Overview
ISO 1920-10:2010 - Testing of concrete - Part 10: Determination of static modulus of elasticity in compression - specifies a laboratory and in-situ test method for measuring the static modulus of elasticity in compression of hardened concrete. The standard defines specimen geometry, instrumentation, loading procedure, calculation and reporting requirements for reliable measurement of deformation properties used in structural design, material characterization and quality control.
Key topics and technical requirements
- Test principle: apply a basic stress of 0.5 N/mm² (MPa), increase stress steadily to an upper level equal to one-third of the 2:1 cylinder compressive strength (F_c/3), record strains, and compute modulus as the stress increment divided by the corresponding strain increment (E = (σ2 − σ1) / (ε2 − ε1)).
- Specimens:
- Preferred: moulded cylinders 150 mm × 300 mm (L/d = 2). L/d may be 2–4.
- Minimum dimension 100 mm or a multiple of nominal maximum aggregate size (see standard).
- For cast specimens: minimum of 5 moulded specimens (3 for compressive strength, 2 for modulus); for specimens taken from structure, 3 specimens (or 2 where removal risks damage).
- Apparatus & measurement:
- Compression machine conforming to EN 12390-4 (or equivalent national standard); machine must be calibrated (at least annually).
- Strain-measuring devices (extensometers, strain gauges, inductance or vibrating-wire gauges) with gauge length ≥ 2/3 d and ≤ d, accuracy typically ±5×10⁻⁶ (100 mm gauges may have ±10×10⁻⁶).
- Measurements on at least two opposite faces; gauge points positioned equidistant from specimen ends.
- Procedure details: preloading cycles, hold periods (60 s) and consistency checks (individual strains must be within ±20% of mean at σ2).
- Alternative method: continuous measurement during monotonic loading to failure is permitted; the upper stress for modulus can be taken from the test record (Annex A gives an automatic measuring method).
- Results: express modulus in GPa, to three significant digits; report individual and mean values and relevant specimen/test data.
Applications and users
- Used by structural and geotechnical engineers, materials laboratories, construction quality-control teams, researchers, and standards bodies for:
- Determining elastic properties for structural analysis and design.
- Verifying compliance of hardened concrete with specified deformation characteristics.
- Material characterization, comparative studies, and research on concrete behavior under compression.
- In-situ assessment of existing structures using cored specimens.
Related standards
Keywords: ISO 1920-10:2010, static modulus of elasticity, modulus of elasticity in compression, concrete testing, compressive strength, strain measurement, compression testing machine, hardened concrete, test specimens.