Islam Kazi Moinul, Gassman Sarah L
Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA.
Materials (Basel). 2023 Jan 28;16(3):1126. doi: 10.3390/ma16031126.
This paper highlights the subgrade resilient modulus (M), which is recognized as an important parameter to characterize the stiffness of the subgrade soil for designing flexible pavement. In this study, 18 thin-walled Shelby tube samples of fine-grained subgrade soils were collected from two sites in South Carolina (Laurens/SC-72 and Pickens/SC-93) and tested in the laboratory using AASHTO T307-99 to obtain the M. In addition, falling weight deflectometer (FWD) tests were performed on the same pavement sections to obtain the back-calculated M per the AASHTOWare 2017 back-calculation tool. A subgrade M catalog was established and used to select hierarchical Input Level 2 for Pavement Mechanistic-Empirical design (PMED) analysis (v 2.6.1). The PMED analysis was run for 20 years. The Mechanistic-Empirical Pavement Design Guide (MEPDG) and global calibration values were used to predict asphalt concrete (AC) pavement distresses (e.g., rutting, bottom-up fatigue, top-down fatigue, and transverse cracking) and International Roughness Index (IRI) for each pavement section. The predicted values were compared to the field-measured values to determine bias and the standard error of the estimate to validate each distress prediction model for local calibration.
本文重点介绍了路基回弹模量（M），它被认为是表征柔性路面设计中路基土刚度的一个重要参数。在本研究中，从南卡罗来纳州的两个地点（劳伦斯/SC - 72和皮肯斯/SC - 93）采集了18个细粒路基土的薄壁谢尔比管样本，并在实验室中按照AASHTO T307 - 99进行测试以获得M值。此外，在相同的路面路段上进行了落锤式弯沉仪（FWD）测试，以通过AASHTOWare 2017反算工具获得反算的M值。建立了一个路基M值目录，并用于为路面力学经验设计（PMED）分析（版本2.6.1）选择分层输入级别2。PMED分析运行了20年。使用力学经验路面设计指南（MEPDG）和全局校准值来预测每个路面路段的沥青混凝土（AC）路面病害（如车辙、底部向上疲劳、顶部向下疲劳和横向裂缝）以及国际平整度指数（IRI）。将预测值与现场测量值进行比较，以确定偏差和估计的标准误差，从而验证每个病害预测模型以进行局部校准。
