• Dynamic Shear Rheometer (DSR) Test System — consisting of test plates, an environmental chamber, an internal DSR thermometer, a loading device, and a data acquisition system. The manufacturer of the device shall provide a certificate certifying that the frequency, deflection angle, and torque are controlled and measured with an accuracy of 1 percent or less in the range of this measurement. • Test Plates – Stainless Steel or aluminum plates with smooth ground surfaces, consisting of 2 plates (upper and lower) 8.00 ± 0.02mm in diameter and two plates (upper and lower) 25.00 ± 0.05mm in diameter. The lower test plate shall have a minimum thickness or raised portion of 1.5 mm to adequately trim the specimen. The plates shall be formed as an integral part of the test fixtures that are used to mount the plates in the DSR. The upper and lower plates shall be concentric with each other. The movable plate shall rotate without any observable horizontal or vertical wobble. This operation must be checked visually or with a dial gauge held in contact with the edge of the moveable plate while it is being rotated. • Environmental Chamber—For controlling the temperature of the test specimen by heating or cooling. The medium for heating and cooling the specimen in the environmental chamber shall not affect asphalt binder properties. The temperature in the chamber may be controlled by the circulation of fluid such as water, conditioned gas such as nitrogen, or by a suitable arrangement of solid-state Peltier elements surrounding the sample. When forced air is used, a suitable drier must be included to prevent condensation of moisture on the plates and fixtures and, if operating below freezing temperatures, the formation of ice. The environmental chamber and the temperature controller shall control the temperature of the test specimen at the test temperature ±0.1°C. The chamber shall completely enclose the top and bottom plates to minimize thermal gradients. Note: A circulating bath unit, separate from the DSR, that pumps the bath fluid through the test chamber may be required if a fluid medium is used. • Temperature Controller—Capable of maintaining and displaying specimen temperatures for the entire range of test temperatures. • Internal DSR Thermometer—A platinum resistance thermometer (PRT) readable to the nearest 0.1°C. The PRT shall be mounted within the environmental chamber as an integral part of the DSR and near the fixed plate. The internal DSR thermometer should be used to control the temperature of the test specimen between the plates and provide a continuous readout of temperature during the mounting, conditioning, and testing of the specimen.
