ABSTRACT

This study constitutes a portion of a research program to determine the suitability of West Virginia sandstones for use as base or subbase road construction.

Seventy-three thin sections were examined with a petrographic microscope to determine important petrographic features. Fifty hand samples were tested for porosity and permeability.

The relationships between petrographic features and physical tests were studied. The physical tests, conducted by the Department of Tests of the West Virginia State Road Commission, included the percent wear by the Los Angeles test, a freeze and thaw test, a repeated load test, a proposed British test, and a compressive strength test.

Several petrographic features are important in determining the behavior of sandstones in the Los Angeles abrasion test. In argillaceous sandstones, the degree of compaction is important, whereas the degree of cementation and pressure solution are the principal factors determining the percent wear of high-silica sandstones. In calcareous and ferruginous sandstones the degree of cementation is important in determining their strength. The degree of compaction, cementation, and pressure solution of sandstones is reflected by the quantity of large interconnected pores.

The results of the other physical tests indicate that high-silica sandstones would be more suitable than argillaceous sandstones for base and subbase course use under flexible pavement. Differences in compaction in the wet and dry state and breakdown caused by freezing and thawing make argillaceous sandstone undesirable.