Inferring Spatial Variation of Soil Classification by Both CPT and Borehole Data
Part Of
Geotechnical Special Publication
Journal Volume
2023-July
Journal Volume
2023-July
Journal Issue
GSP 345
Journal Issue
GSP 345
Start Page
142
End Page
151
ISSN
08950563
Date Issued
2023
Author(s)
Farahbakhsh, Hassan Kamyab
Abstract
Soil boundary delineation is an important task in geotechnical site characterization. It can be achieved by extracting borehole samples, conducting laboratory tests, and classifying them according to soil classification system such as the Unified Soil Classification System (USCS). However, borehole samples are sparse in space, so the delineation of soil boundaries is challenging. In practice, soil boundary delineation is sometimes achieved by conducting multiple cone penetration test (CPT) soundings. Because CPT provides nearly continuous records in the vertical direction, the soil boundaries at the soundings may be identified from the Ic (soil behavior−type index) profiles. However, given the Ic value of a soil, its USCS classification is not 100% certain. It is unclear whether the boundaries identified by Ic reflect the actual boundaries defined by USCS classification. The purpose of this paper is to propose a novel framework of inferring the spatial variation of USCS classification (e.g., sand, silt, and clay) based on both CPT and borehole data. With past experiences on the Ic-USCS correlation from other sites, it is possible to combine site-specific CPT and borehole information to infer the site-specific spatial variation of USCS classification. Once the spatial variation of USCS classification is inferred, the soil boundaries can be identified. The uncertainties for the spatial variation of USCS classification as well as soil boundary identification are quantified through Bayesian analysis.
Event(s)
Geo-Risk Conference 2023: Innovation in Data and Analysis Methods, 23 July 2023 - 26 July 2023, Arlington
SDGs
Publisher
American Society of Civil Engineers (ASCE)
Type
conference paper