00799052

Component

https://doi.org/10.3141/1709-14

http://scholar.google.com...ston&publication_year=2000

Increased water content of subgrade soils can lead to degradation of their quality and result in pavement distress. Pavement performance depends on the modulus of the compacted unsaturated subgrade soil as well as that of the underlying natural soil deposits. The soil modulus is a strong function of water content; therefore, changes in water content over the life of the pavement must be understood. In this study, it has been found that for a relatively near-surface groundwater table, significant potential exists for capillary rise into subgrade soils. For fine-grained soils in particular, the height of this capillary rise can be quite substantial. Results from capillary rise column experiments have shown that soils wetted above the groundwater table through capillary rise remain at a degree of saturation averaging about 60%. It has also been found that soil suction within this capillary zone must be determined through the use of soil water characteristic curves or direct measurement. The conventional assumption that negative pore water pressures can be estimated by backward extrapolation above the groundwater table of a line of slope gamma sub w is only appropriate in a very thin region above the groundwater table, where soils are wetted to a degree of saturation of 85% or more.

This paper appears in Transportation Research Record No. 1709, Geotechnical Aspects of Pavements 2000.

English

p. 114-120

2000

Transportation Research Record

0309066883

Figures (3) ; References (14) ; Tables (1)

Capillary water; Groundwater; Modulus of resilience; Moisture content; Percent saturation; Pore water pressures; Soil suction; Subgrade (Pavements)

Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB, ATRI

Sep 29 2000 12:00AM

• ASSESSMENT OF FALLING WEIGHT DEFLECTOMETER DATA FOR STABILIZED FLEXIBLE PAVEMENTS
• CONSIDERATIONS FOR PROVIDING SUBSURFACE DRAINAGE IN JOINTED CONCRETE PAVEMENTS
• DRAINAGE OF PAVEMENT BASE MATERIAL: DESIGN AND CONSTRUCTION ISSUES
• EFFECTIVENESS ANALYSIS OF SUBSURFACE DRAINAGE FEATURES BASED ON DESIGN ADEQUACY
• FIELD EVALUATION OF GEOCELL USE IN FLEXIBLE PAVEMENTS
• FINITE-ELEMENT ANALYSIS OF FATIGUE LIFETIME IN PAVEMENTS
• FINITE-LAYER APPROACH TO PAVEMENT RESPONSE EVALUATION
• PAVEMENT DISTRESS AND ROADWAY DAMAGE CAUSED BY SUBSURFACE MOISTURE AND FREEZING TEMPERATURES: CASE HISTORIES FROM ALASKA
• SEASONAL VARIATION OF MOISTURE AND SUBSURFACE LAYER MODULI
• STONE INTERLAYER PAVEMENT DESIGN
• THREE-DIMENSIONAL MODELING OF SPATIAL SOIL PROPERTIES VIA ARTIFICIAL NEURAL NETWORKS
• TUBE SUCTION TEST FOR EVALUATING AGGREGATE BASE MATERIALS IN FROST- AND MOISTURE-SUSCEPTIBLE ENVIRONMENTS
• USING A MULTISEGMENT TIME DOMAIN REFLECTOMETRY PROBE TO DETERMINE FROST DEPTH IN PAVEMENT SYSTEMS