Jet Grouting For Lisarow Rail Bridge Renewal

This paper describes the design and installation of a jet grouted deep foundation system to support a rail bridge on the Main North Line, just north of Lisarow in New South Wales, as part of a bridge renewal. The adopted method of jet grouting is a replacement/mixing technology that uses a high pressure jet to erode and hydraulically excavate soils, to form a grouted soil mass. This is understood to be the first application of the jet grouting technique to support a rail bridge in Australia.

Parsons Brinckerhoff provided a specification, reference design, construction surveillance and certification for the works. Following consideration of alternatives, including driven piles, compaction grouting and mini-piles, Austress Menard was selected to construct the works on a design and construct basis, using jet grouting.

The project was completed on schedule, during limited track possession time, under low headroom conditions. The specification requirements, design, installation, monitoring and post-construction performance of the successful footing system are outlined in this paper.