Diabase aggregate

A traprock (diabase) aggregate used in Northern Virginia for road construction and having a past history of satisfactory service in asphaltic mixtures was chosen for study. 

Optimum Marshall Binder Contents Sulphlex-233 and AC-20 Asphalt Cement With a Well-Graded Diabase Aggregate... 

No precise correlation is available between the immersion-compression test and results to be expected from pavements in the field. The test provides comparative guidance on water damage susceptibility. For the diabase aggregate, the Sulphlex-233 mixtures measured dry, and after immersign in the case of wet specimens, exceed the 300 psi (2.07 x 10 pascal) minimum compressive strength usually considered necessary for acceptable mixture performance in the field. Retained strengths generally fall below the 70 percent criterion considered acceptable for asphaltic mixtures. 

The limestone, the crushed gravel and the diabase aggregates gave methylene blue values below the limiting values regardless of fraction size tested. 

Figure 15.21 shows the effect of using two different aggregates diabase (shrinking aggregate) at the top and limestone (non-shrinking aggregate) at the bottom. 

Basalt and diabase (crushed) Concrete aggregate, railroad ballast, and roofing granules. 

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