Main West and Main North - Lithgow and Armidale

The Challenge:

The client request we establish  survey control and undertake track design the NSW Main West and Main North railway lines.

The Main West section extended from the end of the Sydney electrified section at Bowenfelds at Lithgow to Wallerawang. It included the survey and assessment of the kinematic envelope of the double-track Marrangaro tunnel at the top of the grade. It also included a kinematic envelope assessment of the overhead highway bridge.

The Main North section extended from Kootingal to Armidale over a 100km distance. Kinematic envelope assessments were required of the Limbri Tunnel and the Woolbrook Bridge. No survey had been undertaken of much of this line since its construction in the 1880s. This line had many tight curves, deep cuttings and short straight sections.

In accordance with their multi-year program, the client intended to re-sleeper all curves with concrete sleepers and replace defective track. The design brief required 80 km/h track speeds and minimal track pulls from the existing alignment.

The Solution:

The tender brief requires the track design be applied to allow trains to operate at an ideal track speed of 80 km/hr but minimises track lateral shifts or “pull”.

The work to be completed includes installation of permanent survey control marks to Map Grid of Australia coordinates, survey of existing rail track, track re-design and placement of track construction marks for tamping crews to "pull" the track to the design geometry.
 

Survey work commenced in Sept 2015 with final project document delivery in June 2016.