This four-track GP-4000 is equipped with the IDBI system, and on this project, the GOMACO operating system technology allows the machine to be controlled by a stringless 3-D machine-control system. This is a two-layer mainline paving project in the Czech Republic. Paving widths on this project range from 35 ft. (10.7 m) to 40 ft. (12.2 m). The total thickness of the two-layer slab is 12 in. (305 mm).
Two layers of concrete are visible during the demonstration of the two-lift slipforming process. One layer is fed through the hopper, and the other is placed in front of the machine. This test was conducted on the GHP-2800 four-track slipform paver.