AASHTO TP 121:2016 Standard Method of Test for Determining the Viscosity of Emulsified Asphalt by a Rotational Paddle Viscometer.
4.1 The viscometer is used to measure the apparent viscosity of emulsified asphalt at 25°C (77°F), 50°C (122°F), or other agreed-upon temperatures.
4.2. A microprocessor circuitry system functioning in tandem with a temperature probe inserted directly in the sample and equipped with internal electronic sensors detects and analyzes the preset temperature. The system shall control the preset temperature to ±0.1°C (0.5°F) of the preset temperature.
4.3. A paddle is immersed in the emulsified asphalt sample and is rotated at 100 rpm. The apparent viscosity of the sample is obtained and read from the electronic display or printer.
This test method is useful to characterize the viscosity of emulsitied asphalt products, as an element to establish uniformity of shipments and sources of supply.
5.2. The viscosity of emulsi fled asphalts characterizes their flow properties and affects their utility at
50°C (122°F) or at other temperatures. For many applications, the sprayability and workability of emulsified asphalt are directly related to the viscosity. The material must have a viscosity low enough to be sprayed yet high enough to not flow from the crown or grade of the road.
5.3. For mixing-grade emulsified asphalts, the viscosity will affect its workability and resulting film thickness on the aggregate.
5.4. This test method is useful to measure the apparent viscosity of emulsified asphalt at a temperature of 25°C (77°F). 50°C (122°F), or another agreed-upon temperature. The preset temperature and rotational speed at 100 rpm allow for an automated and consistent determination of an emulsified asphalt viscosity within a short time.
Note 2 All dimensions are in millimeters (inches).
The rotational paddle viscometer test system consists of a paddle, temperature probe, sample cup, the sample cup cover, a means of controlling the sample temperature to within ±0.1°C (0.5°F), and a readout system to display viscosity.
6.2. The parts of the viscorneter arc shown in Figures 1, 2, and 3.AASHTO TP 121 pdf dwonload.