Resonant Column Test for Unsaturated Soils With Suction–Saturation Control

Comprehensive characterization of the small strain shear modulus Gmax of an unsaturated soil specimen during hydraulic hysteresis requires precise control of the stress state, matric suction, degree of saturation, as well as knowledge of the void ratio. This paper describes the details and typical results from a test method which incorporates the axis translation technique for suction control, a flow pump for degree of saturation control, and a vertically oriented proximeter to infer changes in void ratio into a fixed–free resonant column setup. A unique aspect of this test method is the operation of the flow pump to reach equilibrium points on the hysteretic soil–water retention curve (SWRC) for measurement of Gmax. The flow pump, which controls water flow to or from the soil specimen through a high air-entry ceramic disk, is guided using a feedback loop involving the matric suction measured at the boundary of the specimen. Values of Gmax were measured at different equilibrium points on the primary drainage path of the SWRC up to the point of water occlusion, then along a scanning imbibition path of the SWRC. The results indicate a greater shear modulus during imbibition, consistent with trends and magnitudes noted in the technical literature.

• Record URL:
  • https://doi.org/10.1520/GTJ103102
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01496115
• Supplemental Notes:
  • © ASTM International 2011. All rights reserved. This material may not be reproduced or copied, in whole or in part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of the publisher.
• Authors:
  • Khosravi, Ali
  • McCartney, John S
• Publication Date: 2011-11

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 730-739
• Serial:
  • Geotechnical Testing Journal
  • Volume: 34
  • Issue Number: 6
  • Publisher: ASTM International
  • ISSN: 0149-6115
  • EISSN: 1945-7545
  • Serial URL: https://www.astm.org/products-services/standards-and-publications/geotechnical-testing-journal.html

Subject/Index Terms

• TRT Terms: Hysteresis; Percent saturation; Shear modulus; Soil suction; Test procedures; Unsaturated soils; Volume changes
• Uncontrolled Terms: Resonant column testing
• Subject Areas: Geotechnology; Highways; I42: Soil Mechanics;

Filing Info

• Accession Number: 01369852
• Record Type: Publication
• Files: TRIS
• Created Date: May 16 2012 3:04PM