FIELD TRIALS OF CEMENTITOUS BACKFILL

Type 1 granular material is generally used for backfilling trenches in roads and footways; it needs compaction. A recent Transport Research Laboratory (TRL) study of defects in reinstated trenches showed that, in 90% of cases, the compaction level was incorrect and, in 50%, compaction was insufficient. Thus research is needed to investigate the use of materials requiring little or no compaction. This paper reports the results of field trials conducted on PFA:sand:cement, Lytag:cement, and Type 1 granular material. It first surveys the results of some earlier tests conducted from 1980 on. Before the field work, a large-scale laboratory model trench, made of plywood and perspex, was filled with the mixes chosen for the trials, and compression tests were conducted. The field trial was conducted to compare the behaviour of the two artificial materials and conventional Type 1 granular subbase backfill. Surface profiles were measured after trench reinstatements, using a two-dimensional profile-measuring device. Core samples from trial trenches were recovered one year after replacement, and their elastic moduli were measured. Falling weight deflectometer (FWD) tests were conducted one year after trench construction, to study the effects of various backfill materials on trench performance. Five conclusions are presented.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/02656868
• Corporate Authors:

  INSTITUTION OF HIGHWAYS & TRANSPORTATION

  6 ENDSLEIGH STREET
  LONDON,   United Kingdom  WC1H 0DZ
• Authors:
  • GHATAORA, G
  • ALOBAIDI, I M
  • COOMBS, R
• Publication Date: 2000-6

Language

• English

Media Info

• Features: References;
• Pagination: p. 13-5
• Serial:
  • HIGHWAYS & TRANSPORTATION
  • Publisher: INSTITUTION OF HIGHWAYS & TRANSPORTATION
  • ISSN: 0265-6868

Subject/Index Terms

• TRT Terms: Aggregates; Building materials; Cement; Compaction; Defects; Deflection; Excavation; Excavations; Fly ash; Highways; Measurement; Repairing; Research projects; Sand; Scale models; Structural models; Tests; Walkways
• ITRD Terms: 4577: Aggregate; 4758: Cement; 3686: Compaction; 5238: Defect (tech); 5586: Deflection; 5155: Excavation (process); 4580: Fly ash; 2720: Footway; 2755: Highway; 4555: Material (constr); 6136: Measurement; 6205: Model (not math); 3635: Repair; 8557: Research project; 4105: Sand; 6255: Test
• Subject Areas: Bridges and other structures; Geotechnology; Highways; Research;

Filing Info

• Accession Number: 00798022
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD
• Created Date: Sep 8 2000 12:00AM