Foundation pile deflection measurement method based on distributed fiber sensing technique

The invention relates to a foundation pile deflection measurement method based on a distributed fiber sensing technique. According to the foundation pile deflection measurement method based on the distributed fiber sensing technique, pile body deflection of a foundation pile can be obtained in real time, and stability of the foundation pile is monitored. The foundation pile deflection measurement method based on the distributed fiber sensing technique is characterized by comprising the following steps: (a) a group of sensing optical cables which are parallel to the axis of the foundation pipe and symmetrically arranged based on the axis serving as a center line are arranged on edges of the foundation pile; (b) by means of a Brillouin demodulation technique, compression strain and tensile strain of each section of the foundation pile under the action of horizontal load can be measured in real time; and (c) according to a formula shown in the description, deflection of each section of the foundation pile can be calculated. The method is used for the pile body deflection measurement of a steel pipe pile, a reinforced concrete precast pile, a reinforced concrete bored pile and other foundation piles.