%0 Journal Article
%T Methodology for Obtaining Optimal Sleeve Friction and Friction Ratio Estimates from CPT Data
%A Erick Baziw
%J International Journal of Geosciences
%P 290-303
%@ 2156-8367
%D 2023
%I Scientific Research Publishing
%R 10.4236/ijg.2023.143015
%X Cone penetration testing
(CPT) is a cost effective and popular tool for geotechnical site
characterization. CPT consists of pushing at a constant rate an electronic
penetrometer into penetrable soils and recording cone bearing (</span><i><span style=\"font-family:Verdana;\">q</span><sub><span style=\"font-family:Verdana;\">c</span></sub></i><span style=\"font-family:Verdana;\">),
sleeve friction (</span><i><span style=\"font-family:Verdana;\">f</span><sub><span style=\"font-family:Verdana;\">c</span></sub></i><span style=\"font-family:Verdana;\">) and dynamic pore pressure (</span><i><span style=\"font-family:Verdana;\">u</span></i><span style=\"font-family:Verdana;\">)
with depth. The measured </span><i><span style=\"font-family:Verdana;\">q</span><sub><span style=\"font-family:Verdana;\">c</span></sub></i><span style=\"font-family:Verdana;\">, </span><i><span style=\"font-family:Verdana;\">f</span><sub><span style=\"font-family:Verdana;\">s</span></sub></i><span style=\"font-family:Verdana;\"> and </span><i><span style=\"font-family:Verdana;\">u</span></i><span style=\"font-family:Verdana;\"> values are utilized to estimate soil type and associated soil properties. A
popular method to estimate soil type from CPT measurements is the Soil Behavior
Type (SBT) chart. The SBT plots cone resistance vs friction ratio, </span><i><span style=\"font-family:Verdana;\">R</span><sub><span style=\"font-family:Verdana;\">f</span></sub></i><span style=\"font-family:Verdana;\"> [where: </span><i><span style=\"font-family:Verdana;\">R</span><sub><span style=\"font-family:Verdana;\">f</span></sub></i><span style=\"font-family:Verdana;\"> = (</span><i><span style=\"font-family:Verdana;\">f</span><sub><span style=\"font-family:Verdana;\">s</span></sub></i><span style=\"font-family:Verdana;\">/</span><i><span style=\"font-family:Verdana;\">q</span><sub><span style=\"font-family:Verdana;\">c</span></sub></i><span style=\"font-family:Verdana;\">)100%].
There are distortions in the CPT measurements which can result in erroneous SBT
plots. Cone bearing measurements at a specific depth are blurred or averaged
due to </span><i><span style=\"font-family:Verdana;\">q</span><sub><span style=\"font-family:Verdana;\">c</span></sub></i><span style=\"font-family:Verdana;\"> values being strongly influenced by soils within 10
to 30 cone diameters from the cone tip. The </span><i><span style=\"font-family:Verdana;\">q</span><sub><span style=\"font-family:Verdana;\">c</span></sub><span style=\"font-family:Verdana;\">HMM</span></i><span style=\"font-family:Verdana;\"> algorithm
was
%K Cone Penetration Testing (CPT)
%K Optimal Estimation
%K Geotechnical Site Characterization
%K Sleeve Friction
%K Cone Bearing
%K Friction Ratio
%K Iterative Forward Modelling (IFM)
%K Soil Behavior Type (SBT)
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=123873