A wavelet-based method to analyze CPT data for geotechnical and geo-environmental site characterization

The applications of cone penetration technology (CPT) in geotechnical and geo-environmental engineering are increasing due to recent advances in electronics and sensors that can be installed on the cone. However, interpretation of CPT data is a complex process and most existing methods are either empirical or semi-empirical. In order to fully utilize the capability of CPT, issues of local feature identification, uncertainty quantification, and scale effects on the interpretation of collected data have to be addressed properly. In this paper, wavelet transform and wavelet variance are used to characterize the essential scales of CPT data, and wavelet transform modulus maxima and phases are used to detect instantaneous frequency change. The scale effects of site stratigraphy determination using CPT data are demonstrated. The results indicate that this wavelet-based approach can provide a promising tool to reduce uncertainties in CPT data interpretation.