Rail transit noise barriers are specialized acoustic structures designed for the unique noise characteristics of rail transportation. Unlike ทางหลวง barriers, rail barriers must handle wheel-rail interaction noise (especially on curves), braking squeal, engine/motor noise, and the air-pulse effect of high-speed trains in tunnels.
## Rail Noise Characteristics
Rail noise differs from road traffic noise:
- **Wheel-Rail Squeal**: High-frequency (2000-8000 Hz) on curves — extremely annoying. Requires high-NRC barriers.
- **Impact Noise**: At rail joints and switches — impulsive, broadband.
- **Engine/Motor Noise**: Continuous low-frequency rumble from propulsion.
- **Aerodynamic Noise**: At >200 km/h, air turbulence dominates — broadband hiss.
- **Ground-Borne Vibration**: Low-frequency (20-100 Hz) transmitted through ground — barriers don't help but resilient mounts do.
## Specialized Design
- **Vibration-Resistant Mount**: แผงs mounted on rubber isolation pads — prevents structure-borne vibration transmission through posts
- **Higher NRC Required**: NRC 0.90 (vs 0.85 for ทางหลวง) — absorbs more high-frequency squeal
- **Curved-Top Design**: Optional J-shaped or Y-shaped top improves diffraction edge effectiveness by 2-3 dB
- **Transparent Sections**: PC (polycarbonate) panels in station areas for visibility — NRC 0.10 but STC 30
- **Anti-Graffiti**: Optional anti-graffiti coating on station-area panels
## Key Advantages
- **Rail-Specific**: Tuned for wheel-rail noise spectrum. Standard ทางหลวง barriers insufficient.
- **Vibration Isolated**: Rubber mounts prevent rail vibration from transmitting through barrier structure.
- **Curved Top Option**: 2-3 dB additional reduction vs straight top — critical for tight noise limits.
- **Transparent Sections**: PC panels at stations maintain visibility and passenger safety.
- **Aerodynamic**: Smooth profile for high-speed rail — no turbulence generation.
- **Durable**: 30+ year life. Resistant to rail dust, brake dust, and weather.
## Technical Specifications
| Parameter | Value |
|-----------|-------|
| แผง Height | 2.5m, 3.0m, 4.0m (custom) |
| แผง Width | 0.5m (standard) |
| แผง Thickness | 100mm |
| Outer Skin | 0.8mm perforated galvanized steel |
| Core | 50mm mineral wool, 100 kg/m3 |
| Inner Skin | 0.6mm solid galvanized steel |
| NRC | 0.90 (rail grade) |
| STC | 33 |
| Insertion Loss | 12-16 dB(A) |
| Mount Type | Rubber vibration isolation |
| Post Type | H-section steel HEB 100 |
| Post Spacing | 2.0m |
| Wind Load | 1.2 kPa (rail design — includes train pulse) |
| Transparent Option | 15mm PC panel, STC 30 |
| Top Design | Straight or curved (J/Y shape) |
| Fire Rating | A1 |
| Standard | GB/T 19889, EN 16272 |
## Applications
- **Metro Residential Sections**: Underground-to-elevated transitions near housing
- **Urban Light Rail**: Street-level and elevated LRT corridors
- **Intercity Railway**: Ballasted track through suburban areas
- **Elevated Viaduct Transit**: Metro and rail viaducts through urban areas
- **High-Speed Railway**: 250-350 km/h lines through sensitive areas
- **Station Platforms**: Platform screen doors and edge barriers
- **Depot & Maintenance**: Vehicle maintenance facility perimeters
## Packaging & Delivery
- **Packaging**: แผงs palletized with foam separators. Posts bundled.
- **Container Loading**: 20ft GP ~ 200-350 m2; 40ft HQ ~ 400-700 m2
- **Lead Time**: 15-25 days standard; 25-40 days curved-top custom
- **Shipping**: FOB Tianjin / CIF / DDP