半刚性基层沥青路面结构高速弯沉仪应用误差

为评估高速弯沉仪在半刚性基层沥青路面结构中的适用性，采用2.5D有限元方法建立高速弯沉仪移动荷载作用下路面结构数值模型，并评估其应用误差. 首先，利用两个前人研究成果验证2.5D有限元程序的可靠性；其次，对比了常用式、全厚式和半刚性基层3种典型沥青路面结构的弯沉斜率曲线，并总结了弯沉斜率特征；最后，针对半刚性基层沥青路面结构的高速弯沉仪应用误差予以评估. 研究结果表明:半刚性基层沥青路面结构弯沉斜率曲线存在多个峰值点；高速弯沉仪应用于半刚性基层沥青路面结构时，参照传感器读数不为0，将其应用于典型半刚性基层沥青路面结构时，因参照传感器误差引起的弯沉误差高达87.3%；为保证工程测试精度，高速弯沉仪应用于半刚性基层沥青路面结构时宜延长横梁长度至8.0 m. 

Application Error of Traffic Speed Deflectometer for Asphalt Pavement Structure with Semi-Rigid Base

In order to evaluate the applicability of traffic speed deflectometer (TSD) in asphalt pavement structure with semi-rigid base, the 2.5D finite element method is employed to establish a numerical model subjected to the moving load of TSD. Firstly, the reliability of the 2.5D finite element program is verified with two previous published results. Then, the deflection slope curves of the conventional, full-depth and semi-rigid base asphalt pavement structure are studied and compared with each other, and their characteristics are summarized. Finally, the applicability error of TSD for asphalt pavement structure with semi-rigid base is examined. Results show that there are multiple peak points in the deflection slope curve of asphalt pavement with semi-rigid base. When TSD is applied to typical asphalt pavement structure with semi-rigid base, deflection test error caused by reference sensor error is as high as 87.3% while the reference sensor reading is not 0. In order to achieve accuracy result, the length of rigid beam of TSD is proposed to be extended to 8.0 m.