Development Of New Pavement Stress And Interlayer Displacement Sensors Based On Fiber Bragg Grating Measurement Technology

With the development and maturity of fiber Bragg grating(FBG)sensing technology,sensors based on FBG technology are more and more used in the health inspection of large-scale civil structures.However,in the field of road engineering,sensors designed for road design and development are rare.The maximum main road engineering difficult to monitor the stress and displacement between layers,3D printing technology developed a new way for the maximum principal stress and the layer displacement sensor based on,and test the stability of the sensor and verified by a series of tests.3D printing is a technology that has developed rapidly in recent years.Using 3D printing technology to make sensors can be more efficient,economical,and implement some complicated designs.This paper first verifies the feasibility of using 3D printing technology to make sensors.Secondly according to the characteristic of maximum principal stress and the displacement between layers,design two types of new road sensors,then check its sensitivity,structural strength and other parameters in theoretical derivation.Finally,the sensors are printed and fabricated by 3D Technology.In the light of the sensor,the calibration test is carried out first,and the response in the simplest state of force is studied.For the wavelength shift problem in the experiment,the original design of the sensor is discussed,and the temperature compensation mechanism is improved.On this basis,the uniaxial compression test of the main stress sensor is carried out to find out the stability of the test under complex stress condition.Based on this,3 kinds of principal stress sensors with different thicknesses are redesigned to investigate the force of sensors with multi force angle.Then the embedment scheme of the sensors is worked out in detail.Finally,two sensors are measured in the field.The accuracy of the test under the stress state of the real pavement structure is investigated.Compared with the traditional pressure sensor,the response range of the main stress sensor is greater,and the test results are closer to the theoretical solution.