ISO 22476-16-2024 PDF

Full title and description

Geotechnical investigation and testing — Field testing — Part 16: Borehole shear test. This International Standard specifies the borehole shear test using the phicometer procedure (commonly called the phicometer test) for determination of in situ shear strength parameters (cohesion and angle of internal friction) in a range of natural, fill and artificial soils.

Abstract

This document applies to the phicometer borehole shear test performed in boreholes to derive shear strength properties (cohesion and friction angle). It covers applicable soil types, test limitations (not generally for very soft fines, very loose coarse soils, strong rock or soils with predominant cobbles >150 mm), typical in‑situ resistance ranges for which the test is most representative, and a maximum recommended test depth of 30 m.

General information

• Status: Published.
• Publication date: 25 October 2024 (Edition 1: 2024-10).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 93.020 (Geotechnical engineering).
• Edition / version: Edition 1, 2024.
• Number of pages: 41 pages.

Sources: ISO bibliographic data and publisher metadata.

Scope

The standard specifies the procedure, equipment and interpretation for the borehole shear test (phicometer). It is intended for testing in natural soils, fills and engineered fills that fall within the stated ranges of in‑situ resistance (approximate Ménard pressuremeter p_lM, CPT cone resistance qc and SPT N ranges shown in the standard) and is limited to tests carried out at depths ≤ 30 m. It also describes limitations where the test is not applicable and guidance on assessing representativeness when tests are performed outside the normal application ranges.

Key topics and requirements

• Definition and objectives of the borehole shear (phicometer) test.
• Equipment specification, installation in boreholes and calibration requirements.
• Test procedure: emplacement, loading sequence, measurement and data recording.
• Data interpretation: derivation of cohesion and friction angle from PBST graphs and recommended analysis steps.
• Application limits: unsuitable ground conditions and maximum recommended depth (≤ 30 m).
• Reporting requirements and presentation of results for engineering use.
• Quality assurance, repeatability checks and validation of representativeness when outside typical ranges.

Typical use and users

Used by geotechnical engineers, site investigation contractors, consultants and researchers for in situ assessment of shear strength parameters to support foundation design, slope stability assessments, earthworks and forensic ground investigations. It is applied where borehole access is available and where the phicometer method yields representative data within its application limits.

Related standards

Part of the ISO 22476 series (Geotechnical investigation and testing — Field testing). Closely related parts include ISO 22476-1 (electrical cone and piezocone), ISO 22476-3 (standard penetration test), ISO 22476-4 (Ménard pressuremeter), ISO 22476-7 (borehole jack test) and other field testing parts addressing CPT, pressuremeter, dilatometer and vane testing methods. Users should consult the series for complementary field-testing procedures and cross-reference test applicability.

Keywords

borehole shear test; phicometer; PBST; shear strength; cohesion; friction angle; field testing; geotechnical investigation; in situ testing; ISO 22476.

FAQ

Q: What is this standard?

A: ISO 22476-16:2024 is an international standard that specifies the borehole shear test (phicometer) method for measuring in situ shear strength parameters in soils.

Q: What does it cover?

A: It covers the phicometer test equipment, test procedure, data acquisition, interpretation to obtain cohesion and friction angle, reporting, limitations of applicability and quality assurance for tests performed at depths up to 30 m.

Q: Who typically uses it?

A: Geotechnical engineers, site investigation contractors, consultants and researchers involved in foundation design, slope stability and other ground‑engineering projects where in situ shear strength information is required.

Q: Is it current or superseded?

A: ISO 22476-16:2024 is the current published edition (Edition 1, published October 2024). Users should check national adoption or harmonized versions for any later amendments or regional supersessions.

Q: Is it part of a series?

A: Yes — it is part of the multi‑part ISO 22476 series covering field testing methods for geotechnical investigation; cross‑referencing other parts in the series is recommended for comprehensive site investigation planning.

Q: What are the key keywords?

A: Borehole shear test; phicometer; PBST; shear strength; cohesion; friction angle; in situ testing; geotechnical field methods; ISO 22476.