This article provides a detailed step-by-step guide to applying the Sandwich System—from base preparation to the final top coat—while also addressing the importance of drainage systems to ensure long-term performance.
Before installing the running track surface, proper sub-base preparation and drainage are critical. A poorly constructed base will compromise the entire system.
1.1 Sub-Base Requirements
- Material: Well-compacted asphalt or concrete base.
- Surface Regularity: Level with a slope of 0.5–1% to allow water runoff.
- Strength: Adequate compressive strength to support loads without deformation.
- Perimeter Drainage: Open concrete or polymer channels around the track perimeter to collect surface water.
- Internal Drainage: Slot or pipe drains may be included under the track base for areas with high rainfall or poor soil percolation.
- Slope Design: The running track should slope gently (0.5–1%) toward drains to prevent water ponding.
- Connection to Main Drainage: All collected water should flow into municipal or stadium drainage systems.
The Sandwich System consists of multiple specialized layers applied in sequence:
Step 1: Base Primer Application
- Purpose: Promotes strong adhesion between asphalt/concrete base and polyurethane layers.
- Application: Roll or spray apply polyurethane-based primer.
- Curing: Allow primer to dry before proceeding.
- Material: Recycled black SBR (Styrene Butadiene Rubber) granules bound with polyurethane binder.
- Application: Laid using a paving machine or hand trowel to form a shock-absorbing base.
- Thickness: Typically 10–15 mm depending on system design.
- Function: Provides cushioning, force reduction, and base elasticity.
- Material: Polyurethane seal coat mixed with fine rubber powder.
- Purpose: Seals pores in the SBR base to prevent water penetration and ensures smoothness.
- Result: Creates a uniform, non-porous surface for the next layer.
- Material: Two-component polyurethane applied by squeegee.
- Thickness: Around 2 mm.
- Function: Smooth, seamless elastic layer that forms the "sandwich" between SBR base and EPDM top coat.
- Material: Colored EPDM (Ethylene Propylene Diene Monomer) granules broadcast into freshly applied polyurethane adhesive.
- Thickness: 3–4 mm.
- Application: EPDM granules are spread evenly across the surface, then excess granules removed after curing.
- Result: UV-resistant, anti-slip, weatherproof surface with long-term durability.
- Color Options: Traditionally red or blue, but available in multiple colors for lane markings.
- Material: Polyurethane or specialized track marking paint.
- Application: Applied using stencils for accuracy, ensuring compliance with IAAF/World Athletics standards.
- Superior force reduction and shock absorption.
- Enhanced comfort and injury prevention for athletes.
- Weather resistance with effective drainage integration.
- Long service life with proper maintenance.
- Compliance with international competition standards.
- Regular sweeping and washing to remove dirt and debris.
- Inspection of drainage channels to prevent blockages.
- Prompt repair of any surface damage.
- Reapplication of line markings when faded.
The Sandwich System Running Track offers a premium, competition-grade surface with excellent durability and performance. Successful installation depends not only on the correct application of each material layer but also on the integration of an efficient drainage system. With proper base preparation, systematic installation, and ongoing maintenance, a Sandwich System track can deliver world-class athletic performance for decades.