ISO 20290-4:2019

Overview

ISO 20290-4:2019 specifies a laboratory test method to determine the Ten Percent Fines Value (TFV) of aggregates for concrete. TFV gives a relative measure of an aggregate’s resistance to crushing under a gradually applied compressive load. The standard covers two procedures: testing aggregates in a dry condition and in a soaked condition. The method is primarily intended for the 14.0 mm → 10.0 mm size fraction (passing 14.0 mm and retained on 10.0 mm test sieves); Annex A describes recommended approaches for other size fractions.

Key Topics

• Test principle: compact aggregate in a steel cylinder with a freely moving plunger and apply a steadily increasing compressive load. Assess crushing by sieving the crushed material.
• TFV definition & calculation: TFV is calculated from the maximum force Fmax and the percentage m passing the 2.36 mm sieve at Fmax, using the formula: TFV = 14·Fmax / (m + 4) where Fmax is in kN and m is the percentage passing the 2.36 mm sieve (target range 7.5 % to 12.5 %).
• Two test conditions:
  • Dry specimens (oven-dried at 105 ±5 °C, except temperature-sensitive recycled aggregates).
  • Soaked specimens (immersion 24 ±2 h at specified temperatures, blot-dried immediately prior to testing).
• Apparatus & key requirements:
  • Compression testing machine capable up to 500 kN with uniform loading to reach the target in ~10 minutes.
  • Steel cylinder and plunger (nominal 150 mm internal diameter; Annex A describes smaller cylinder option).
  • Tamping rod, balance, cylindrical measure, test sieves (ISO 565 compliant: 14.0 mm, 10.0 mm, and 2.36 mm), oven, trays and sieving/cleaning tools.
• Sampling & specimen preparation: reduce laboratory sample to obtain test portions and three specimens; tamp in layers; guidance on specimen mass and tamping strokes is provided.
• Limitations: comparisons between results for non-standard size fractions and the standard 14–10 mm fraction are not generally possible due to insufficient comparative data. National variations in grading and sizes may apply.

Applications

• Quality control of aggregates supplied for concrete production.
• Assessing suitability of aggregate types (weak vs. strong) for structural and non-structural concrete.
• Comparative testing during material selection, production changes, or forensic investigation of aggregate performance.
• Input to specifications and acceptance criteria in construction contracts and material standards.

Who uses this standard

• Aggregate producers and quarry operators
• Concrete producers and mix designers
• Construction material testing laboratories
• Civil/structural engineers and specification writers
• National standards bodies and conformity assessment organizations

Related Standards

• ISO 565 (test sieves) is normative for sieve specification.
• Other parts of the ISO 20290 series cover additional mechanical and physical test methods for aggregates; consult ISO for the full series listing.

For implementation, consult the full ISO 20290-4:2019 text and your national standards body for any national adaptations or permitted grading variations.