SITECH® UK & Ireland have supplied Trimble® technology to specialist earthworks contractor RJT Excavations delivering huge cost savings on the Carlisle Southern Link Road (CSLR) project in Cumbria.

With the help of SITECH, authorised dealer of Trimble® Civil Construction Field Systems, Scottish Borders-based RJT deployed a Trimble® Universal Total Station (UTS) high-precision positioning system for the first time. This innovative technology delivers millimetre-level machine guidance, reducing both the amount of surfacing materials used on the 8km stretch of road, and the time taken for surveys and rechecking.

Gary Garner, Engineering Manager at RJT describes how the company came to use the UTS system: “Having worked on many civil engineering projects where accuracy is important, we are used to working with Trimble GPS and real-time kinetic corrections. For this project we knew that even greater accuracy would pay dividends. Having worked closely with SITECH for over 10 years we asked about UTS. They supplied the kit and gave us all the technical support we needed to set up the system and get the best out of it throughout the project.”

The GPS used in standard machine guidance compares time signals from multiple satellites to fix a machine’s position to within a few centimetres. UTS relies instead on a ‘total station’ in a fixed position on the ground, which uses line of sight lasers which bounce off reflectors mounted on the equipment. Data from the station integrates with the Trimble Earthworks 3D machine control system to guide machines to within a couple of millimetres.

Garner explains how the system is delivering significant savings on the project: “As long as the total station has line of sight it can stay in position for a whole day so just needs setting up once. This enables grading of the road surface to millimetre-level precision with no interruptions for manual stakeouts or rechecking.

“This saves time and enables the project to proceed with fewer surveying personnel, thereby minimising the interaction between plant machinery and operatives. Reducing the manual aspect of the project also delivers health and safety benefits as operatives don’t need to work alongside the plant, significantly reducing the risk of injury on site.

“It also allows for a perfect spread of tarmac first time. While the difference between a few centimetres and a few millimetres might not sound like much, the CSLR is 8km long so overall this method delivered significant cost savings when compared to conventional level control methods.”

Liam Payne, Regional Sales Representative at SITECH, oversaw the supply of the equipment: “RJT hired the equipment first and placed an order to buy very shortly afterwards. This is testament to the overall value of UTS and we expect to see this technology become more commonplace on UK projects going forward.”

The CSLR project is ongoing and scheduled for completion later this year.