Granular Base Materials for Flexible Pavements, HR-131, 1970

The coefficients of relative strength (CORS) of base courses for use in the American association state highway officials (AASHO) interim guide for the design of flexible pavements are determined here. Based on (1) volumetric strain--axial strain relationships at minimum volume, and (2) effective stress ratio-cohesion relationships at maximum effective stress ratio, CORS were determined from the results of laboratory triaxial tests on both asphalt-treated and untreated aggregate base course materials. The researchers conclude that volumetric strain-axial strain at minimum volume appear to be appropriate parameters for determining CORS.

Preliminary Studies of Remedial Measures for the Prevention of Bridge Deck Deterioration, HR-146, 1970

Four series of five specimens each were investigated for static and fatigue strength. These four series differed in that there were two variables, the first being the subsidence of concrete around reinforcing bars and the second being shrinkage due to two different curing conditions. The combinations of these variables were then compared to each other by use of, load-deflection curves and S-H fatigue curves.