THE MEASUREMENT OF REINSTATEMENT BACKFILL QUALITY BY A NON-INTRUSIVE METHOD . FIELD TESTING IN ENGINEERING GEOLOGY. PROCEEDINGS OF THE TWENTY-FOURTH ANNUAL CONFERENCE OF THE ENGINEERING GROUP OF THE GEOLOGICAL SOCIETY, SUNDERLAND POLYTECHNIC, SEPTEMBER 4-8 1988

This article describes an investigation to obtain a non-intrusive method for measuring the quality of reinstated backfill. The method involves the measurement of Rayleigh type surface waves using moveable accelerometers, which provide an indirect evaluation of the stiffness properties of the reinstated material. The tests are currently being undertaken in a purpose built laboratory trench facility, on yellow Basalt Permian sand, under a range of carefully controlled compaction levels. The laboratory based trench is an above ground timber construction, with uniformly compacted sand in layers of approximately equal thickness at or near the optimum moisture content. The results obtained on a newly reinstated water surface trench of backfilled type 2 granular material are also presented. The method assumes that the effective depth of propagation of the Rayleigh wave is one half the wavelength within an isotropic level half space. The applicability of this analysis to the waves under question has been assessed and justified by measurements made using buried accelerometers. Value of dry density and impact value are presented as well as the surface wave velocity results. The correlation is assessed between measured surface wave velocities and compacted effort, defined either as the number of passes per layer (N) or, by a new parameter, the ratio of N to the mean layer thickness. Sensitivity analyses are also undertaken and show that Rayleigh type wave velocity are a much more sensitive measure of the degree of compaction than either dry density or impact value measurements. For the covering abstract of the conference see IRRD 832042.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0903317516
• Corporate Authors:

  GEOLOGICAL SOCIETY PUBLISHING HOUSE

  UNIT 7, BRASSMILL ENTERPRISE CENTRE, BRASSMILL LANE
  BATH,   United Kingdom  BA1 3JN
• Authors:
  • WINTER, M G
  • SELBY, A R
• Publication Date: 1990

Language

• English

Media Info

• Pagination: p. 275-285
• Serial:
  • Publication of: GEOLOGICAL SOCIETY PUBLISHING HOUSE
  • Publisher: GEOLOGICAL SOCIETY PUBLISHING HOUSE

Subject/Index Terms

• TRT Terms: Backfilling; Density; Governments; Measurement; Pavements; Pits; Public service; Quality assurance; Repairing; Sand; Service agencies; Stiffness; Test procedures; Trench backfill
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00607166
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• ISBN: 0-903317-51-6
• Files: ITRD, TRIS
• Created Date: Mar 31 1991 12:00AM