributed sensing monitoring technology of Brillouin optical time domain analysis(BOTDA) are applied to pile driving into soil layer monitoring. The data processing method of distributed optical fiber sensing(DOFS) technology is proposed; the pile driving processing model experiment was designed. The experiment results show that: the FBG sensor can be well used to dynamically monitor the strain variation characters in the process of pile driving; it also can reflect the strain variation rules in pile different parts varied with soil depth; BOTDA distributed optical fiber sensor can monitor the pipe pile body strain variation characteristics during pile adaption (suspended) when driving; according to the strain changes, it can be used to analyze the eccentric loading level and estimate whether the pile cracks and fails, etc; research on the pile-soil interaction rules in the process of driving. The experiment results also show that: the combination of FBG and BOTDA optical fiber sensing monitoring technology in the monitoring quality of piles driving into soil layers has the more advantage; the combined technology has wide application prospect.

Key words: pile driving, fiber Bragg gratting(FBG), Brillouin optical time domain analysis (BOTDA), distributed monitoring, data processing