光纤光栅传感器与沥青混合料间协调变形研究

Research on Coordinating Deformation Between Fiber Bragg Grating Strain Sensor and Asphalt Mixture

研究光纤光栅传感器与沥青混合料间协调变形性能是解决其在路面中应用的前提和基础。进行两者协调变形评价的试验设计,采用单轴压缩试验获取沥青混合料的粘弹参数,应用有限元软件ABAQUS进行三维数值模拟,分析高模量传感器的存在对于应力场、应变场分布和塑性变形的影响以及不同传感器模量对测试结果的影响。结果表明,高模量传感器的存在改变了其附近区域应力场和应变场的分布,但其未能对沥青混合料塑性变形的发展起到限制作用;应力场和应变场对于传感器模量均较敏感,传感器模量逐步减小使得其对测试结果的影响逐渐减弱;最终得出不同模量传感器对于应变场的影响曲线,以此作为后期测试数据修正的依据。

The research on the coordinating deformation between the Fiber Bragg Grating strain sensor （FBG） and asphalt mixture is the precondition and foundation to solve the application of the FBG in asphalt pavement. The testing method about the coordinating deformation between them was designed, the viscoelastic parameters of asphalt mixture was obtained by dynamic single axle-load creep test and a 3D finite element model with ABAQUS software was established to analyze the stress and strain fields redistribution close to the location of the FBG and the plastic deformation of asphalt mixture due to the existing of high-modulus FBG, and the influence of the modulus of the FBG on the strain and stress fields was discussed. The result indi- cates that the existence of high modulus sensor results in the redistribution of stress and strain fields, but it cannot limit the plas- tic deformation development of the asphalt mixture; the stress and strain fields are more sensitive to the modulus of the sensor, with the decrease of the sensor modulus, the influences on the result decreases gradually. At last, we may obtain the influence curve of the strain field under different sensor modulus and modified the measured information obtained by FBG to get the precise strain result.