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Title: Moisture-Sensitive and Stress-Dependent Behavior of Unbound Pavement Materials from In Situ Falling Weight Deflectometer Tests
Accession Number: 01475420
Record Type: Component
Record URL: Availability: Transportation Research Board Business Office 500 Fifth Street, NW Find a library where document is available Abstract: In an instrumented flexible pavement with a subsurface drainage system, a field study was performed to investigate the influence of water on the response of the pavement structure. The drainage system of the structure was clogged for 3 months; this condition allowed the groundwater to rise and the structure to undergo high moisture conditions. Reopening of the drainage system permitted the structure to approach its previous draining hydrological state. Along with monitoring of subsurface groundwater level and moisture content, the structural response of the pavement was studied by conducting frequent falling weight deflectometer tests with multilevel loads. The stress sensitivity of the unbound layers and the influence of moisture on their stiffness were studied, with the intent of using the data to determine the unbound materials’ nonlinear parameters through a backcalculation algorithm. The groundwater level rose rapidly after the drainage system was clogged. This rise in groundwater level significantly affected the overall stiffness of the pavement structure, and the backcalculated stiffness of the unbound layers decreased as their moisture content increased. Furthermore, the unbound layers exhibited stress-dependent behavior to multilevel loads. The subgrade showed a stress-softening response in an unsaturated condition and stress-independent behavior in a saturated state. The granular layer exhibited stress-hardening behavior. Backcalculation of the unbound nonlinear parameters determined by the universal extended k–θ model revealed that the k1 parameter decreased with increasing moisture content for both the unbound granular layer and the unsaturated fine-grained subgrade material.
Monograph Title: Monograph Accession #: 01490600
Report/Paper Numbers: 13-1936
Language: English
Authors: Salour, FarhadErlingsson, SigurdurPagination: pp 121–129
Publication Date: 2013
ISBN: 9780309263320
Media Type: Print
Features: Figures
(8)
; Maps; Photos; References
(16)
; Tables
(1)
TRT Terms: Subject Areas: Geotechnology; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways
Files: PRP, TRIS, TRB, ATRI
Created Date: Feb 5 2013 12:27PM
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