Kevin M. Briggs, Yuderka Trinidad González, William Powrie, Simon Butler, Nick Sartain
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引用次数: 0
Abstract
The empirical interpretation of cone penetration test (CPT) cone factors ( N k ) can be subject to considerable variability for clays derived from weathered mudstones, leading to significant deviations in the estimation of undrained shear strength ( S u ). This paper presents a comparison of triaxial and CPT data from a site investigation in clays derived from weathered mudstones in central England. Corrected cone factors ( N kt,UU ) were derived from a one-to-one comparison of 94 pairs of unconsolidated, undrained triaxial and CPT data from equivalent depths. The performance of the cone factors was evaluated using a training set (75 pairs) and a test set (19 pairs). A parametric study was used to explore the variability of N kt,UU , quantified using the coefficient of variation (COV Nkt,UU ), for varied separation distance thresholds ( D s ) between individual triaxial and CPT data. The absolute deviation between the laboratory shear strength ( S u(Lab) ) and that predicted from CPT profiles (S u(CPT) ) was not sensitive to N kt,UU values in the range 25 < N kt,UU < 31. The parametric study showed that D s could be increased from 50 to 250 m, to include more data pairs for estimates of N kt,UU , without substantially increasing COV Nkt,UU .
期刊介绍:
Quarterly Journal of Engineering Geology and Hydrogeology is owned by the Geological Society of London and published by the Geological Society Publishing House.
Quarterly Journal of Engineering Geology & Hydrogeology (QJEGH) is an established peer reviewed international journal featuring papers on geology as applied to civil engineering mining practice and water resources. Papers are invited from, and about, all areas of the world on engineering geology and hydrogeology topics. This includes but is not limited to: applied geophysics, engineering geomorphology, environmental geology, hydrogeology, groundwater quality, ground source heat, contaminated land, waste management, land use planning, geotechnics, rock mechanics, geomaterials and geological hazards.
The journal publishes the prestigious Glossop and Ineson lectures, research papers, case studies, review articles, technical notes, photographic features, thematic sets, discussion papers, editorial opinion and book reviews.