Abstract: Methods of design, testing and quality control for asphalt concrete pavement mixtures.

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: The object of the invention is a method for defining elastic deformations and integral angle between of the most important parts of a gyratory compactor, in which method the angle of gyration of a gyratory compactor is measured during the use of the gyratory compactor. The object of the invention is also a device in accordance with the claim 1, which device includes measuring elements (13, 20, 27, 28) for measuring the angle of gyration of a gyratory compactor. Characteristic to the method in accordance with the invention is the fact that a loading device (1) is adjusted in the place of mass specimen, the loading of which on the gyratory compactor is earlier known and that the gyratory compactor will be in use while the loading device (1) is inside the gyratory compactor. Characteristic to the device in accordance with the invention is the fact that the device includes at least one loading device which can be placed inside the specimen cylinder mold of the gyratory compactor.

Abstract: A gyratory compacting apparatus and data capture and display system for compacting a specimen of material within a mold as the mold is gyrated, and capturing and displaying data on an internal angle of gyration during mold gyration, the apparatus and system having a generally cylindrical mold for holding a specimen of material to be compacted, at least one plate in the mold in contact with material in the mold and which moves relative to the mold as the mold is gyrated, and at least one sensor which measures an internal angle of gyration between the mold and a mold plate and captures internal gyration angle data for real-time display of internal gyration angle data during gyration and compaction. Alternative arrays of internal gyration angle sensors are disclosed.

Abstract: A system and method for measuring forces and behavior of a material when subjected to an applied force in a contained vessel or mold in directions not aligned with the applied force. Materials which flow, including mixed materials with an aggregate and a mastic, can be tested within a material vessel or mold by applying a force to the material within the mold and, in addition to measuring resistance of the material to the applied force, resulting forces applied by the material to the mold walls, for example laterally relative to the applied force, are measured and are indicative of flow characteristics and load bearing performance, and shear strength of the material. In a specific testing device, a material testing mold for use with material testing equipment which applies forces to material within the mold, has a mold cavity formed by walls. At least one portion of the wall is configured to deflect or deform in response to material pressure created by a force applied to the material.

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 quick change electrode assembly for immersion in an electrolytic fluid includes an electrode disc frictionally mounted in a TFE fluorocarbon plug disc holder in a sealed interference fit. Part of the disc holder is selectively assembled in and sealed to a PCTFE adaptor. The adaptor is threadedly mounted on the lower end of a spindle. A contact stud is removably secured on the spindle and extends into the plug disc holder. A coil spring is secured at one end to the contact stud and engages the electrode disc at its other end to complete a conductive path therebetween. The electrode disc may selectively be removed by a tool kit from the unassembled disc holder and quickly replaced with a new electrode disc. The disc holder may then be reinstalled on the adaptor, with the coil spring making a reliable electrical connection with the new electrode disc.

Abstract: An electrode, particularly a miniature electrode, having structural integrity and reliable electrical operation results. A thin fluoroplastic liner, preferably, a TFE fluorocarbon liner, seals an electrode disc core to a PCTFE fluoroplastic shroud. By properly machining and assembling the electrode disc core, TFE fluorocarbon liner and PCTFE fluoroplastic shroud, a fluid tight interference seal is obtained to avoid the electrolytic fluid leaking into the electrode to corrode the conductive electrical path. A stainless steel spring extends between the electrode disc core and an electrode contact in the PCTFE fluoroplastic shroud to complete the conductive path through the electrode. The spring has two flat ends which are held in reliable surface contact with the disc core and the electrode contact by the bias of the spring itself. The spring thus provides a reliable electric connection with good conductivity.