00965578

Component

https://doi.org/10.3141/1837-06

http://scholar.google.com...ewis&publication_year=2003

Unbound aggregate base layers in a quarry haul road in Georgia were characterized using embedded sensors and in situ seismic testing. Two sections of the road were constructed as inverted pavements, one using a South African Roads Board method and the other using a conventional Georgia Department of Transportation method. A third was constructed using a traditional method. Miniaturized versions of traditional cross-hole and downhole seismic tests were conducted to determine the stiffnesses of each base layer. Horizontally propagating compression and shear waves were measured under four different loading conditions to determine Young's moduli and Poisson's ratios of the base. An increase in stiffness with an increase in load was measured. Additionally, it was found that the Georgia and South Africa sections had similar stiffnesses. Surprisingly, the traditional section was found to be somewhat stiffer than the other sections. This higher stiffness is thought to be caused by a prolonged period of compaction before construction of the unbound aggregate base layer, which essentially transforms the traditional section into an inverted pavement. Using the vertical total normal stresses computed from ILLI-PAVE, a value of 0.3 for the earth pressure coefficient was found to be reasonable for this material in determining the radial total normal stresses. The radial effective normal stresses were calculated from the radial total normal stresses and experimentally determined pore water pressures. Additionally, the negative pore water pressures in the partially saturated granular base had a significant impact on the stiffness of the unbound aggregate base layer, especially under small load levels.

This paper appears in Transportation Research Record No. 1837, Geomaterials 2003.

English

p. 50-60

2003

Transportation Research Record

030908573X

Figures (10) ; References (6) ; Tables (4)

Aggregates; Base course (Pavements); Coefficients; Earth pressure; Field studies; Flexible pavements; Haul roads; Poisson ratio; Pore water pressures; Stiffness tests; Stresses; Young's modulus

Unbound aggregate base layers

Georgia

Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB, ATRI

Nov 19 2003 12:00AM

• DESIGN OF GRANULAR PAVEMENT LAYERS CONSIDERING CLIMATIC CONDITIONS
• ENGINEERING BEHAVIOR OF STABILIZED SOILS
• ESTIMATION OF THE COMPRESSIVE STRENGTH AND MODULUS OF ELASTICITY OF CEMENT-TREATED AGGREGATE BASE MATERIALS
• MEASURING SULFATE IN SUBGRADE SOIL: DIFFICULTIES AND TRIUMPHS
• MICRO-DEVAL TESTING OF AGGREGATES IN THE SOUTHEAST
• REFINEMENT AND VALIDATION OF THE HYDRAULIC FRACTURE TEST
• STABILIZATION OF SULFATE-CONTAINING SOIL BY CEMENTITIOUS MIXTURES MECHANICAL PROPERTIES
• VALIDATED MODEL FOR PREDICTING FIELD PERFORMANCE OF AGGREGATE BASE COURSES