Avijohn Contracting uses HAMM oscillating compaction rollers on the Cahill Expressway.
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HAMM OSCILLATION TECHNOLOGY IS HELPING ASPHALT CONTRACTORS ACROSS THE COUNTRY ACHIEVE MAXIMUM COMPACTION ON SENSITIVE JOBS WHILE USING COMPLEX ASPHALT MIXES.
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s one of the great vantage points for Sydney’s New Year fireworks, the Cahill Expressway is situated right in the heart of town. Fittingly, it sits directly over a railway line with enough height to get an unspoiled view of the Sydney Harbour spectacle. When the road was in need of resurfacing in early 2019, the successful contractor was required to minimise noise and vibrations during works. The Cahill Expressway runs directly through Circular Quay and is suspended over the main train lines in the CBD, so
works were undertaken at night. As a result, noise and vibration needed to be low to minimise any disruptions to the surrounding people and not damage buildings or structures. Following similar experiences with sensitive compaction projects, Avijohn Contracting was tasked with undertaking the asphalt re-sheeting the expressway. Michael Kennedy, Operations Manager at Avijohn, knew traditional vibratory rollers would not be able to adequately minimise noise and vibrations on the project, so he turned to another model.
In the oscillation drum, two imbalanced shafts rotate in sync. They force the drum to rotate rapidly in a backwards-forwards movement, never leaving the ground. 28
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Having previously used HAMM oscillating compaction rollers on the Sydney Harbour Bridge, Avijohn Contracting now owns four oscillating rollers from Wirtgen Australia. To achieve similar success to that of the company’s works on the Harbour Bridge, Mr. Kennedy decided to use two oscillating rollers on the Cahill Expressway. Oscillating rollers can minimise noise and vibration impacts, which was a huge enabler for Mr. Kennedy when tendering for bridge works and the expressway. “When we do work in towards the city around buildings, councils can get
Inside the vibration drum, a rotating imbalance weight forces the drum to move up and down quickly, often losing contact with the ground entirely.
