(长沙理工大学 交通运输工程学院，湖南 长沙 410114)
(School of Traffic and Transportation Engineering, Changsha University of Science & Technology, Changsha 410114, China)
【目的】解决内置感知器件与沥青路面材料因模量差异大造成的变形不协调问题，提出考虑协同变形增强的内置感知器件与沥青路面一体化设计方法。【方法】以埋入式电阻应变传感器为内置感知器件，利用有限元软件建立融合内置传感器的沥青混合料结构模型，通过数值模拟与计算，以10.0%的应力差异率为评价指标，确立内置传感器的应力影响范围作为模量过渡区域；采用环氧树脂材料制作模量过渡区，并对模量过渡区力学性能进行试验评价；运用数字图像相关（digital image correlation, DIC）方法对内置感知器件的沥青混合料试件开展单轴压缩和四点弯曲加载下的力学响应试验，通过比较传感器实测响应值和DIC法测量结果之间的差异，分析模量过渡区对传感器与沥青路面协同变形增强的有效性。【结果】内置传感器会改变沥青混合料结构的应力分布状态，传感器的竖、横、纵三向影响范围为58 mm×199 mm×82 mm，环氧树脂材质的模量过渡区具有良好的力学性能，其弹性模量为沥青混合料的2.5倍，可在沥青混合料与感知器件之间形成有效的模量过渡区；在逐级压缩和弯拉受力下，设置模量过渡区使传感器测得的试件结构应变差均值分别降低了66.6%和65.9%，设置模量过渡区能显著提高内置感知器件实测响应的稳定性和有效性。【结论】在沥青混合料与感知器件之间设置模量过渡区，使之形成模量梯度过渡结构，是提升两者协同变形的有效手段；在实际工程应用中，协同变形增强一体化设计流程主要包括：模量过渡区范围确定、材料选择、性能评价及协同变形有效性验证。
[Purposes] This work aims to solve the deformation incoordination problem caused by the large modulus difference between the built?in sensing device and the asphalt pavement material, an integrated design method of the built?in sensing device and the asphalt pavement considering synergistic deformation enhancement was proposed. [Methods] Taking the embedded asphalt strain gauge as an example, the ABAQUS software was used to establish an asphalt mixture structure model with built?in sensors. Through numerical simulation and calculation, the stress difference rate of 10.0% was taken as the evaluation index, and the stress influence range of the built?in sensor was established as the modulus transition area. The modulus transition zone was made by epoxy resin material and its mechanical properties were tested and evaluated. Using digital image correlation (DIC) technology, the mechanical response tests of asphalt mixture specimens with built?in sensing devices under uniaxial compression and four?point bending loading were carried out. By comparing the difference between the measured response of the sensor and the measurement results of the DIC method, the effectiveness of the modulus transition zone on the synergistic deformation enhancement of the sensor and the asphalt pavement was analyzed. [Findings] The results showed that the built?in sensor would change the stress distribution of the asphalt mixture structure. The influence range of the sensor in the vertical, horizontal and vertical directions was 58 mm×199 mm×82 mm. The modulus transition zone of the epoxy resin material had good mechanical properties, and its elastic modulus was 2.5 times that of the asphalt mixture, which can form an effective modulus transition between the asphalt mixture and the sensing device. Under step?wise compressive and flexural?tensile loading, the strain difference of the specimen measured by the transducer was reduced by 66.6% and 65.9% respectively by setting the modulus transition zone, which indicates that the stability and effectiveness of the measured response of the built?in sensing device could be significantly improved by setting the modulus transition zone. [Conclusions] Setting modulus transition zone between asphalt mixture and sensing device to form modulus gradient transition structure is an effective means to enhance the synergistic deformation of the two. In practical engineering applications, the integrated design process of collaborative deformation enhancement mainly includes the determination of modulus transition zone range, material selection and performance evaluation, and verification of collaborative deformation effectiveness.