Location:
Brisbane, QLD

Client:
SEQ Trenchless

Rig Size:
Midi

Pipe Specs:
2 x 3 140mm HDPE

Max Length:
46m 

Max Depth:
5m

Geology:
Alluvial & Rock

HDD Crossing:
Rail

Pipe Application:
Electrical

FPS provided extensive design and engineering products for these parallel-bore electrical crossings, delivered as part of the Cross River Rail project. With two HDD bores required to be constructed under a rail corridor in hard Brisbane tuff geology, as well as major limitations on space due to the inner-city location, the project posed significant challenges.

FPS provided the HDD contractor, SEQ Trenchless, with engineering documentation to assist them with planning and execution of the difficult works.  This suite included FPS’ standard design pack of profile and alignment, hydrofracture analysis, installation and integrity calculation, and drilling fluid plan, but due to the additional hazards of the rail infrastructure, was also supported by grouting plan, vibration analysis and settlement analysis.  Rod-by-rod drill plan and drilling fluid management plans also supported the contractor’s construction planning efforts.

Installation by SEQ Trenchless commenced in June 2021, but obstacles arose due to unrelated construction works in the area, resulting in changes to surface level. FPS assisted by attending site for updated survey, completing immediate updates to drill plans in order to assist with walkover steering guidance, and providing engineering guidance and support during pilot hole drilling. Despite the changes required, the electrical conduit crossings, situated between the edge of the rail corridor and neighbouring RNA Showgrounds and Old Museum precincts, were successfully completed by the end of the month.