PERFORMANCE EVALUATIONS OF CRUSHED SANDSTONE AGGREGATES IN BITUMINOUS BASES. FINAL REPORT

The principal objective of the research effort was to develop historical performance data for bituminous sandstone pavements and bituminous limestone pavements relative to visual distress, pavement rutting characteristics, and structural condition using deflection measurements. Data relative to Road Rater deflections, pavement rutting, condition ratings based on subjective visual surveys and objective data such as skid resistance and rideability, were collected and analyzed during the course of the study. It was concluded, based upon information gained during the evaluation period and summarized in this report, that pavements constructed with bituminous sandstone bases did not develop excessive rut depths, were more resistant to shoving and pushing, but appeared to exhibit cracking at an earlier age than pavements constructed with bituminous limestone bases. The use of bituminous sandstone mixtures addresses problems such as haul costs, rutting, skid resistance, etc. Field engineers indicated that although bituminous sandstone surface mixtures have a slight tendency to ravel, they are very resistant to rutting and applications of bituminous sandstone base and surface mixtures have been very successful in their estimation.