Cracks and deterioration in roads are an inevitable maintenance issue for local councils. Road shoulders in rural areas are particularly affected, partly by the way the road has been built.
Thirty years ago it was common practice for bitumen seals on roads to be laid only six or seven metres wide with the underlying pavement commonly being nine metres wide.
As a result of the narrow seal width, water can easily penetrate the pavement at the point where the heaviest wheel loading occurs. This causes breaks and cracks in the outer edges and shoulders of the pavement.
Many rural Australian roads were built this way and are susceptible to this kind of deterioration. Simply resealing the pavement does not address the ongoing maintenance and safety issues associated with damaged or uneven road edges.
Kempsey Shire Council in NSW identified these problems in its roads. Tony Green, Engineering Works Manager at the Council, says that fixing these issues often requires an excavator. This digs out and replaces a wide area of pavement to allow the use of heavy rollers and graders, even if the pavement deterioration is minor.
An innovative new piece of machinery now offers a more viable and efficient solution.
Nearly 18 months ago, Mr. Green was working with contracting company Stabilcorp, when the topic came up in conversation. Back then Stabilcorp had imported a skid-steer paver attachment, also called a pavement widener, from the United States. “It was really just a coincidence,” says Mr. Green. “This equipment became available at a time when we were looking for better solutions to this problem.”
The pavement widener can be attached to a skid-steer loader and used to widen the road and repair edge breaks to the road shoulders with asphalt or gravel where the deterioration has occurred. “The advantage is that you can deliver construction materials straight onto any excavated site,” he says. Only the damaged section of a shoulder of the road needs to be excavated, not a large area as previously required.
Where the underlying pavement is still good, a profiler can remove a sufficient depth of gravel on the outer edge of the road and replace it with asphalt or gravel in one pass using the paver attachment.
The advantages of using such an attachment for road maintenance is that it provides a neat edge to the existing seal and it’s much faster than conventional methods. The attachment runs on the sealed pavement and places the asphalt or gravel in the excavated area to the side and with minimal spillage. “It’s quite an impressive machine,” says Mr. Green.
“The new one is remote controlled and it takes the guys out of the danger area.”
It can lay to a depth of 300 millimetres and to a width of 1.5 metres, and it has a heated screed for use when laying asphalt.
The original pavement widener had a smaller hopper for materials and required the operator to control the attachment using levers, which put the operator in an unsafe position during the laying phase of the works. The ShoulderMaster, designed by Stabilcorp, is controlled by the operator via a hand-held remote, and complies with WHS & E requirements.
Mr. Green estimates that the ShoulderMaster does 100 metres of road widening in roughly 10 minutes. “It’s so much faster,” he says.
The Council has recently submitted its work with the ShoulderMaster to the Institute of Public Works Engineering Australasia (IPWEA) 2015 Engineering Excellence Awards.
While the ShoulderMaster has fit the bill for the Kempsey Shire Council, it has yet to hit the Australian market.
Stabilcorp will be officially launching the ShoulderMaster to the market later this year and Mr. Green anticipates that, provided councils are willing to give it a go on their roads and pavements, it has a definite market here in Australia.