Accession Number : AD0762364

Title :   Shear Strength of Tropical Soils in Relation to Composition and Environment.

Descriptive Note : Final rept. 1970-1972,

Corporate Author : IOWA STATE UNIV AMES ENGINEERING RESEARCH INST

Personal Author(s) : Lohnes,Robert A. ; Demirel,Turgut ; Fish,Russell O. ; Kellogg,C. Gary

Report Date : MAY 1973

Pagination or Media Count : 83

Abstract : Ten soils from Puerto Rico representing various states of weathering were subjected to engineering index tests, strength and density measurements, and mineralogic studies. Standard classification systems used for temperate soils tend to underestimate the engineering behavior of the undisturbed lateritic soils. In general, the undisturbed lateritic soils exhibit low densities and high strengths. At high normal stresses the shear-stresses the shear-stress deformation curves are similar in shape to normally consolidated clays, whereas at lower normal stresses they are shaped like the curves from overconsolidated clays. The normal pressure at which the transition occurs is the collapse pressure and tends to be higher in the more severely weathered soils. This suggests more rigid structure due to greater cementation. The varying degree of cementation can be observed with the scanning electron microscope. (Modified author abstract)

Descriptors :   (*SOIL MECHANICS, *TROPICAL REGIONS), SHEAR STRESSES, TEST METHODS, FLEXURAL STRENGTH, DENSITY, MINERALS, AGING(MATERIALS), EROSION, CLIMATE, CREEP, STRUCTURAL PROPERTIES, CLAY, PUERTO RICO

Subject Categories : Soil Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE