Overview
ISO 10406-3:2019 specifies standardized test methods for unidirectional carbon fibre‑reinforced polymer (CFRP) strips used as external-bonded reinforcement on concrete. The standard covers CFRP strips that consist of carbon fibre and a thermoset resin, are manufactured by the pultrusion method, have a high carbon fibre fraction (typically over 60%), and a thickness up to 3 mm. It defines specimen preparation, tensile testing procedures, accelerated laboratory light‑exposure (artificial weathering) tests and reporting requirements for evaluating tensile properties and durability of CFRP strips.
Key Topics and Requirements
- Scope and material limits: Applicable to pultruded CFRP strips, carbon-fibre fraction ≳60%, thickness ≤ 3 mm.
- Specimen geometry and preparation:
- Test piece dimensions (examples in the standard): total length ≥ 200 mm; test length ≥ 100 mm; width typically 10–15 mm (if strip width ≤10 mm, specimen width equals strip width); anchorage length ≥ 50 mm; anchorage thickness 0.5–2 mm.
- Use of bonded anchorage blocks/tabs at both ends to avoid premature bond failure.
- Surface preparation (grinding/blasting) and adhesive bonding procedures for tabs.
- Cutting accuracy: width tolerance within ±1 mm per 100 mm; use diamond or equivalent blades.
- Tensile testing:
- Test machines shall conform to ISO 7500-1 and have capacity beyond expected specimen tensile capacity.
- Use of precision strain gauges/extensometers mounted at the center of the test length to measure elongation and determine Young’s modulus and tensile strength.
- Minimum number of specimens: no fewer than five for statistical relevance.
- Procedures for calculating tensile capacity, tensile strength and Young’s modulus from load–strain curves.
- Durability / accelerated exposure:
- Methods for accelerated artificial exposure (laboratory light sources), preparation of test plates, exposure periods and subsequent tensile tests.
- Calculation of tensile strength retention rate (ratio of post‑exposure to pre‑exposure tensile strength) and visual inspection criteria.
- Reporting: Specified test report content including dimensions, test conditions, results and calculations.
Applications - Who Uses This Standard
- Structural and civil engineers specifying CFRP strengthening for concrete repair and strengthening projects.
- Manufacturers of CFRP strips and pultrusion facilities for quality control and product development.
- Testing laboratories and certification bodies performing material qualification, durability testing and compliance verification.
- Contractors and asset managers implementing external-bonded FRP retrofit systems for bridges, buildings and infrastructure.
Related Standards
Keywords: ISO 10406-3:2019, CFRP strips, carbon fibre‑reinforced polymer, FRP reinforcement of concrete, tensile test methods, pultrusion, tensile strength retention, accelerated artificial exposure.
Open preview (PDF)Fibre-reinforced polymer (FRP) reinforcement of concrete — Test methods — Part 3: CFRP strips