ISO 22477-5:2018

Overview

ISO 22477-5:2018 - Geotechnical investigation and testing - Testing of geotechnical structures - Part 5: Testing of grouted anchors - specifies how to carry out tension tests on grouted anchors installed in the ground. The standard defines three recognized test methods (cyclic tension with displacement measurement, cyclic tension with load-loss measurement, and step-loading with maintained loads), describes required equipment and measurement systems, and prescribes test procedures, result presentation and record content. Note: proof load and acceptance criteria are not set in this document and are provided by EN 1997-1, EN 1537 or relevant national application documents.

Key topics and technical requirements

• Test methods
  • Test Method 1: Cyclic tension loading with measurement of displacement at load stages (displacement-based cyclic test).
  • Test Method 2: Cyclic tension loading with measurement of load loss at load stages (load-loss-based cyclic test).
  • Test Method 3: Step-loading with measurement of displacement under successive maintained tension loads (step-load test).
• Test types
  • Investigation test, Suitability test, Acceptance test - each with tailored loading procedures and reporting requirements.
• Equipment and instrumentation
  • Requirements for reaction system, loading device, load measurement (load cells, calibrations), displacement measurement (extensometers, reference systems), plus time and temperature recording.
• Execution details
  • Site and anchor selection, time between installation and test, test preparation, datum and proof loads, group testing and alternating loading.
• Results and reporting
  • Definitions and presentation of test outcomes; mandatory record content for traceability.
• Informative annexes
  • Methods for calculating creep rate (α), load loss (k), critical creep load (Pc), evaluation of apparent tendon free length, and typical anchor steel properties.

Applications and intended users

ISO 22477-5 is used where reliable performance of grouted anchors must be verified in-situ:

• Geotechnical and structural engineers specifying anchor tests for design validation.
• Construction contractors and specialist anchor installers performing acceptance testing.
• Testing laboratories and inspection bodies carrying out standardized tension tests.
• Project owners, regulators and consultants requiring documented, comparable anchor performance data. Typical applications include rock and soil anchors for retaining structures, foundations, slopes stabilization, and temporary or permanent load-bearing anchors.

Related standards

• EN 1997-1 (Eurocode 7) - geotechnical design rules and national annexes for proof load/criteria.
• EN 1537 - execution of anchored retaining systems (referenced for anchor definitions).
• ISO 22477 series (geotechnical investigation and testing) - related methods and parts.

Keywords: ISO 22477-5:2018, testing of grouted anchors, grouted anchors testing, geotechnical testing, cyclic tension loading, displacement measurement, load loss measurement, step-loading.