Numerical Exploration on Load Transfer Characteristics and Optimization of Multi-Layer Composite Pavement Structures Based on Improved Transfer Matrix Method

Transportation structures such as composite pavements and railway foundations typically consist of multi-layered media designed to withstand high bearing capacity. A theoretical understanding of load transfer mechanisms in these multi-layer composites is essential, as it offers intuitive insights into parametric influences and facilitates enhanced structural performance. This paper employs an improved transfer matrix method to address the limitations of existing theoretical approaches for analyzing multi-layer composite structures. By establishing a two-dimensional composite pavement model, it investigates load transfer characteristics and validates the accuracy through finite element simulation. The proposed method offers a straightforward analytical approach for examining internal interactions between structural layers. Case studies indicate that the concrete surface layer is the main load-bearing layer for most vertical normal and shear stresses. The soil base layer reduces the overall mechanical response of the substructure, while horizontal actions increase the risk of interfacial slip and cracking. Structural optimization analysis demonstrates that increasing the thickness of the concrete surface layer, enhancing the thickness and stiffness of the soil base layer, or incorporating gradient layers can significantly mitigate these risks of interfacial slip and cracking. The findings of this study can guide the optimization design, parameter analysis, and damage prevention of multi-layer composite structures.