TY - JOUR
T1 - Evaluation of k0 of granular soils using DMT indices
AU - Choi, Sung Kun
AU - Lee, Moon Joo
AU - Choi, Young Min
AU - Lee, Woojin
N1 - Funding Information:
Received 8 April 2010; accepted 6 September 2010. This paper is supported by a Korea University Grant, and by a Construction Core Technology Program (C104A1000009-06A0200-00800) under the KICTEP grant. Address correspondence to Woojin Lee, Professor, School of Civil, Environmental, and Architectural Engineering, Korea University, Seoul, 136-713, Korea. E-mail: woojin@ korea.ac.kr
PY - 2011/4
Y1 - 2011/4
N2 - A series of CPTs and DMTs are performed in the calibration chamber in order to develop methods that estimate the coefficient of at-rest earth pressure (K0), which is an indirect measure evaluating the stress history of granular soil. Among DMT indices and the qc value, KD is observed to be the most sensitive to the stress history while qc and ED show the similar trend of change as the vertical stress and stress history. The relation of Baldi et al. (1986) appears to be applicable for only NC sands as it does not include the term representing the effect of horizontal effective stress. The relations suggested in this study, KD=K0 χ(ED/σ́m)δ and KD/K0a0(ED/pa)a1(σ́m/pa)a2, are observed to provide comparable accuracy in K0 values with those of Jamiolkowski and Robertson (1988) and Mayne (1995, 2001), regardless of the stress history. Suggested relations use only DMT indices while Jamiolkowski and Robertson (1988) require both CPT and DMT results, and Mayne (1995, 2001) needs both the CPT result and the OCR value. Although the adoption of OCR in Mayne (1995, 2001) offers a considerable improvement in the accuracy of the K0 value, it is not considered practical since the inclusion of both soil property (OCR) and index parameters in an empirical correlation provides excessive redundancy.
AB - A series of CPTs and DMTs are performed in the calibration chamber in order to develop methods that estimate the coefficient of at-rest earth pressure (K0), which is an indirect measure evaluating the stress history of granular soil. Among DMT indices and the qc value, KD is observed to be the most sensitive to the stress history while qc and ED show the similar trend of change as the vertical stress and stress history. The relation of Baldi et al. (1986) appears to be applicable for only NC sands as it does not include the term representing the effect of horizontal effective stress. The relations suggested in this study, KD=K0 χ(ED/σ́m)δ and KD/K0a0(ED/pa)a1(σ́m/pa)a2, are observed to provide comparable accuracy in K0 values with those of Jamiolkowski and Robertson (1988) and Mayne (1995, 2001), regardless of the stress history. Suggested relations use only DMT indices while Jamiolkowski and Robertson (1988) require both CPT and DMT results, and Mayne (1995, 2001) needs both the CPT result and the OCR value. Although the adoption of OCR in Mayne (1995, 2001) offers a considerable improvement in the accuracy of the K0 value, it is not considered practical since the inclusion of both soil property (OCR) and index parameters in an empirical correlation provides excessive redundancy.
KW - At-rest coefficient of earth pressure
KW - Dilatometer test
KW - Granular soil
KW - Horizontal stress index
KW - Stress history
UR - http://www.scopus.com/inward/record.url?scp=79957643801&partnerID=8YFLogxK
U2 - 10.1080/1064119X.2010.525141
DO - 10.1080/1064119X.2010.525141
M3 - Article
AN - SCOPUS:79957643801
VL - 29
SP - 117
EP - 130
JO - Marine Georesources and Geotechnology
JF - Marine Georesources and Geotechnology
SN - 1064-119X
IS - 2
ER -