Experimental research and numerical analysis on fatigue and bonding performance of UHPC-PE-TPO bridge deck pavement materials

As a critical technology in long-span bridge construction, steel bridge deck pavement has been a focal point of study in recent years, particularly regarding fatigue damage and interlayer cracking of the pavement layer; to address these challenges, traditional UHPC (Ultra-High Performance Concrete) and TPO (Thin Polymer Overlay) were enhanced with a two-component polyurethane adhesive and corundum aggregate, reinforced with steel fibers and cement, forming a UHPC-PE-TPO composite bridge deck paving material, which was evaluated using a "UTM-30" fatigue testing machine to investigate the fatigue cracking behavior of four different thicknesses under varying fatigue temperatures and analyzed with ABAQUS and Python-based finite element simulations to understand the influence of TPO thickness, reinforcement conditions, and load positions on the bonding layer performance, revealing that the four composite structures exhibited excellent crack propagation resistance, reduced maximum surface tensile strain, extended fatigue life, and enhanced bonding performance, with reinforced UHPC-PE-TPO demonstrating substantial improvements in fatigue resistance and crack life at all test temperatures, while model validation confirmed that the novel composite paving system effectively reduced stress deformation in steel bridge deck structures, mitigating fatigue damage and interlayer cracking, and significantly lowering transverse shear stress, peak longitudinal shear stress, peak tensile stress, and interlayer slippage compared to conventional materials. Based on the results, the novel steel bridge deck pavement system with the UHPC-PE-TPO composite pavement layer can effectively address the issues of fatigue damage and interlayer cracking of the steel bridge deck pavement, and enhance the interlayer bonding performance. • UHPC-PE-TPO boosts fatigue/bonding in steel decks, ideal for long-span bridges. • UHPC-PE-TPO shows excellent crack resistance, with steel fiber/cement reinforcement increasing fatigue life ≥55.12%. • Thicker PE-TPO boosts fatigue resistance. BF-20's life +277.8% (15°C) & +338% (-10°C). • FEA proves UHPC-PE-TPO cuts deck stress/strain, slashing shear/tensile peaks vs traditional. • New UHPC-PE-TPO excels in bonding/load resistance/damage reduction but needs better low-temp & long-term durability.