00238159

Component

http://onlinepubs.trb.org...s/hrr/1973/431/431-003.pdf

THIS PAPER DISCUSSES THE ASSESSMENT OF THE EFFECTS OF FREEZING AND THAWING ON THE STIFFNESS OF SUBGRADE SOILS IN AN ENVIRONMENT REPRESENTATIVE OF THE NORTH CENTRAL PORTION OF THE NORTH AMERICAN CONTINENT. SUBGRADE SAMPLES WERE TAKEN IN THE FALL OF 1970 AND IN THE SPRING OF 1972 FROM A ROAD IN THE PROVINCE OF SASKATCHEWAN. THESE SAMPLES WERE USED TO DETERMINE IN SITU SUCTION AND RESILIENT MODULI VALUES REPRESENTATIVE OF THOSE EXISTING IN THE SPRING AND THE FALL, AND A LABORATORY TEST WAS DEVELOPED TO DUPLICATE THESE CONDITIONS. MODULI OF THE UNDISTURBED SAMPLES OBTAINED DURING THE SPRING WERE CONSIDERABLY LOWER THAN THOSE FOR SAMPLES OBTAINED IN THE FALL, WHEREAS MODULI OF THE REMOLDED SAMPLES WERE CONSIDERABLY HIGHER THAN THOSE OF THE UNDISTURBED SAMPLES, PROBABLY REFLECTING THE PRESENCE OF SECONDARY STRUCTURE IN THE UNDISTURBED SAMPLES. AFTER TWO FREEZE-THAW CYCLES ON THE REMOLDED SAMPLES, MODULI WERE OBTAINED SIMILAR TO THE VALUES OBTAINED FOR THE 1972 SPRING SAMPLES. SUCTION VALUES OBTAINED FOR THE UNDISTURBED SAMPLES WERE LOWER THAN FOR REMOLDED SAMPLES. IN SITU SUCTION VALUES APPEAR TO RANGE BETWEEN 5 AND 30 PSI, INDICATING THE NEED FOR PRECISE TECHNIQUES FOR MEASUREMENT. APPLICABILITY OF THE PSYCHROMETER FOR DETERMINATION OF IN SITU SUCTION VALUES WAS INVESTIGATED; THIS DEVICE DOES NOT APPEAR SUFFICIENTLY ACCURATE TO MEASURE SUCTIONS IN THIS LOW RANGE.

Sponsored by Committee on Strength and Deformation Characteristics of Pavement Sections. 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.

01410347

pp 25-37

1973

Highway Research Record

52nd Annual Meeting of the Highway Research Board

0309021618

Print

Figures (15) ; References (15) ; Tables (1)

Freeze thaw durability; Laboratory tests; Resilience (Materials); Soil suction; Stiffness; Subgrade (Pavements)

Suction

Geotechnology; Highways

TRIS, TRB

Dec 22 1973 12:00AM

• CALCULATION OF THE ELASTIC MODULI OF A TWO-LAYER PAVEMENT SYSTEM FROM MEASURED SURFACE DEFLECTIONS
• DETERMINATION OF YOUNG'S MODULUS FOR BITUMINOUS MATERIALS IN PAVEMENT DESIGN
• GRAPHICAL TECHNIQUE FOR DETERMINING THE ELASTIC MODULI OF A TWO-LAYER STRUCTURE FROM MEASURED SURFACE DEFLECTIONS (ABRIDGMENT)
• PERMEABILITY COEFFICIENT USING A NEW PLASTIC DEVICE
• STRUCTURAL DESIGN PROCEDURE FOR STABILIZED PAVEMENT LAYERS