Overview
EN ISO 22476-1:2023 (ISO 22476-1:2022) specifies equipment, procedural and reporting requirements for the electrical cone and piezocone penetration test (CPT / CPTU) used in geotechnical investigation and field testing. The standard covers onshore and nearshore cone penetration testing and fulfils cone and piezocone test requirements referenced in the EN 1997 series for foundation design and site characterization. For offshore CPT requirements, consult ISO 19901-8.
Key topics and technical requirements
- Scope and intent: Defines what to measure and report, and provides recommendations to ensure reliable CPT / CPTU results for geotechnical investigations.
- Specified features: Includes requirements for the type of cone penetration test; cone penetrometer class (see Table 2); test categories (see Table 3); penetration length/depth; ground surface elevation relative to datum; test location relative to fixed reference; and pore pressure dissipation tests (PPDT).
- Equipment and sensors: Requirements for cone penetrometers, friction sleeve, filter element, pushrods, measuring systems and sensors (cone resistance, sleeve friction, pore pressure, inclination, temperature) and thrust machines.
- Data and measurements: Frequency of data recording, measurement of penetration length, raw data handling and required measured parameters (cone resistance, sleeve friction, pore pressure, inclination, temperature).
- Procedures: Guidance on test preparation, pushing procedures, friction-reduction techniques, PPDT execution, test completion and evaluation against test categories.
- Calibration and conformity: Calibration, verification, and cone penetrometer class conformity assessment requirements; maintenance, checks and calibration procedures (normative annexes).
- Reporting: Mandatory reporting elements covering general information, test location, equipment, measured results, corrections and presentation formats.
- Annexes: Informative and normative annexes include suitability of methods, maintenance/checks/calibration, calibration report example, calculation of penetration depth, sleeve friction correction for water pressure, piezocone preparation and friction reduction techniques.
Applications
- Site characterization for foundation design and earthworks
- Stratigraphic profiling and in‑situ soil property measurement
- Liquefaction and settlement assessment using cone resistance and pore pressure data
- Geotechnical baseline reports for construction, dredging and nearshore works
- Quality control of soil improvement and ground investigation programs
Who should use this standard
- Geotechnical and civil engineers
- Field site investigation teams and drilling contractors
- Geotechnical consultants and design offices
- Equipment manufacturers and calibration laboratories
- Regulators and clients specifying geotechnical investigation standards
Related standards
- EN 1997 series (geotechnical design) - referenced compliance requirements
- ISO 19901-8 - requirements for offshore CPT (for offshore applications)
EN ISO 22476-1:2023 is essential for consistent, verifiable CPT/CPTU practice, ensuring reliable cone penetration data for engineering design and geotechnical assessment.
