Calibration of cone penetrometers according to International Organization for Standardization requirements

Abstract

Detailed requirements for calibration of piezocone penetrometers are incorporated in standards published by International Organization for Standardization (ISO). The use of these standards can provide input for comparisons of cone penetration test (CPT) systems deployed in practice by means of cone penetrometer classes. It is important that parties specifying or supplying CPT data take note of the implications of the new requirements and the opportunities and benefits of appropriate selection of cone penetrometer classes. In addition, the information available from calibration and verification of a particular cone penetrometer can provide input into estimation of uncertainties of data points in CPT profiles used for design of structures. This paper focusses on background information about topics considered for development of the ISO requirements. These topics included (1) practical and economical test methods achievable in a calibration laboratory, (2) assessment of differences in exposure conditions applied in the calibration process and site conditions likely to be encountered during actual cone penetration testing, and (3) cone penetrometers that incorporate ancillary sensors and algorithms for reducing the influence of temperature on CPT results.