Repair of interface cracking

S12.3.3

Cracking along the interface of a reinstatement must be repaired in accordance with the following:

Crack sealing systems must have a current Product Acceptance Scheme certificate.
Hot or cold applied systems may be used, subject to manufacturer’s recommendation on application under the prevailing weather conditions.
Treatments must be black in colour, unless otherwise directed by the authority.
The minimum PSV of the repair system surface is as specified for the type of surfacing (see S2).
The initial skid resistance must be >55 SRV as measured by the pendulum tester using the narrow slider in accordance with BS EN 13036-4.
Installation and Quality Control Procedures for all systems must be in accordance with the Product Acceptance Scheme certificate. The results of all quality control checks carried out on site and quality assurance information must be compiled in accordance with the requirements of the Product Acceptance Scheme certificate.
Preparation must be in accordance with the installation Method Statement and must include cleaning and removal of debris and contamination with a hot air lance. The substrate must be dried fully before applying the crack treatment.
Depending on the width of the crack an appropriate sealing system must be chosen:
1. Cracks between 2.5 and 5 mm wide must be repaired with an overband sealing system, as described in S6.8.8.
2. Cracks between 5 mm and 20 mm wide must be repaired by infilling it with a flexible bituminous sealant and then applying a surface sealing band up to 200 mm wide.
3. Cracks widths over 20 mm require a surface repair, as follows:
  1. The surfacing materials must be removed to the full depth of the surface course or to 40 mm, whichever is the lesser, for the full length of the crack or for 1 m length, whichever is greater. If the crack extends into the binder course layer, the affected materials must be removed and replaced in accordance with S6.4.
  2. Surfacing materials must be removed over sufficient width to ensure that the repair patch extends beyond the edges of the crack by a minimum distance equal to the nominal thickness of the replacement surface course. The minimum width of the repair patch is 100 mm.
  3. Inclusion of a geosynthetic material at the base of the repair patch could assist in limiting any reoccurrence of cracking.
  4. The replacement surface course patch must be laid in accordance with S6.4.
Where, as a result of an undertaker’s works, a crack requiring repair in accordance with S12.3.3 exists within 300 mm of another similar crack repair, the intermediate area must be included in the new repair.