Proceedings of the Korean Geotechical Society Conference (한국지반공학회:학술대회논문집)
- 1999.10a
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- Pages.81-86
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- 1999
Determination of Smear Zone by Field CPT Test
현장CPT시험에 의한 스미어존의 범위 산정
Abstract
The installation of vertical drains by means of a mandrel causes significant remolding of the subsoil, especially in the immediate vicinity of the mandrel. Thus, a zone of smear will be developed with reduced permeability and increased compressibility. This paper is mainly concerned with a field study to investigate the effect of smear due to vertical drain installation. In the present study, a field smear test was conducted to assess the extent of the smear zone around the vertical drain. The extent of the smear zone around a vertical drain was evaluated from the CPT results. CPT test was carried out to some distance around the mandrel installation. The test results revealed that a smear zone was estimated to be 3.6~5.3 times of the mandrel diameter.