00641445

Component

http://onlinepubs.trb.org...trr/1993/1406/1406-016.pdf

https://scholar.google.co...rson&publication_year=1993

The stress state imposed on subgrade materials during laboratory resilient modulus testing is compared with the anticipated stress state for in situ conditions during traffic loading. Revisions to AASHTO and the Strategic Highway Research Program resilient modulus testing procedures are under way; however, previously most resilient modulus tests have been performed according to the former AASHTO T274-82 specification. In this study, the stress state called for in AASHTO T274 was found to overstress subgrade specimens compared to traffic loading. The issue of stress state needs to be evaluated carefully in making revisions to the testing procedure. The probable effect of overstressing is discussed. Overstressing from shear and normal loading, which have opposite effects on the laboratory-measured resilient modulus, are both considered. Recommendations for resilient modulus testing of subgrade materials are made. The recommended procedure is designed to eliminate overstressing the test specimen. It is also designed to improve the degree to which preconditioning of the specimen removes plastic strains prior to obtaining measurements required for determining the resilient modulus. Laboratory tests on several subgrade materials are conducted using the modified procedure.

This paper appears in Transportation Research Record No. 1406, Construction Robotics and Automation, and Foundations Engineering. 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

01403255

English

p. 124-132

1993

Transportation Research Record

0309055539

Figures (7) ; References (18) ; Tables (2)

Laboratory tests; Modulus of resilience; Recommendations; Subgrade materials; Test procedures

American Association of State Highway and Transportation Officials; Strategic Highway Research Program

Revisions

Geotechnology; Highways; Research; I42: Soil Mechanics

TRIS, TRB, ATRI

Jan 25 1994 12:00AM

• APPLICABILITY OF RESILIENT CONSTITUTIVE MODELS OF GRANULAR MATERIAL FOR UNBOUND BASE LAYERS
• COLORADO'S KNOWLEDGE SYSTEM FOR RETAINING WALL SELECTION
• COSTS AND BENEFITS OF AUTOMATED ROAD MAINTENANCE
• DEFORMATION CHARACTERISTICS OF SUBGRADE SOILS IN KUWAIT
• DISPERSIVE CLAY EMBANKMENT EROSION: A CASE HISTORY
• EFFECTS OF COMPACTOR FOOTPRINTS ON THE RESPONSE OF SUBGRADE SOIL
• EXPERT SYSTEM FOR DRILLED SHAFT CONSTRUCTION
• FIELD AND LABORATORY EVALUATION OF THE MECHANICAL BEHAVIOR OF UNBOUND GRANULAR MATERIALS IN PAVEMENTS
• GEOTECHNICAL CHARACTERISTICS OF SALT-BEARING SOILS IN KUWAIT
• INTERFERENCE EFFECTS BETWEEN TWO SURFACE FOOTINGS ON LAYERED SOIL
• METHODOLOGY FOR RESILIENT MODULUS TESTING OF COHESIONLESS SUBGRADES
• PREDICTED AND OBSERVED BEHAVIOR OF A DEEP-SOIL-MIXING BRACED WALL
• SIMPLIFIED DIRECT CALCULATION OF SUBGRADE MODULUS FROM NONDESTRUCTIVE PAVEMENT DEFLECTION TESTING
• TECHNICAL AND ECONOMIC FEASIBILITY OF AUTOMATED REINFORCEMENT BAR FASTENING ON BRIDGE DECKS
• TOWARD AN ADAPTIVE CONTROL MODEL FOR ROBOTIC BACKHOE EXCAVATION
• VERIFYING KNEADING RESILIENT MODULUS OF SOILS WITH BACKCALCULATED VALUES