Marine soil behaviour classification using piezocone penetration test (CPTu) and borehole records
Tóm tắt
Several piezocone penetration test (CPTu)-based soil behaviour classification systems (SBCs) have been developed for standard sites, where clays, silt, and sand dominate. However, problems can occur when applying the SBCs to offshore sites, where the marine soils may be decomposed from rocks or mixed with artificial fills. This study evaluates the accuracy of six CPTu-based SBCs for marine soils at a site offshore Hong Kong based on 16 CPTu soundings with 25 367 data points by comparing them with composition-based SBCs from borehole records in the vicinity of each sounding. The soil types are determined from six common CPTu-based SBCs. The interpretation of CPTu data is first performed to generate soil type variables comparable to borehole data, followed by a cross-validation study. The soil classification performance of each SBC is quantified by the weighted kappa coefficient and the Kendall correlation coefficient between the soil types generated by the CPTu-based and composition-based SBCs. The classification accuracy for each soil type is also evaluated via the root mean squared error and the mean absolute error. The classified soil types from the CPTu data are associated with a median degree of consistency, indicating the need for combining CPTu-based and composition-based SBCs for marine soil classification.
Từ khóa
Tài liệu tham khảo
Baligh M.M., 1980, Journal of Geotechnical Engineering, 106, 447
Eslami A., 2004, Iranian Journal of Science and Technology Transaction B - Engineering, 28, 69
GEO. 1997. Guide to rock and soil descriptions (GEOGUIDE 3), Geotechnical Engineering Office, Hong Kong.
ISO. 2014. Petroleum and Natural Gas Industries - Specific Requirements for Offshore Structures - Part 8: Marine soil investigations. International Standard ISO 19901-8:2014. International Organization for Standardization, Geneva.
Lumb, P. 1977. The marine soils of Hong Kong and Macau. In A memorial collection of selected papers and memoir of Professor Peter Lumb. Edited by A.T. Yeung. Professor Lumb Trust Fund, Hong Kong, pp. 665–680.
Lunne, T., Robertson, P.K., and Powell, J.J.M. 1997. Cone penetration testing in geotechnical practice. Blackie Academic and Professional, London.
Maunsell, G. 1991. Chek Lap Kok Airport: Geotechnical report for the design of the site preparation. Airport Authority Project Technical Library Ref. Nos. 50001716 and 50001485.
Norman, G.R., and Streiner, D.L. 2008. Biostatistics: the bare essentials. PMPH, USA.
Olsen, R.S. 1994. Normalization and prediction of geotechnical properties using the cone penetration test CPT. Ph.D. dissertation, University of California, Berkeley, Calif.
Senneset, K., and Janbu, N. 1985. Shear strength parameters obtained from static cone penetration tests. In Proceedings, Strength Testing of Marine Sediments; Laboratory and In Situ Measurement, ASTM Special Technical Publication, STP, 883, pp. 41–54. 10.1520/STP36328S.
Tumay, M.T., Boggess, R.L., and Acar, Y. 1981. Subsurface investigation with piezocone penetrometer. In ASCE GSP on Cone Penetration Testing and Experience, St Louis, Mo., pp. 325–342.
Yeung, A.T., and So, S.T. 2001. Geotechnical engineering properties of Hong Kong marine clays. In Soft soil engineering. A.A. Balkema Publishers, the Netherlands, pp. 695–700.
Yip, K.L. 2001. An assessment of mud consolidation in a marine disposal pit. In Soft soil engineering. A.A. Balkema Publishers, Netherlands, 279pp.