Vibration and noise reduction components for urban rail transit
What are the main sources of vibration and noise in rail transit?
Wheel-rail rolling impact, rail corrugation, track structure vibration, vibration transmission between fasteners and bearing plates, and resonance in tunnel/bridge structures. Vibration propagates through the ground, causing building swaying, indoor noise, and interference with precision instruments.
What are the common grades of vibration-damping track structures?
General vibration damping: ordinary elastic fasteners; Medium vibration damping: elastic bearing plates, rubber floating plates; High-grade vibration damping: rubber floating plates, spring floating plates; Special vibration damping: steel spring floating plates (highest vibration damping efficiency). Different grades are selected for different areas to achieve "on-demand vibration damping."
What are the core performance indicators of vibration damping components?
Static stiffness, dynamic stiffness, dynamic-to-static stiffness ratio; damping coefficient (dissipates vibration energy); fatigue life, creep, aging performance; vertical, lateral, and longitudinal stiffness matching.
Why can low-stiffness bearing plates reduce vibration?
The lower the stiffness, the better the track elasticity, the smaller the impact, and the lower the vibration transmission. However, the stiffness cannot be too low, otherwise it will lead to: unstable track gauge, train swaying, rail displacement, and deterioration of component stress. A balance must be found between vibration reduction effect and operational stability.
Maintenance precautions for vibration-damped sections?
It is strictly forbidden to arbitrarily change the type of pads or fasteners; it is forbidden to arbitrarily thicken or thin the pad layer; regularly check for aging, deformation, and damage of elastic elements; immediately investigate the condition of the structure and components in case of abnormal vibration or noise.