TITLE:
Technique for Estimating the Cone Bearing Smoothing Parameters
AUTHORS:
Erick Baziw
KEYWORDS:
Cone Penetration Testing (CPT), Geotechnical Site Characterization, Optimal Estimation, Iterative Forward Modelling (IFM), Monte Carlo Techniques, Calibration
JOURNAL NAME:
International Journal of Geosciences,
Vol.14 No.7,
July
25,
2023
ABSTRACT: Cone penetration testing (CPT) is an extensively
utilized and cost effective tool for geotechnical site characterization. CPT
consists of pushing at a constant rate an electronic cone into penetrable soils
and recording the resistance to the cone tip (qc value). The
measured qc values (after correction for the pore water
pressure) are utilized to estimate soil type and associated soil properties
based predominantly on empirical correlations. The most common cone tips have
associated areas of 10 cm2 and 15 cm2. Investigators also
utilized significantly larger cone tips (33 cm2 and 40 cm2)
so that gravelly soils can be penetrated. Small cone tips (2 cm2 and 5 cm2)
are utilized for shallow soil investigations. The cone tip resistance measured
at a particular depth is affected by the values above and below the depth of
interest which results in a smoothing or blurring of the true bearing values.
Extensive work has been carried out in mathematically modelling the smoothing
function which results in the blurred cone bearing measurements. This paper
outlines a technique which facilitates estimating the dominant parameters of
the cone smoothing function from processing real cone bearing data sets. This
cone calibration technique is referred to as the so-called CPSPE algorithm. The mathematical details of the CPSPE algorithm are outlined
in this paper along with the results from a challenging test bed simulation.