Abstract:
THE PROBLEM OF TESTING AND EVALUATING ENGINEERING PROPERTIES OF RED TROPICAL SOILS REFERRED TO IN THE LITERATURE AS "LATERITIC SOILS" IS DISCUSSED. BEFORE WORLD WAR II, THESE SOILS HAD BEEN STUDIED ALMOST EXCLUSIVELY FROM THE STANDPOINT OF AGRONOMY. THE WARFARE IN THE TROPICAL REGIONS AND THE EXPANDED WAR PROGRAM IN THE SOUTHERN UNITED STATES, REVEALED THE PECULIAR BEHAVIOR OF CERTAIN RED SOILS EMPLOYED AS SUBSOIL MATERIAL WHICH DIFFERS FROM THAT OF ORDINARY MAINLAND SOILS. RECOGNIZING THAT LATERITIC SOILS BELONG TO THE GROUPS OF SOILS WHOSE ACCURATE EVALUATION IS DIFFICULT, A STUDY WAS UNDERTAKEN TO DETERMINE THE RELATIONSHIP OF PHYSICAL CHARACTERISTICS OF SELECTED REPRESENTATIVE SOILS FROM HAWAII TO THOSE OF SIMILAR ORIGIN AND APPEARANCE IN THE MAINLAND. THE REPORT DESCRIBES THE ORIGIN AND ALTERATIONS OF THE LATERITES, TOUCHES ON THE AVAILABLE DATA PERTAINING TO THE RESEARCH AND ANALYSES OF THE TROPICAL SOILS AND THEIR SUITABILITY AS IDENTIFICATION CRITERIA IN THE EXISTING CLASSIFICATION SYSTEMS. SOME PROPERTIES PECULIAR TO THE HAWAIIAN LATERITIC SOILS AS REVEALED IN LABORATORY TESTS AND CONFIRMED BY THE FIELD EXPERIENCE IN THE PACIFIC AREA ARE DISCUSSED A SIMILAR COMPARISON STUDY WAS PERFORMED ON SOME MAINLAND RED SOILS WHOSE FIELD PERFORMANCE DEPARTS FROM THE PREDICTED BEHAVIOR BASED ON STANDARD LABORATORY ROUTINE TESTS. THE FRIABLE STRUCTURE CHARACTERISTIC OF THE LATERITIC SOILS MAKES THE EFFECT OF REMOLDING A FACTOR OF FOREMOST IMPORTANCE IN THEIR SUBSEQUENT BEHAVIOR. CERTAIN OF THE ROUTINE LABORATORY TESTS HAD TO BE MODIFIED TO ATTAIN AN INITIAL STATE OF SOIL PUTTY PERMITTING SUCCESSFUL PERFORMANCE OF TESTS. THE LENGTH OF TIME OF WETTING AND REMOLDING PROVED TO BE THE DETERMINING FACTOR INFLUENCING THE OBTAINED RESULTS, AND TENTATIVE TEST PROCEDURE IS INDICATED WHICH MAY REMEDY EXISTING DISCREPANCY IN SOIL EVALUATION. /AUTHOR/
Supplemental Notes:
Vol 26, pp 579-593, FIGS, TABS, 9 REF, APP. 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.
