Study on the Dynamic Characteristics of Low-Frequency High-Stiffness Viscoelastic Damping Structures

Viscoelastic suspension systems serve as components essential for enhancing ride comfort and structural reliability in tracked bulldozers. However, traditional suspension-damping structures often exhibit high-stiffness and reduced-damping characteristics under low-frequency excitations, limiting their adaptability in complex off-road conditions. This limitation adversely affects the operational safety and comfort of tracked bulldozers, particularly in extreme terrains. This study employs an elastic modulus gradient design, combined with the hysteretic properties of viscoelastic materials, aiming to develop five rubber materials with varying elastic moduli and constitutive parameters for damping-layer applications. Through parametric modeling and finite-element simulations, we systematically analyzed both static and dynamic performance across these five configurations while investigating how damping-layer elastic modulus variations influence dynamic vibration-damping characteristics. The results demonstrate that the S-NR3-NR3-S configuration exhibits superior dynamic vibration-damping performance. Further analysis focused on this optimal configuration's stiffness characteristics and energy dissipation capacity under different harmonic excitations and maximum compression displacements. Finally, practical validation was conducted through static and dynamic performance testing of physical prototypes using a universal testing machine and electro-hydraulic servo-controlled instrumentation, based on operational conditions of high-power tracked bulldozers. The presented findings and methodologies establish a theoretical foundation for optimizing ride comfort in construction vehicles, demonstrating significant practical applicability and engineering value.