Arrow Road Goes Stringless!

On many projects grade control is critical. Traditionally, in tight grade control circumstances Line and Grade were controlled by a stringline.  Arrow Road now has incorporated Trimble 3D Paving Control systems into our paving fleet. The systems allow us to lay precision asphalt where there isn’t an accurate reference surface and where a stringline would normally be required.

Stringless asphalt paving offers the benefit of eliminating the costly step of bringing in a crew to set up the stringline. Eliminating that step also removes the physical obstacles of the string and pins that get in the way of the paving crews and the workers running ancillary equipment.

Arrows Roads Trimble 3D paving system utilizes the Trimble SPS930 Universal Total Station and onboard software to compare screed positions and slopes with a 3D digital design of the job. The system automatically guides the screed to lay a precise amount of material to achieve the specified thickness and slope.

Arrow’s Trimble SPS930 Universal Total Station, MT900 active target and a Trimble CB460 Control Box gives us flexibility in both 2D+3D control systems. One side of the screed can be 3D height controlled, while the other can be controlled by the variable slope of the 3D design, by a fixed slope or by a surface reference sensor. The Trimble PCS900 system leverages the Trimble SPS930 Universal Total Station, MT900 Machine Target and on-board software to compare the actual screed position and slope with the 3D digital design automatically guiding the screed to lay exactly the right material thickness and slope.

The use of 3D paving control enables Arrow Road to more precisely:

• Control elevations and the amount of asphalt being placed
• Take out high and low areas early in the process with the less expensive first layer materials
• Increase road smoothness while using less asphalt than with traditional paving methods
• Lay complex designs such as transitions, super-elevated curves and frequently changing cross slopes
• Achieve accuracy and smoothness specifications
• Eliminate the time consuming and costly step of setting out stringline

This is just one of the ways Arrow Road is investing to provide higher quality and more economical pavements.