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French Plate Rutting Tester for Bituminous Asphalt Testing This compactor is used to accurately test certain characteristics of asphalt by means of a constant pressure applied by a tire. The compacting is carried out by an alternating linear driven, constant speed tandem tire roller at the upper surface of the mold. One or two pneumatic tires may be used. The applied pressure is adjustable. The loose material is held in a container, located beneath the mold. The bottom is raised by an electric driven elevator table, keeping the material level with the uppermost surface of the mold throughout the compacting process; the verification of this level is done visually, while the actual thickness of the slab is constantly displayed. When one tire is used, the slab size is 500mm x 180 mm with thickness of 50 - 150 mm. When both tires are used the slab has a size of 600 x 400 x 50 - 150 mm thick. The chamber of the compactor that holds the loose mixture is deeper than required thickness of the slab at the start of the compaction process. This is necessary in order to accommodate the larger volume of loose mixture. The bottom plate of the mold is free to move up and down. A hydraulic jack is used to push this plate upward during compaction to obtain the required slab thickness. Thickness is monitored automatically. At the end of the process, the slab should be level with the top of the steel mold. The density of the mixture at the required air-void level and the dimensions of the slab are used to calculate the mass of mixture needed. Various sequences of different downward vertical forces, tire pressures, and positions of the tire(s) relative to the width of a slab are used to compact a slab. These parameters depend on the thickness of the slab and the required air-void level.. Standard high and low compaction procedures that supposedly offer these two levels are provided with the machine. Additional slabs are sometimes compacted to an intermediate air-void level to provide a third data point. The vertical force and tire pressure used in the process are initially low to prevent the loose mixture from spilling out of the mold. Both are increased after several passes of the tire. A board or steel plate is placed on top of the slab after the mixture has been compacted. Several passes of the tire are then applied. This helps to level the surface; however, mixtures with maximum aggregate sizes larger than 20 mm may still have a rough surface after compaction. It takes 20 to 25 min to compact a slab. The tubular frames shown in the photos are the safety rails that mount around the machine. Also shown in the photos below are the extra molds and a few spare parts. This unit performs similar tests as Hamburg Wheel Tracking Devices or Georgia Loaded Wheel Testers. Each type has different wheels and different sample preparations. This unit is in good condition and appears to be 1992 vintage. Manual included. Please call with any questions. * Manufacturer: MAP (French company) , now Vectra * Operating Specs: (all are SI units, use convert-me.com to convert to english) * Output Torque: 35.8 m da M * Total travel: 893.68 mm (35.2 in) * Speed 250 mm/s (9.8 in/s) * Lever (uses hydraulic cylinder to apply downward force): * max vertical force: 1040 da N * Transversal positioning movement speed: 94 mm/sec * Max position from the center: +/-119 mm * Electric elevator table system * Verital displacement: 225 mm (8.9 in) * 600 mm x 400 mm x 150 mm (23 5/8" x 15.75" x 6") |