Mammoet has supported Kenny Constructions with the installation of 59 concrete trusses, weighing up to 70 tonnes each, within an underground station cavern for the Cross River Rail project in Brisbane, Australia.
The project’s aim is to alleviate congestion on Brisbane’s metro transport system. For the installation of the concrete trusses, Kenny Constructions faced numerous obstacles including confined and congested project sites as well as a complex construction sequence that required precision and efficiency in order to minimise disruption to the wider site.
Mammoet devised a solution with a custom packing structure positioned on SPMTs, which enabled the transport and installation of up to four trusses simultaneously. To validate the solution, the team assembled the packing structure and transport configuration in its nearby yard to conduct a series of dry runs. After thorough preparation and on-site rehearsals, the actual operations commenced.
The customer’s tower crane lowered the trusses onto the packing structure, before they were delicately manoeuvred through the confined cavern. The hydraulic suspension and electrical multi-steering system of the SPMTs enabled Mammoet to carefully position the trusses on their designated positions.
The operation’s most challenging aspect was the limited clearance. Each of the trusses had a span of 17.6 m, leaving just 100 mm on either side – a little more than the width of a credit card. Yet the first set of trusses, with a combined weight of 193 tonnes, had to travel to the very far end of the station cavern, a distance of 150m – the length of three Olympic sized swimming pools.
In the first phase, 55 trusses, weighing 48.3 tonnes each, were installed, followed by four extra-large trusses weighing 70 tonnes each in the second phase.
