Archive
Grasscrete – Paving the way to a sustainable future?
Recently, whilst working on a small access road I was introduced to what I thought was a novel, sustainable and simple paving solution – Grasscrete. After a cursory Google search, it transpires that it has been in existence since the 1970s- and indeed some of these uses are still standing. So what is it? And has anyone come across this before?
Simply put, it is a permeable pavement made up of recycled plastic formers and some steel mesh. Once installed some configurations claim to be able to carry weights of ~40T and use approximately 50% less concrete, with no need for active drainage. Relatively simple to assemble one can see why it would be attractive to a customer such as the MoD:
Less concrete means less water, less cement and ultimately less logistics – usually a major consideration when operating in austere environments.
Resistant to differential settlement – Acting as a monolithic slab, loads are uniformly distributed.
With much less run-off, grasscrete is more resistant to storms and stormwater run-off, not requiring active drainage.
Much more durable for expedient roadways and even HLSs for expeditionary theatre entry.
So what are the downsides?
More expensive than standard RC slabs
Plastic formers can be fragile – especially if left in hot temperatures or direct sun.
Lateral forces, especially from heavier vehicles braking/accelerating, may crush the narrower sections of the voids.
Rebar is at more risk from corrosion, minimum cover – especially if voids are filled with soil rather than quick draining gravel.
Whilst it may seem that I’m taking a commission from Grasscrete (c), perhaps Grasscrete/permeable pavements are something the Corps could look at? Whilst not structural and worth a TMR or two on its feasibility, I thought I’d sow the seed on this one…
I’d be keen to see if anyone else out there has seen this before and perhaps why its not been rolled out more often, especially for less trafficked areas/access roads etc. Without getting too far into the weeds…
Holdfast Training Services Trial Blog 