Marshall Compactors compact hot mix asphalt test specimens for Marshall stability and flow testing, density/void determinations, and specific gravity. Compactors are available in manual or automatic models. Specimen diameter is determined by the maximum aggregate size. 4in (102mm) diameter specimens are suitable for mixes containing aggregates up to 1in (25.4mm), and 6in (152mm) diameter specimens are used for aggregate sizes up to 1-1/2in (38.1mm).
Click the Marshall Compactor Comparison Table above to enlarge, print, or download. The table compares operation, base rotation, blow-counter option, number of hammers, and mold size.
Gilson’s manual Marshall compactor implements a hand-operated drop hammer on a guide rod to compact asphalt samples and is suitable for periodic use. The manual compactor utilizes a stationary mold and a flat-faced hammer to evenly compact the asphalt specimen.
The automatic Marshall compactors use an electric motor to automatically raise the drop-hammer between successive blows and feature a hammer-blow counter that turns off the unit at the completion of compaction, significantly decreasing operator intervention. Automatic compactors are available with a stationary mold and flat-faced hammer or rotating-base mold models with a tapered-foot hammer. Automatic, rotating-base models ensure uniform compaction over the entire specimen for more precise testing results. Automatic models are also available in single, double, or triple mold/hammer configurations for increased throughput for high-volume testing labs.