Introducing technologies or methodologies in a sector that is heavily dependent upon standards, regulations and convention means it can be hard for the local government sector to innovate and create better and/or cheaper infrastructure solutions that ensures the community is served well.
If done in a controlled way, risks identified and contingencies at the ready, public infrastructure delivery can be readily transformed by engineers and infrastructure managers right across the state.
Warrnambool Airport upgraded it's gravel runway to a sealed runway three years ago and introduced a sealing technology (Otta1/GATT2 seal) that was half the anticipated cost of traditionally upgrading the runway surface to a sealed surface. The existing runway surface was a 40mm Class 2CR material that was more than adequate for the anticipated traffic, but had become uneven due to weathering, usage and the inability to grade the surface due to the 40mm material used. The largest single component was the reregulation of the entire top pavement layer to ensure a surface finish in line with CASA regulations (ponding of water). The cost of these works exceeded the available budget at the time.
Due to the need to seal the runway and the costing issue, alternative sealing methodologies were explored. With Asphalt being prohibitively expensive (but fixing the issue of ponding), GATT sealing was explored. A relatively little known technology in Australia, it is finding more widespread acceptance and usage by the Local Government sector due to the ability to seal low volume roads economically due to the ability to use existing sub-standard pavements. The technology induces bleeding through the application of 20mm graded aggregate deep into the pavement, creating a pseudo asphalt surface. The technology requires the bitumen to bleed (friction coefficient issues), traffic to bed the material in (low volumes being a runway) and can have aggregate up to 20mm ravel for up to six months on low traffic surfaces (foreign object issue for aircraft). For these reasons the seal on the face of it, entirely inappropriate as a technology for the required application - there was a reason this technology had never been used for an airport runway until now. The only redeeming feature was that the cost was only $7/sq. m.
My presentation will be about how to ensure you can successfully implement new ideas and technology in risk adverse organizations. Using methodologies learnt from previous pavement and seal trials, we were able to methodically implement a cost effective technology and the lessons learnt have now enabled us to create a works methodology and construction guidelines for a technology that could halve the cost of runway upgrades. This will now enable financially unviable business cases for rural and remote airstrips viable in the communities that need better transport connectivity the most.
References:
1https://www.aus-spec.com.au/wp-content/uploads/2021/03/NTN-GEN-026-Otta-seal-A-different-approach-for-road-sealing-1.pdf
2https://www.boral.com.au/gatt-surfacing