This main was laid in reclaimed landfill about 10 years ago and in recent years has failed on numerous occasions and had been repaired using internal patch repair and external gibault joiners. Previous repairs of the pipe had proven to be unsuccessful, and so the possibility of using the pipe bursting method was explored by the airport authority. Pipe bursting provided a solution that would install a new pipe under the road while maintaining airport operations.

Ipswich Water was awarded the tender to replace the rising sewer main by the pipe bursting technique and used a Grundoburst 800G Hydraulic Pipe Burster recently purchased by Tyco Water from TT Asia Pacific Pty Ltd. The project involved the installation of 65 metres of 355 mm HDPE pipe. The Grundoburst machine, built in Germany by Tracto-Technik was chosen for its compactness and yet very high strength – 80 tonne pull back, which was ideal for this project. The QuickLock rods, a notable feature of the Grundoburst machine, made for easy connection and disconnection, even in difficult conditions.

Difficulties were encountered with de-watering and sand control in the pits, while setting up and working the pipe bursting machine at the pipe depth of 2.8 metres. When pulling the expander and replacement pipe, the tri-blade burst head cut through the old PVC pipe and internal repairs were conducted while the expander squeezed out the old pipe fragments into the surrounding ground. The gibault repair joiners collected in front of the expander and ended up back at the machine when completed. The first 55 metres took 40 minutes to complete.

The project was completed within the scheduled time frame with the new pipe installed and connected.

Ipswich Water have been using a Grundoburst 400G (40 tonne) machine for the last two and a half years and were very impressed with the 800G machine, which is not much bigger than their 40 tonne machine, yet is twice as powerful. Ipswich Water have now decided to add the Grundoburst 800G to their fleet of equipment for pipe rehabilitation work.

TT Asia Pacific had been involved from the beginning of this project assisting with machine and tooling selection through to providing some of the special accessories and finally with on-site support during the pipe bursting process.

The satisfaction that comes from completing another successful Trenchless Technology project is boosted by the knowledge that no disruption to airport activities or the terminals’ busy vehicular and pedestrian traffic flow occurred during the project.

Currently, there are Grundoburst 40 tonne machines working in Queensland, New South Wales, and Victoria. Grundoburst 400G Pipe Bursting machines have entered the busy Hong Kong region and are working on large refurbishment programs. Grundoburst 800G (80 tonne) machines are already working and producing successful results in the Asia Pacific Region in China, New Zealand and Australia with the delivery of a Grundoburst 1000G (100 tonne-pullback) unit to Beijing.

For further details on this or other Trenchless Technology equipment contact Peter or Tom at TT Asia Pacific on 07 55614999, fax 0755614900 or email info@tt-asiapacific.com.