01046109

Component

A rational, mechanistic constitutive model to predict the permanent deformation of subgrade pavement materials under repeated load triaxial tests was developed. A major advantage of the developed model is that it considers the permanent (plastic) as well as the resilient strain of the material which can be directly calculated from multi-layer elastic pavement response models. The model was developed based on static triaxial shear strength and repeated load triaxial test data conducted on four subgrade materials found in the State of Arizona. These materials included cohesive as well as cohesionless materials with the percentage of fines ranging from 1.2% to 31.5%. The plasticity index of these materials ranged from zero to 17.2%. In order to take into account the expected range of moisture variations in the field, all specimens were initially compacted at the target maximum dry density and optimum moisture content values according to the Standard Proctor method. A portion of these compacted specimens were tested directly after compaction; while, others were either soaked in water or dried out in air and tested after a 24 hour conditioning period, in order for the moisture to reach an equilibrium condition. The developed model accurately predicts the permanent strain, as a function of resilient response, number of stress repetitions, degree of saturation, state of stress, material strength, plasticity index and percentage passing sieve number 200 (% fines).

01042056

07-2318

English

23p

2007

Transportation Research Board 86th Annual Meeting

CD-ROM

Figures (6) ; References (39) ; Tables (6)

Base course (Pavements); Cohesionless materials; Moisture content; Pavement design; Pavement distress; Pavement layers; Pavement performance; Pavements; Subgrade (Pavements); Triaxial shear tests

Pavement response model; Permanent deformation

Arizona

Construction; Design; Geotechnology; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I33: Other Materials used in Pavement Layers; I35: Miscellaneous Materials; I52: Construction of Pavements and Surfacings

Transportation Research Board Annual Meeting 2007 Paper #07-2318

TRIS, TRB

Feb 8 2007 7:00PM