The demonstration allowed the attendees to inspect a Rob Carr slurry microtunnelling machine as it installed a DN 1,000 HOBAS Jacking Pipe on Queensland Urban Utilities’ (QUU) Deebing Creek Trunk Sewer Main Project.
QUU Project Manager Senthi Nathan co-ordinated the event with HOBAS Executive Director Andy Holman, Rob Carr Construction Manager Brett Everard and Rob Carr General Manager Angelo Soumboulidis. Mr Nathan said the demonstration provided a valuable opportunity for QUU employees to both learn more about the minimally invasive technique of microtunnelling, and see a project many of the attendees had worked on come to fruition.
The project marks the inaugural use of HOBAS pipe on a microtunnelling project with QUU, a particularly noteworthy event considering alternative pipe was originally planned for the project. Mr Holman told Trenchless Australasia that the manufacturer who was originally going to supply the pipe fell through unexpectedly, at which point HOBAS stepped in and was able to provide the DN1,000 HOBAS pipe in a very short turnaround time.
QUU Senior Business Analyst Kaela Smith said she had taken a lot away from the demonstration, and due to her role in managing project costings, was particularly interested in Mr Holman’s presentation on the HOBAS pipe. She was previously unaware that HOBAS pipe provides a more competitive price at larger nominal diameters, compared to clay pipe, and said she would be taking this new learning back for future projects.
SMEC, who were contracted by Rob Carr to undertake the design component of the project, said there were significant issues to consider when designing the project. SMEC Water Resources Engineer Scott Dicker told Trenchless Australasia that the property is on land that is a cultural heritage site for Indigenous Australians, as well as in an area with native fauna that had to be taken into consideration.
Mr Soumboulidis said Rob Carr was able to provide a novel design solution to the land restrictions by extending individual pipeline lengths. This technique was able to provide the most cost efficient construction method for QUU.
Mr Nathan said he was very pleased with how the demonstration went, and is very positive about the project. He said the project is very significant due to being 100 per cent trenchless, which has allowed the new infrastructure to be installed in such a sensitive environment.
Mr Nathan said the HOBAS pipe was performing very well on the project, and that the pipe has already been planned for another QUU project.
Mr Everard said the Deebing Creek Trunk Sewer Main Project is expected to remain on budget, and is running ahead of schedule for a projected completion in July 2012.
To view images from the microtunnelling display, click here.