Browse > Article

A Study on the Evaluation of Smear Zone by In-situ Tests  

이장덕 (두우건설엔지니어링)
구자갑 (국립 한경대학교 토목공학과)
Publication Information
Journal of the Korean Geotechnical Society / v.19, no.6, 2003 , pp. 207-216 More about this Journal
Abstract
To evaluate the smear zone caused by the drain installation, 10 piezometers were installed in the typical soft ground in the western coastal area of Korea. The dynamic pore water pressure developed during the drain installation was monitored using piezometers installed at a distance of 10cm, 20cm, 30cm, 40cm and 50cm from the location of the drain. The decay of pore pressure with time after pushing piezometers to depths of 5 meters and 7 meters during the drain installation was monitored to assess flow and consolidation characteristics of the soil after disturbance of the soil due to the drain installation. The drain installation results in shear strain and displacement of the soil and it decreases the permeability of the soil. Hence, the comparison between dissipation of the pore water pressure process in 10 pieszometers before as well as after installation of the drain indicated the diameter of disturbance zone and smear zone, which is related to the cross-sectional dimension of the mandrel. In addition, Cone-pressuremeter(CPM) tests were performed to obtain rigidity index of the soil for an interpretation of the dissipation processes. It has been evaluated by in-situ tests that the smear zone is from 3.0 to 3.6 times of the cross-sectional dimension of the mandrel. The hydraulic conductivity expressed in terms of the coefficient of consolidation after the drain installation was calculated from 3 to 8 times decrease evaluated by Teh & Houlsby equation and CPM test results.
Keywords
CPM; Dissipation test; Hydraulic conductivity; PBD; Smear zone;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 Consolidation of Fine Grained Soils by Prefabricated Drains /
[ Hansbo,S. ] / Proc. 10th ICSFE
2 Settlements of Bangna-Bangpakong Highway on Soft Bangkok Clay /
[ Bergado,D.T.;Ahmed,S.;Sampaco,C.L.;Balasubramaniam,A.S. ] / ASCE, Journal of Geotechnical Engineering   DOI
3 Pore Pressure Dissipation after Cone Penetration /
[ Baligh,M.M.;Levadoux,J.N. ] / Report P80-11
4 The Influence of Gological Features of Clay Deposits on the Design and Performance of Sand Drains /
[ Rowe,P.W. ] / Proc. Inst. Civ. Engrs, paper 7058-S
5 Analysis of the Cone Pressuremeter Test in Clay /
[ Houlsby,G.T.;Withers,N.J. ] / Geotechnique   DOI
6 A Theoretial Study on Smear effect Around Vertical Drain /
[ Chai,J.C.;Miura,N.;Sakajo,S. ] / Proc. 14th Int. Conf. Soil Mech. and Found. Engrg.
7 /
[ Lunne,T.;Robertson,P.K.;Powell,J.J.M. ] / Cone Penetration Testing in Geotechnical Practie
8 국내 PBD재의 배수성능과 진공효과에 의한 통수능력 향상에 관한 연구 /
[ 박영목 ] / 한국지반공학회지   과학기술학회마을
9 粘性土水平方向壓密係數決定法 /
[ 小林正樹;水上純一;土田孝 ] / 運輸省港?技術硏究報告書
10 Smear Effects of Vertical Drains on Soft Bangkok Clay /
[ Bergado,D.T.;Asakami,H.;Alfaro,M.C.;Balasubramaniam,A.S. ] / ASCE, Journal of Geotechnical Engineering   DOI
11 인천국제공학 부지 해성 세립토에 대한 CPTU와 DMT 결과 비교 /
[ 김주형;김명모;김영웅;조성민 ] / 한국지반공학회 논문집   과학기술학회마을
12 Analysis of the Piezocone in Clay /
[ Houlsby,G.T.;Tech,C.I. ] / Proc. of the International Symposium on Penetration Testing, ISOPT-1, Orlando
13 Consolidation of Clay by Band-Shaped Prefabricated Drains /
[ Hansbo,S. ] / Ground Engineering
14 Prefabricated Vertical Drains /
[ Rixner,J.J.;Kraemer,S.R.;Smith,A.D. ] / FWHA/RD-86/168
15 The Significance of the Strain Path Analysis in the Interpretation of Piezocone Dissipation Data /
[ Danziger,F.A.B.;Almeida,M.S.S.;Sills,G.C. ] / Geotechnique   DOI   ScienceOn
16 /
[ Baligh,M.M. ] / Journal of the Geotechnical Engineering Division   DOI
17 Pore Pressure Sounding Instrument /
[ Torstensson,B.A. ] / Proceeding of the ASCE Specialty Conference on In-situ Measurement of Soil Properties
18 Consolidation of Fine-Grained Soils by Drain Wells /
[ Barron,R.A. ] / Trans. ASCE
19 Guidelines for Geotechnical Design Using CPT and CPTU /
[ Robertson,P.K.;Campanella,R.G. ] / Soil Mechanics Series