High-modulus polyester geogrid with bituminous coating for reflective cracking control in asphalt pavements.
Spalla Pet is Haizer's geogrid for reflective cracking control in asphalt pavements: a composite of high-modulus polyester grid, ultralight nonwoven geotextile and bituminous coating with a bitumen content above 65%. Installed between asphalt layers — or between asphalt and concrete pavement — it absorbs the stresses concentrated at the cracks of the old pavement and redistributes them, and can retard crack propagation into the new overlay by up to four times.
Spalla Pet uses high-modulus polyester: high flexibility, toughness, greater resistance to installation damage and thermal expansion compatible with asphalt.
| Property | Method | Spalla Pet 50 | Spalla Pet 120 |
|---|---|---|---|
| Grid raw material | — | High-modulus polyester (PET) | High-modulus polyester (PET) |
| Structure | — | Geogrid + ultralight veil | Geogrid + ultralight veil |
| Coating (bitumen content) | — | Bituminous > 65% | Bituminous > 65% |
| Nominal tensile strength (MD and CMD) | ABNT NBR ISO 10319 | ≥ 50 kN/m | ≥ 120 kN/m |
| Elongation at maximum force | ABNT NBR ISO 10319 | ≤ 12% | ≤ 12% |
| Tensile strength at 4% elongation | ABNT NBR ISO 10319 | ≥ 20 kN/m | ≥ 38 kN/m |
| Total mass per unit area | ABNT NBR ISO 9864:2022 | 300 g/m² ± 10% | 550 g/m² ± 10% |
| Mesh aperture | — | 40 mm × 40 mm | 40 mm × 40 mm |
| Grid open area | — | > 80% | > 80% |
| Residual strength after installation damage | DIN EN ISO 10722 | ≥ 48 kN/m (96% of nominal strength) | > 90% |
| Polymer softening / melting point | — | 190 °C / 255 °C | 190 °C / 255 °C |
| Max. recommended aggregate size | — | 20 mm | 20 mm |
| Standard roll (width × length) | — | 3.95 m × 100 m (395 m²) | 3.95 m × 100 m (395 m²) |
| Approx. roll mass | — | 120 kg | 215 kg |
Mechanical properties expressed as minimum average roll values (MARV). MD = machine direction; CMD = cross-machine direction. Mass per unit area and roll mass are identification values; the mass per unit area includes the bitumen absorbed by the carrier veil. Spalla Pet can be supplied in other strengths, according to design and scheduled delivery.
