Subgrade Stabilisation
& Fill Drying

Over the past three decades, Hiway Group has continuously developed and refined our subgrade soil stabilisation and stabilising solutions to optimise pavement design and deliver significant cost benefits for our clients throughout Australia and New Zealand.


Construction of new, and stabilisation of existing, pavement surfaces

Moisture conditioning of earthworks for residential subdivisions

Fill drying for extension of earthworks construction seasons

Stabilisation of subgrades for civil and infrastructure projects

Stabilisation of subgrades for industrial and commercial developments


Significantly improved in-situ subgrade stability

Subgrade strength gains of up to 20 times

Cost savings due to reduced requirement for imported aggregates, fewer transport costs and faster construction time

Reduces risk of costly subgrade pavement failures

A robust, durable platform for aggregate construction

Substantially reduces moisture susceptibility

Creates a more uniform pavement layer

Stabilised subgrade forms a soil particle and moisture barrier that protects overlying aggregate layers from upward migration of plastic fines

Dries large volumes of water-logged soil instantly

Can be carried out in poor weather conditions

Reduces down-time by enabling earthworks to continue immediately after wet weather

May enable reduced pavement thickness, providing significant cost savings

Subgrade Stabilisation

Hiway Group solutions have been used across a wide range of applications, from local authority roads to site works for land developers and major infrastructure projects for Government.

By stabilising a subgrade with specialised binders, we can cut aggregate requirements by more than 50% and reduce the amount of excavation needed during construction. Time and cost savings are realised through a moisture-resistant robust anvil for faster construction of overlying aggregate layers.

Fill Drying

Hiway Stabilizers pioneered the use of fill drying in New Zealand and we are actively developing its use with road authorities and land developers across Australasia.

As a highly effective way to combat wet soil, it enables earthworks to continue in adverse conditions and allows water-logged soils, to be instantly used. Fill drying also increases the strength of the subgrade substantially, reducing the requirements for cut to waste, enabling greater reuse of the existing on-site materials and reducing the need for imported aggregate.

Fill drying has significant benefits for subdivision land developers where the completion of earthworks to tight construction programmes is critical to section sales. It is also well suited to infrastructure projects where earthworks completion is critical to the civil works construction programme.

Hiway Stabilizers pioneered the use of fill drying in New Zealand.


As Australasia’s largest providers of specialist stabilising technologies, our expertise and commitment to innovation has seen us develop solutions that optimise material properties to make them ideal for the specific conditions we’re working in. We are equipped to tackle the most demanding of sites, achieving almost instantaneous results and maintaining high production outputs.

Cost & Carbon Calculator

Use Hiway Group’s carbon calculator to determine your potential carbon emission offsetting and cost savings.

Calculate Your Savings

Engineering & Design

Hiway Group is the only specialist stabilisation, recycling and reuse contractor in Australasia to provide extensive in-house design services.

From concept design to delivery, our team provides a ‘one-stop-shop’ for the design of recycled pavements, foam bitumen recycling, stabilising, pavement rehabilitation, heavy duty and overlay pavements.

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