Abstract: A gyratory shear material compacting device in which a material sample is placed within a cylindrical mold having a wobble plate. The material sample is compressed by a piston while the mold is simultaneously gyrated. Gyration is achieved by tilting the mold and holding the wobble plate within rollers which revolve around the mold, controlling the selected angle of tilt while imparting oscillatory gyration. The selected angle of tilt of the mold may be precisely controlled at all times, preventing the mold from riding up on the sample, or from coming into contact with the base of the device. The mold is free to advance rotationally. The device is capable of measuring and recording the height of the sample, angle of gyration, and moment of gyration.

Abstract: An automatic compaction assembly for compacting samples of asphaltic or bituminous materials is disclosed. A slide hammer is carried for vertical motion along a guide rod which has a compaction foot at a lower end. A drive chain is driven along a generally triangular path by a suitable drive motor and has weight engaging and raising lugs. An upper chain sprocket shuttle and a lower chain sprocket shuttle are slideably carried in a main frame of the compactor and cooperate with a drive sprocket on the drive motor to define the triangular path of chain travel. A horizontal overarm is formed as a portion of the upper shuttle and receives the upper end of the guide rod. As the guide rod moves downwardly, the release point defined by the upper shuttle also moves down thereby maintaining a constant weight drop distance during sample compaction. The slide weight, after being released from the drive chain continues to move upwardly along the guide rod until its upward travel is halted by gravity.

Abstract: An improved apparatus for mechanically compacting bituminous paving materials is disclosed comprising a compaction foot having a guide rod extending upwardly therefrom. A compaction hammer is slidable on the guide rod and means are provided for elevating the hammer to a position spaced above the foot. Means are provided for releasing the hammer from the elevating means, the releasing means including means for pivoting the guide rod and the hammer away from their normal vertical position to permit the hammer to fall and strike the compaction foot. The means for pivoting the guide rod includes a releaser body pivotally fixed to the guide rod.