October 2016 – Menard Oceania successfully completed the installation of jet grouting columns within a sheet pile culvert and temporary anchors to stabilize the ground for a new busway tunnel in Adelaide CBD, as part of the O’Bahn City Access Project.
Working closely with our customer, McConnell Dowell, we developed a design and construct solution in order to support the existing road and structures at ground level. In total 58 jet grouting columns (ranging from 1.2m to 1.6m diameter) and 36 ground anchors were installed.
4 things make this project unique: complex ground conditions, working near traffic in a confined environment, spoil management and -last but not least- incredibly arduous weather conditions!
Indeed, not only Mother Nature provided a big challenge with complex ground conditions consisting of stiff clays overlaying gravels and dense sand, but also with tough weather conditions: our team had to face abnormal rainfalls during their period of works as well as a cyclone with destructive wind (up to 140km/h!)
Photo: Night works at Hackney Road and Botanic Road Intersection
“Works inside the culvert could only be carried out when the water level inside the culvert was under coffer dam (1m high). This culvert is the catchment of other 16 creeks around Adelaide Hills so the flow can go for 3 -4 days after a rain event. Initially the program was already tight with a very small margin of delay, so you can imagine the rainfalls made it even more challenging in terms of works planning!” said Tin Le, project engineer.
Working near traffic and managing the 70m3 of slurry spoil generated on the road level each shift was not an easy task either, but Menard Oceania team did very well with environmental control and protection to prevent grout splashing to cars and spill on the road. The spoil was removed with vacuum trucks.
Jet grouting works – another night shift in Adelaide for Menard Oceania’s team
The project was successfully completed within 7 weeks and demonstrates the ongoing commitment of Menard Oceania’s crew to work safely and efficiently when handling ground engineering challenges. But not time for rest, our project engineer Tin Le and his team are already heading to Tasmania for the Melrose Dam project where they will be undertaking foundation drilling and grouting works.
Download the entire case study here
ABOUT MENARD GROUP Oceania
Menard Group s a design-build specialty geotechnical contractor offering expertise in ground improvement for sites with poor soil. By combining value engineering and innovative techniques, Menard Group Oceania delivers practical, sustainable solutions that can be attractive alternatives to deep (pile) foundations. As part of an international network of geotechnical resources and expertise, our team brings in-depth knowledge and creative problem solving to every project.