Abstract: The moisture susceptibility material testing apparatus includes a specimen chuck, multiple rollers, a temperature controlled water bath, and a control system to automate the testing cycle and collection of data. The water bath is prepared at the desired testing temperature. A material specimen, such as a cylindrical hot mix asphalt (HMA) material specimen, is placed within the water bath on multiple rollers and a specimen chuck then clamps the specimen with an adjustable force. A first and second roller are positioned about the exterior circumference of the cylindrical specimen and a predetermined force is applied radially to the specimen through a third roller. The specimen is rotated about its cylindrical axis, driven by the rotation of the rollers and specimen chuck. A displacement sensor monitors the position of the third roller, yielding a measurement of the rut depth on the material specimen.

Abstract: Devices and methods for providing a known resistance load and measuring an internal gyration angle of a mold in a gyratory compactor. A device in one form has a cylindrical body with protrusions through which a known resistance force is applied by the gyratory compactor, and probes which extend from the body to measure an internal angle of gyration of a mold within a gyratory compactor. The device is placed into a cylindrical mold which is placed into a gyratory compactor. Mold end plates may or may not be required depending on the gyratory compactor configuration and construction of the device body. As the mold is tilted on its axis to an operative gyration angle, the protrusions on each end of the body apply a moment force to the mold which produces a known resistance force on the gyratory compactor frame. Measurement of an internal angle of gyration is made while the resistance force is applied to the compactor frame and while the gyratory compactor gyrates the mold.

Abstract: Devices and methods for providing a known resistance load and measuring an internal gyration angle of a mold in a gyratory compactor. A device in one form has a cylindrical body with protrusions through which a known resistance force is applied by the gyratory compactor, and probes which extend from the body to measure an internal angle of gyration of a mold within a gyratory compactor. The device is placed into a cylindrical mold which is placed into a gyratory compactor. Mold end plates may or may not be required depending on the gyratory compactor configuration and construction of the device body. As the mold is tilted on its axis to an operative gyration angle, the protrusions on each end of the body apply a moment force to the mold which produces a known resistance force on the gyratory compactor frame. Measurement of an internal angle of gyration is made while the resistance force is applied to the compactor frame and while the gyratory compactor gyrates the mold.

Abstract: The moisture susceptibility material testing apparatus includes a specimen chuck, multiple rollers, a temperature controlled water bath, and a control system to automate the testing cycle and collection of data. The water bath is prepared at the desired testing temperature. A material specimen, such as a cylindrical hot mix asphalt (HMA) material specimen, is placed within the water bath on multiple rollers and a specimen chuck then clamps the specimen with an adjustable force. A first and second roller are positioned about the exterior circumference of the cylindrical specimen and a predetermined force is applied radially to the specimen through a third roller. The specimen is rotated about its cylindrical axis, driven by the rotation of the rollers and specimen chuck. A displacement sensor monitors the position of the third roller, yielding a measurement of the rut depth on the material specimen.

Abstract: A portable combined gyratory compactor and extruder for compacting a specimen of material in a mold held in a mold gyration assembly and gyrated about a longitudinal axis as a compaction ram is driven into the mold, and for extruding compacted material from the mold without removing the mold from the mold gyration assembly. The mold gyration assembly is suspended from a spherical bearing pivot positioned lateral to the longitudinal axes of the mold and the compaction ram. The compaction ram is drivingly insertable up into the mold through the bottom of the mold to compact material in the mold as the mold is gyrated by the mold gyration assembly. When the gyratory compaction is completed, a top cap assembly over the top of the mold is removed to allow the compaction ram to be driven farther upward into the mold to extrude compacted material through the open top of the mold while the mold is held in the mold gyration assembly.

Abstract: A gyratory compacting and mold extruding apparatus for compacting a specimen of material within a mold as the mold is gyrated includes a frame for supporting a mold, a mold gyrating carriage, a compaction ram and ram driving assembly, and a mold specimen extruder. The mold gyrating carriage receives a cylindrical mold having a cavity for holding material and an external peripheral flange about which the mold carriage is guided and driven to gyrate the mold while the ram is drivingly inserted through the open top of the mold. The ram driving assembly is supported by a flexible portion of the frame which flexes in reaction to force transferred by the ram. Strain gauges on the flexible portion of the frame provide feedback control data on ram force to an integrated computer control system which selectively controls the ram driving assembly to control the force transferred by the ram at least partially according to data generated by the strain gauges.

Abstract: A gyratory compacting apparatus for compacting a specimen of material subjected to pressure while gyrating the material includes a frame for supporting a mold, a mold gyrating carriage, a ram, and a ram driving assembly. The mold gyrating carriage receives a cylindrical mold having a cavity for holding material and an external peripheral flange about which the mold carriage is guided and driven to rotate to gyrate the mold while the ram is drivingly inserted through the open top of the mold. The ram driving assembly is supported by a flexible portion of the frame which flexes in reaction to force transferred by the ram. Strain gauges on the flexible portion of the frame provide feedback control data on ram force to an integrated computer control system which selectively controls the ram driving assembly to control the force transferred by the ram at least partially according to data generated by the strain gauges. The energy required to rotate the mold gyrating carriage around the mold is measured.

Abstract: A driverless vehicle having swivel-mounted support wheels which ride on track rails and at least first and second drive wheels adapted for frictional contact with a drive tube. The drive wheels are interconnected by a linkage permitting limited independent movement of the drive wheels through a track curve, and they are maintained in substantially synchronous angular orientations relative to the drive tube by means of a stationary cam and a follower mounted on one of the drive wheels or by means of a linkage interconnecting one of the support wheels with one of the drive wheels.