Appendix F 3.3 Design Voids Factor
The Design Voids Factor is now calculated by Equation 5.
| Design voids factor, VF = Vf + Va + Vt | 5 | |||
| where | ||||
| Vf | = | basic voids factor | ||
| Va | = | adjustment for aggregate shape | ||
| Vt | = | adjustment to basic voids factor for traffic effects |
If adjustments for aggregate shape and traffic effects result in a reduction in basic voids factor of 0.04 L/m2/mm or more, special consideration should be given to the suitability of the treatment and possible selection of alternative treatments.
Selection of an alternative type of treatment should be considered where the design voids factor is at, or close to, the minimum recommended value of 0.10 L/m2/mm. For example, use of a polymer modified binder to aid aggregate retention or a double/double seal to provide a more robust treatment.