Study On Application Of Beam Bridge Monitoring Based On The FBG Macro Strain Sensing Technology

During the service process of the bridge structure,the coupling effect of various external adverse factors will cause structural resistance decay.The failure of the structure will lead to the paralysis of the regional functions and a major disaster,which will bring huge losses to the lives and property of the people.Therefore,it is of great significance to establish a health monitoring system for the bridge structure.Sensing technology is the core technology of health monitoring system,the defect of traditional sensors has appeared in practical engineering applications.It is under such a background,fiber Bragg grating sensor to the light,flexible,high precision,anti electromagnetic interference,anti zero drift and other advantages come to the fore in the sensing field and become research hot spot of scholars at home and abroad.Fiber Bragg grating sensor adapted for the formation of macro strain sensor can measure a preset standard from the average strain,so that the measurement range is far greater than the conventional point sensors,only a few sensors can be arranged on the structure of the monitoring information of macroeconomic control.Based on this,this paper studies the application of fiber Prague grating macro strain sensor in health monitoring.The specific contents of this paper are as follows:(1)State the background and significance of the subject,the research and development of fiber grating sensing technology at home and abroad;(2)The fiber optic sensing technology and fiber Prague grating sensor are introduced.The fiber Prague grating macro strain sensor and the parameters of the parallel Topology Distribution in the main bending unit are introduced;(3)The fabrication process of the fiber Prague grating macro strain sensor is studied.The macro strain sensor has been successfully fabricated,and its stability and accuracy are verified;(4)For the conventional beam bridges design T-shaped reinforced concrete simply supported beam monitoring tests: through cell division of the beam,respectively in each unit for sensor placement in a parallel topology.From three aspects of vehicle speed,line shape and neutral axis,the monitoring of the beam is realized: in the monitoring of vehicle speed,the basic principle of the line is determined by the length of the two macro strain sensor;In the monitoring of the lineshape and neutral axes,the parameters of the parallel topology theory were transformed and combined with the external instrument monitoring and the actual test.