Moisture Distribution Model to Predict Matric Suction in Unbound Granular Materials as a Function of Fines Content

The existence of water in the layers of unbound road aggregates significantly influences the performance of pavement structure. Thus, the ability to estimate volumetric water content and its capillary effect is very important. Several models have been suggested to link the matric suction of unbound materials to their water retention properties. In this paper, an analytical moisture distribution model is proposed by using packing theory-based framework for unbound granular materials. The framework was previously developed by the authors of this paper and identifies two basic components of unbound granular materials skeleton: primary structure (PS) - a range of interactive coarse grain sizes that forms the main load-carrying network in granular materials and secondary structure (SS) - a range of grain sizes smaller than the PS providing stability to the aggregate skeleton. In the new moisture model, water was considered to be stored as both menisci water between SS particles and water that fully filled in very small voids. In order to validate the model, predicted results are compared with measured matric suction of a granite material with different gradations. The results showed that the model is capable of predicting the experimentally measured matric suction values for a range of gradations.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFP60 Standing Committee on Engineering Behavior of Unsaturated Soils. Alternate title: A Moisture Distribution Model to Predict Matric Suction in Unbound Granular Materials as a Function of Fines Content.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Yideti, Tatek Fekadu
  • Birgisson, Bjorn
  • Jelagin, Denis
• Conference:
  • Transportation Research Board 95th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2016-1-10 to 2016-1-14
• Date: 2016

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 17p
• Monograph Title: TRB 95th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Aggregate gradation; Fines (Materials); Granular materials; Mathematical models; Moisture content; Validation
• Uncontrolled Terms: Fines content; Matric suction; Moisture distribution; Unbound granular materials
• Subject Areas: Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways;

Filing Info

• Accession Number: 01590351
• Record Type: Publication
• Report/Paper Numbers: 16-3327
• Files: TRIS, TRB, ATRI
• Created Date: Feb 16 2016 4:01PM