Development of Specification for Accelerated Approval Process of Flowable Fill Mixtures

The flowable fill is a family of self-compacting, cementitious materials used primarily as an alternate backfill in lieu of compacted soil. In general, from the applications point of view, the flowable fill mixes can be divided into two categories: removable fills (mixes that require future excavation) and non-removable fills. The specifications for the removable type of flowable fill typically include set limits for the minimum compressive strength, the maximum compressive strength and the density. As an example, the flowable fill approval process currently used by the Indiana Department of Transportation (INDOT) requires that a trial batch be produced by the contractor and tested by INDOT at 28 days to verify that the proposed flowable backfill mix design (FBMD) meets the minimum and maximum unconfined compressive strength (UCS) requirements given in the specification. Since any changes (other than routine moisture fluctuations) require both the completion of a new trail batch and its 28 days strength determination, there was a need to develop a 28 days strength prediction capabilities based on the early age testing to shorten the FBMD approval process. This paper presents a proposed set of FBMD approval requirements which are based on 3 and 14 days blow count number from the Lightweight Dynamic Cone Penetrometer. In the proposed approach, the requirement for 28 days compressive strength was replaced by the removability modulus, which includes early age compressive strength and density of the backfill material.


  • English

Media Info

  • Media Type: CD-ROM
  • Features: Figures; References; Tables;
  • Pagination: 16p
  • Monograph Title: TRB 86th Annual Meeting Compendium of Papers CD-ROM

Subject/Index Terms

Filing Info

  • Accession Number: 01045449
  • Record Type: Publication
  • Report/Paper Numbers: 07-2302
  • Files: TRIS, TRB
  • Created Date: Feb 8 2007 6:59PM