Cracking On

Cracking On

Proactive and Reactive measures to keep roads in top condition

If the recent spate of earthquakes has taught us anything, it’s that NZ roads and civil works are always going to be peppered with shakes. While there’s little we can do to prepare ourselves for the big ones, there’s plenty we can do to mitigate the effects – especially of the smaller quakes which cause frequent but minor damage to our infrastructure.

Ideally, you need a mixture of Proactive and Reactive tools…

A proactive plan might include fitting more seismic joints into roadways. This is a no-brainer for big jobs like bridge approaches, but what about all those small changes in substrate (such as concrete culverts and small bridges) that don’t warrant the inclusion of a massive steel plate?


Engineers are aware that even these small seams are magnets for subsidence and seismic shifts, and IKO has come up with a quasi-seismic joint incorporating a mastic asphalt patch. This involves placing a suitably wide bridging material over the seam, and covering with Permatrack Mastic Asphalt. This allows for some movement without cracking.

A reactive plan might be a robust crack repair programme, aimed at fast and effective resolution of issues.

Obviously fault lines and liquefaction will likely result in major repair initiatives, but even a small shake may loosen up ironworks, or create surface cracks which are an operational hazard. A general plan for dealing with trivial cracks as they appear will help maintain optimum road conditions.

The simplest form of repairs is an asphalt patch. Traditionally, this would be seen as a quick fix, as evidenced by the number of borderline dangerous fixes around ironworks on NZ streets and motorways. But advancement in polymer technology has given rise to specialized products such as IKO Permatrack, which can be installed in hours and offers a long term solution.


Permatrack is a refined polymer modified mastic asphalt composite which is ideal for motorways, roadways and heavy traffic areas such as building approaches or dockyards. It’s designed to enable crews to quickly and very effectively repair cracks and seams – especially when rejoining two different materials (such as ironworks, kerbing, or concrete pavements.

Although a relatively new product in NZ, Permatrack is BBA certified, and has an extensive track record in the UK spanning decades. For most repair work a 2-3 hour window is required to effect the repair, and the road surface will be safe for traffic hours after that.

And best of all, the repairs last years, or even decades. The UK motorways authorities can point to Permatrack Repairs made in 2001 which are still flush some 15 years later.

Permatrack is distributed in NZ by Neuchatel NZ. For the last 100+ years Neuchatel has been protecting tens of thousands of surfaces from deterioration caused by heavy machinery and the elements. In this time they’ve refined their products and services to be more durable, environmentally friendly and affordable – especially for large scale projects. For more information, click the links above, or call us on 09 441 4595

Key Resources:

IKO Permatrack – Ironworks/Crack Repair Documents