Lane Cove Tunnel / Nov 2005 – May, 2006

Client: Alstom / United Group

Supervising Surveyor: Scott Deveridge (Associate Director)

Survey Team: Mathew Hynes / Nathan Milligan

Background:

The lane cove tunnel is a new infrastructure project in Sydney linking the M2 and the Gore Hill Expressway. The project consists of 3.6 km of twin lane tunnel in both an easterly and westerly direction. Total length 7.2 km

United group was engaged by Thiess /John Holland to install lighting, smart signals, all electrical services, All fire services, traffic monitoring camera and the like.

We are engaged by United group to provide survey set out of those services on the tunnel walls and roof area.

Description:

The tunnel was bored by Theiss /John Holland and the road surface had been prepared in each section of tunnel prior to us carrying out works. Information was supplied by the client  detailing the position of the services in relation to the new jersey barrier.

The services set out were;

• Cable trays
• Deluge / Fire sprinkler system
• Fire detection
• Cable Trays
• Cameras and signs
• Lighting
• Electrical cabinets

As each section of the tunnel was opened to United, we were required to place marks for these services in the tunnel roof and side walls. The marks were required to be placed to an accuracy of 5mm or better to ensure that the services were in their correct design position without kinks and to ensure fitment of all services.

In excess of 15 000 marks were placed for the servicing of the tunnel. In addition, various as built surveys and some surface works for the positioning of signs was also undertaken.

The project presented its own challenges in terms of access requirements, OH & S and client liaison with numerous different levels within United Group. It was imperative that we keep ahead of United at all times, and this often meant working smarter and becoming more automated.

All marks were individually tagged, numbered recorded and offsets noted on the tag.

As most marks were placed at an offset to design position and they were to be used almost immediately, reporting back to United was an issue that required immediate resolution. The flow of information back to United exceeded requirements and the marks were able to be used as and when required. Quality assurance and redundancy of measurement ensured errors were all but eliminated.

United were able to maintain their extremely tight program for the duration fo our involvement in the project.

This project allowed us to showcase our skills and maturity as construction set out surveyors. Our flexible approach and commitment  to the project ensured that all went smoothly for United Group and the project did not suffer un due delay due to poor survey methodology or implementation.