Experimental Study of Deformation Measurement of Bored Pile Using OFDR and BOTDR Joint Optical Fiber Sensing Technology

Abstract

Pile foundation is the most common foundation form in geotechnical engineering; it is very important for engineering safety. In order to accurately grasp the deformation of pile foundation, OFDR (optical frequency domain reflectometer) and BOTDR (Brillouin optical time domain reflectometer) optical fiber sensing technologies are used to measure the strain variation of pile foundation. The measurement results of the two technologies are analyzed, and different data processing methods are used. The ability of the two methods to measure the strain of pile foundation is evaluated. The results show that OFDR technology can achieve high-precision and distributed measurement of strain of pile; BOTDR technology can achieve the monitoring effect of OFDR to a certain extent using appropriate data processing methods; the combination of the two methods can make up for the shortcomings of the short monitoring distance of the OFDR technique and the low accuracy of the BOTDR technique; by comparing the application effect with the two technologies in geotechnical engineering, the application prospect of OFDR–BOTDR joint optical fiber sensing technology in geotechnical engineering is discussed.

Activation Function Dynamic Averaging as a Technique for Nonlinear 2D Data Denoising in Distributed Acoustic Sensors

“…Each of them must be identified by frequency and spatial coordinate. Together with other reflectometric methods that study slowly changing physical quantities in new materials and structures [17][18][19][20], distributed acoustic sensors for flaw detection problems form a complete understanding of the object's behavior in a wide range of external conditions [21,22]. Thus, in [21], distributed acoustic monitoring was used to study the operating regimes of a gas turbine.…”