新疆地区LSAM-53柔性基层沥青路面典型结构车辙预估研究

Study on Rutting Prediction of Typical LSAM-53 Flexible Base Asphalt Pavement Structures in Xinjiang

摘要: 因新疆特殊气候下半刚性基层沥青路面车辙的病害问题，超大粒径沥青混合料LSAM-53凭借沥青用量少、骨架稳定性好等优势，本文提出以LSAM-53柔性基层替代传统半刚性基层以提升路面使用性能。通过考虑导致路面车辙的多项关键因素，构建了车辙预估模型并使用有限元软件模拟车辙板在不同轮压(0.5 MPa, 0.7 MPa, 0.9 MPa)和温度下(50˚C, 60˚C, 70˚C)的剪应力分布，明确了剪应力与轮压的直接关系。通过室内车辙试验，研究分析了不同级配(A, B)、温度(50˚C, 60˚C, 70˚C)和轮压条件下(0.5 MPa, 0.7 MPa, 0.9 MPa)的车辙变形规律，得出骨架结构更密实的级配车辙变形量更小，且温度和轮压对车辙变形有显著影响。基于试验数据和SPSS回归分析，研究建立了改进的车辙预估模型，并通过行驶速度修正，使其适用于实际行车条件，能够根据交通参数、路面结构与材料参数预估LSAM-53柔性基层在设计年限内的车辙深度，或反算动稳定度容许值以优化路面结构设计，为新疆地区柔性基层沥青路面的设计与应用提供了科学依据。

Abstract: In Xinjiang’s unique climate, semi-rigid base asphalt pavements often suffer from diseases. This paper suggests replacing the traditional semi-rigid base with a LSAM-53 flexible base, which is a super-large aggregate asphalt mixture with less asphalt use and better skeleton stability. The study builds a rutting prediction model by considering key factors causing rutting. Using a finite element software, the simulation of the shear stress distribution of a rutting board under different wheel pressures (0.5 MPa, 0.7 MPa, 0.9 MPa) and temperatures (50˚C, 60˚C, 70˚C) shows a direct link between shear stress and wheel pressure. Indoor rutting tests under different gradations (A, B), temperatures (50˚C, 60˚C, 70˚C), and wheel pressures (0.5 MPa, 0.7 MPa, 0.9 MPa) reveal that denser-structured gradations have smaller rutting deformations, with temperature and wheel pressure significantly affecting rutting. Based on test data and SPSS regression analysis, an improved rutting prediction model is established and corrected for driving speed, making it suitable for real conditions. The model can predict the rut depth of the LSAM-53 flexible base within the design life based on traffic, pavement, and material parameters, and it can also calculate the allowable dynamic stability value to optimize pavement design, offering a scientific basis for designing and applying flexible base asphalt pavements in Xinjiang.