Investigation on stress variation in soil surrounding a soil nail during installation and pull-out

Li Jun Su, Hong Jian Liao, Jianhua Yin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

Pull-out strength of a soil nail is an important parameter in the design of a soil nailing system. The pull-out strength is determined by the normal stress acting on the soil nail surface during pull-out. The variation of normal stress in soil surrounding a drill-and-grout soil nail during drilling, grouting and pull-out is studied through both laboratory pull-out tests and numerical simulation. It is found that for a drill-and-grout soil nail, most of the normal stress in the soil surrounding the hole is released after drilling. For a soil nail grouted under low pressure, the normal stress does not substantially recover after the nail is installed. During pull-out, the normal stress acting on the nail increases with the increase in pull-out distance because of the constrained dilatancy of the soil surrounding the nail, which eventually increases the pull-out resistance. It is indicated that the dilatancy of the soil is very important to a drill-and-grout soil nail. For soils with low dilatancy, further measures, such as high pressure grouting should be employed to compensate the released stress during drilling.
Original languageChinese (Simplified)
Pages (from-to)124-128
Number of pages5
JournalYantu Lixue/Rock and Soil Mechanics
Volume32
Issue numberSUPPL. 1
Publication statusPublished - 1 Apr 2011

Keywords

  • Finite elements
  • Normal stress
  • Pull-out strength
  • Soil nail

ASJC Scopus subject areas

  • Geotechnical Engineering and Engineering Geology
  • Soil Science
  • Civil and Structural Engineering

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