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Ajax Paving Goes Completely Stringless Paving with Trimble Paving Control System on Concrete Pavers

Ajax Paving Goes Completely Stringless Paving with Trimble Paving Control System on Concrete Pavers

Ajax Paving Goes Completely Stringless Paving with Trimble Paving Control System on Concrete Pavers
Precise paver control, better material yield, minimal material wasted and early project completion with Trimble PCS900 (3D) paving


Customer Profile 

Founded in Detroit in 1951, Ajax Paving provides industry-leading professional concrete and asphalt paving services completing multi-million dollar contracts in Michigan, Indiana, Ohio, and Florida.

Business Challenge 

In 2013, Ajax was hired to complete a 7,000-foot (2,134 meter) runway project for the Detroit Metro airport. Looking to automate its jobsite, Ajax Paving BETA tested the Trimble Paving Control System, including setting up the solution on one trimmer and two asphalt pavers. After meeting extremely tight tolerances, Ajax invested in its concrete paving fleet and the Trimble Paving Control system.


The team adopted the Trimble® Paving Control System, including PCS900 (3D), PCS400, Trimble Business Center - HCE and the Trimble SPS930 Universal Total Station for its concrete pavers


  • Paved 7,000-foot (2,134 meter) Detroit Metro airport to within 1 millimeter tolerance using zero stringlines
  • Completed the first totally stringless road reconstruction and paving work on a 7-mile stretch of I-96 in Michigan in less than 24 weeks, a full 17 days ahead of schedule
  • In just 167 days, Ajax placed 850,000 tons of aggregate base and poured 85,000 lineal feet (25,908 lineal meters) of material
  • Produced 253 truckloads of material per day at portable batch sites and paved continuously for four months; no lost days and nominal delays in 100,000 person hours of paving work
  • Earned bonus for completing concrete paving of I-96 early and runway project early

Already established as one of the premier asphalt pavers in the country, Ajax Paving has made a significant investment in its concrete paving division over the past 10 years. Based out of its main office in Troy, Michigan, the concrete division of Ajax Paving has since placed more than 14 million square yards (12.8 million square meters) of concrete pavement on over 60 separate airport and highway concrete paving projects.

In the spring of 2013 the company was hired for a runway paving project for the Detroit Metropolitan Wayne County Airport. The project totaled $200 million and required paving a 7,000-foot (2,134 meter) runway. Jeff Robinson, automation manager at Ajax Paving, explains that his team adopted the Trimble Paving Control System, including setting up the solution on one trimmer and two asphalt pavers.

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. It automatically guides the screed to lay exactly the right material thickness and slope.

“With help from Trimble support we were up and running quickly and on day one, we were stringless on the runway project,” said Robinson. “We're able to trim the grade in remarkable tolerance; the surveyors didn't even believe it, but most of the job was within one millimeter tolerance on concrete.”

Robinson recalls that on a highway project in northern Michigan, the paving system allowed his team to continuously pave, even in dense fog, and even when competitors had to stop working due to the weather conditions. The system uses active tracking technology to guarantee the total station locks on the on-machine target for millimeter-level control. Using active tracking, the team was able to keep the machine moving through the dense fog, as opposed to shutting down and wasting 200 feet (61 meters) of concrete already dumped in front of the paver.

Happy with the results from the Metro runway, Ajax invested in the Trimble Paving Control System for its concrete pavers. The team upgraded its eight concrete pavers with the Trimble system, three trimmers, and added two additional asphalt pavers.

With Trimble’s Paving Control System, Ajax has since completed work on a major reconstruction project for the Michigan Department of Transportation (MDOT).  Beginning in April 2014, the reconstruction project consisted of a 7-mile (11 kilometer) stretch of I-96 from Newburgh Road in the city of Livonia to Telegraph Road in Redford Township. The whole project scope was 56 lane miles (90 kilometers), 22 ramps, 37 bridges, 74 approaches on the bridges and 10 retaining walls. One of several contractors, Ajax’s scope of work included 270,000 cubic yards (810,000 cubic feet) of concrete paving. On any given day, approximately 75 to 100 Ajax management and field crew members were on site

Using Trimble Business Center-HCE, Robinson created 3D models for I-96. He converted digital CAD cross-sections and PDF files to develop the accurate, integrated 3D models. He also used Trimble Business Center - HCE to manage data flow between the office, Trimble SCS900 Site Controller Software and Trimble machine control technology.

“I used Trimble Business Center - HCE to build all of the models and keep track of my data going back and forth between machines and data collectors,” said Robinson. “We had two of our batch plants set up on the job that produced 253 truckloads of material per day, which is more than 100,000 man hours in total.”

The PCS900 Paving Control System on concrete pavers is an automatic 3D control system that gives paver operators better control. The system leverages Trimble total stations, on-machine positioning sensors and office software to pave an accurate concrete road while eliminating the need for stringlines.

The Ajax team loaded the 3D road design created in Business Center - HCE onto the machine control box. Then, the PCS900 used automatic steering and grade control to keep the slipform paver on design. Robinson points out that because zero stringlines are needed, concrete paving operations can start sooner and the crew can work continuously. An accurate 3D design model and precise control of the paver minimizes material wasted, and the team can also perform fine grading work more quickly and with greater accuracy. 

“It was well planned and executed because very rarely do we have a job that we are able to pave every day − and we did that for almost four months,” said Robinson. “We paved every single day finishing the job in just 167 days—a full 17 days ahead of schedule.” Robinson credits Trimble Paving Control for the significant time savings. For a project of this scope, in the past Ajax would have to pound in stakes and run line approximately every 25 feet (7.6 meters) to check grade. Using the Trimble systems on the I-96 project, dirt contractors can cut to grade in the morning, place stone on the grade, and by that afternoon Ajax can trim the fine grade. The following day, Ajax can then place the concrete on the stone. “If it wasn't for the Trimble Paving Control System and going stringless, this job would likely have needed 12 full-time stringline setters just to set up for trimming,” said Robinson. “Now, many of those guys can do other high-value things. It was a challenge at first, but it didn’t take long for management to come around; they now no doubt see the benefits.”