Abstract:
RELATIVELY THIN BITUMINOUS WEARING SURFACES (THICKNESS LESS THAN 2 IN.) SHOULD BE PLACED ON BASES CAPABLE OF SUPPORTING THE WHEEL LOADS USING THE PAVEMENT OVER THE EXISTING SUBGRADE. MOST WEARING SURFACES OF THIS THICKNESS ARE PLACED ON SOCALLED LOW-COST BASES COMPOSED OF SELECTED TOPSOIL AND SAND-CLAY, SOIL-AGGREGATE MIXTURES, OR CRUSHED STONE AND GRAVEL. STABILIZED BASE COURSES, OR BASES CONSISTING OF SOIL MIXED WITH PORTLAND CEMENT, BITUMINOUS MATERIALS, VINSOL RESIN, AND OTHER AGENTS WHICH TEND TO CHANGE THE NATURAL PROPERTIES OF THE SOIL ARE ALSO USED WITH THIN BITUMINOUS WEARING COURSES, BUT THEY ARE NOT CONSIDERED IN THIS PAPER. THIS PAPER DEALS WITH THE THICKNESS DESIGN OF BASES COMPOSED OF UNTREATED, SELECTED SOIL AND CRUSHED STONE OR GRAVEL. THE RATIONAL DETERMINATION OF THE THICKNESS OF SOIL AND AGGREGATE BASE COURSES IS DEPENDENT UPON THREE MAIN FACTORS: (1) THE LOAD AND ITS MODE OF APPLICATION; (2) THE BEARING CAPACITY OF THE MATERIALS USED IN THE BASE STRUCTURE AS WELL AS THAT OF THE SUBGRADE; AND (3) THE DISTRIBUTION OF THE PRESSURE EXERTED BY THE APPLIED LOAD. THE METHODS USED IN DETERMINING THE VALUES FOR LOADS AND BEARING CAPACITY ARE GIVEN IN THIS PAPER TOGETHER WITH THE FORMULA FOR THE CALCULATION OF BASE THICKNESS AS DEVELOPED BY VOKAC. /AUTHOR/
Supplemental Notes:
Vol 26, pp 58-65, 7 TAB, 4 REF. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
