• Les Ellaby

Intelligent Hard Shoulders

Roadside Management and Erosion Control for longer lasting Roads

Integrated roadside management programs will need to be adopted because they combine the multiple missions of roadside vegetation control, roadside beautification, motorist safety, erosion control and preventative maintenance in one cost effective package.

Every year many accidents take place with cars getting off the road. When road shoulders are soft and or weak, wheels get caught in them and subsequently the drivers cause accidents trying to steer back onto the hard road surface. A possible solution for this is the hardening of the shoulders themselves.

There are various systems on the market to make shoulders safer; like grass-concrete tiles, shoulder asphalt, plastic shoulder plates or rubble. The aim is to create a hardened shoulder, on which it is unpleasant driving, but safe.

All these systems require (sometimes expensive) materials to be purchased and brought to site, whilst on-site there already is the basic material that you need: the soil.

Using RoadCem by PowerCem Technologies, and cement it is possible to stabilize the soft/weak shoulder to a hardened shoulder.

By using in-situ shoulder material with RoadCem and cement the original material is converted into a stable, impermeable but rough stabilization, which protects the highway pavement structure from erosion and water damage.

With a milling machine, with a width between 0.30 to 2.5 meter, the in-situ soil, the RoadCem and the cement are mixed to a depth of 20 cm. After compaction, a hard base is created. If required it is possible to cap this with approx. 2 or 3 cm of soil and sown with grass to create a green shoulder.

RoadCem technology has successfully been applied on many locations in the world, mainly as foundation for roads. Every soil type can be stabilized with high breaking strain and high fatigue resistance.

In addition to the high bearing capacity, an further advantage is the speed of construction. Obstructing traffic flow to a minimum, even with secondary roads, will be much appreciated by the client/users.

Gone are the days when roadside management meant just periodic mowing and spraying of weeds and a biannual regrading of the road shoulders. Integrated plans need to be incorporated that will require additional treatments or actions that over time will have a big impact on the system and ongoing expenses.

A stable water resistant roadside shoulder will reduce carriageway maintenance needs and costs, reducing erosion and improving water collection and reduce run off.

A strong roadside verge will maximize safety for vehicles and passengers and prevent water entering into the vulnerable road base/subgrade.

The primary objective in maintenance of roadside vegetation is to promote the safety of the highway user and preserve the highway infrastructure.

Very simply, roadside vegetation management involves caring for or controlling plants along the highway, the primary objective of providing a safe, unobstructed roadway corridor, and preserving the integrity of the highway infrastructure.

Vegetation, if left alone, can grow out of control and block visibility (signs, traffic, wildlife) which could endanger motorists.

Benefits of an Integrated roadside management programs:

• The use of a permanent stabilized soil shoulder will increase erosion control, road user safety and enable stormwater control constructions as design features to accomplish landscape objectives within the highway corridor;

• Development of additional ways to use plantings will reduce maintenance efforts and improve stewardship; and

• enhance existing partnerships and develop new partnerships with natural resource agencies and others to broaden benefits and to share knowledge and combine resources for mutual benefit.


· If drainage systems are not maintained, moisture will be retained in the roadside shoulders entering in and under road sub-base and pavement deterioration will take place.

· If a road agency is unable to maintain its drainage systems and these will be degraded with aggregate, sand, clay or dirt from the pavement structure itself, from material and refuse dumped on the pavement, and by mud and gravel washed down in the road. Then it likely will be better served by designing a road structure without a drainage system at all.


A car width stabilization of the existing pavement shoulder with RoadCem soil stabilisation technology can be quickly applied using just the existing soils, graded to follow the road camber. This will provide a long lasting maintenance free impermeable barrier preventing water from entering and destroying the road stone sub-base, at the same time funneling excess water further away from the road and providing a weed/plant free corridor and emergency vehicle standing/breakdown parking area.

#soilstabilisation #hardshoulders

11 views0 comments

Recent Posts

See All