00715546

Component

http://onlinepubs.trb.org...trr/1995/1504/1504-009.pdf

https://scholar.google.co...illi&publication_year=1995

The subgrade of road bed soils is generally constructed near the optimum moisture content-dry density combination standard Proctor tests. However, environmental and seasonal variations alter the design moisture contents and the resilient properties of subgrade soils. These changes influence structural performance of pavements. Recent pavement design guides, which use the resilient modulus for characterizing pavement materials, require additional information on seasonal moisture content variations and their influence on resilient properties. This report presents results from an experimental study which investigated the influence of moisture content variations on the resilient modulus of soils. Two soil types, sand and silty clay compacted at above, and below optimum moisture content levels, were tested using the AASHTO T-294 procedure. Two in-cell displacement measurement systems measured displacements with respect to the ends of the specimen and the middle one-third of the specimen. Results indicated that the influence of moisture content on moduli appears to be more evident in clays than in sands. The effect of moisture content on the resilient modulus computed from both measurement systems is discussed. The measurement coefficients used to convert end system moduli to middle system moduli are provided for various moisture content levels in both soils. The influence of conditioning confining stresses and moisture contents on accumulated plastic deformations is also evaluated. The regression model results for the tests conducted in the investigation are also included.

This paper appears in Transportation Research Record No. 1504, Modeling and Model Verification; Testing Pavement Layers and Materials; and Low-Cost Drainage Structures. 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

01399829

English

p. 87-102

1995

Transportation Research Record

0309061725

Figures (7) ; References (11) ; Tables (4)

Compacted soils; Dislocation (Geology); Measurement; Modulus of resilience; Moisture content; Plastic deformation; Regression analysis; Sand; Silty clays; Subgrade (Pavements); Variables

Data and Information Technology; Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB

Jan 2 1996 12:00AM

• CENTRIFUGAL MODELING OF LEAKING UNDERGROUND STORAGE TANKS
• DETERMINATION OF DEPTH TO BEDROCK FROM FALLING WEIGHT DEFLECTOMETER TEST DATA
• DETERMINATION OF RESILIENT MODULUS OF SUBGRADES USING BENDER ELEMENTS
• ESTIMATING PERMEABILITY OF ASPHALT-TREATED BASES
• METHODOLOGY FOR FUNCTIONAL DESIGN OF LOW-LEVEL RIVER CROSSINGS IN SOUTH AFRICA
• MODELING FLOWSLIDES CAUSED BY STATIC LOADING
• MODELING THE STABILITY OF SAND FOUNDATIONS DURING EARTHQUAKES
• PORTABLE CROSSINGS FOR WEAK SOIL AREAS AND STREAMS
• RESPONSE OF PAVEMENT SYSTEMS TO DYNAMIC LOADS IMPOSED BY NONDESTRUCTIVE TESTS
• SHEETPILE CELL FILLING: FINITE ELEMENT MODEL VERIFICATION FOR TWO CASE HISTORIES
• TESTING AND MODELING OF TWO ROCKFALL BARRIERS