The SG-42 apparatus for uncompacted void content of coarse aggregate utilizes a scaled-up apparatus and procedure similar to that used for evaluation of fine aggregate. Gradation and void content data provide an indication of angularity, sphericity, and surface texture. As concluded by NCAT’s work, test results relate to permanent deformation and fatigue cracking of asphalt. The test has therefore been recommended to evaluate aggregates for hot-mix asphalt pavement.

Aggregate is allowed to free fall from the hopper into a cylindrical measure. Excess heaped aggregate is struck off using the included bar, the mass is measured, and void content is computed.

The hopper, stand, and measure are stainless steel. The apparatus also includes glass plate for calibration of the measure. A locator pin and circle on the bottom plate of the stand assure centering the measure below the hopper. The apparatus measures 10x10x27in (254x254x686mm), WxDxH. SC-181 lightweight fiberglass reinforced plastic pan is 21.2x15.6x6in (538x396x152mm), LxWxH and recommended for containment of particles during testing. The TSA-163 Chute-end Aggregate Handling Pan is useful for weighing and loading of aggregate test material. Est. Ship Wt.: 30lb (14kg).