| Equipment | Requirement | |-----------|-------------| | | Must be rigid, non-absorbent, and resistant to corrosion. Dimensional tolerance: ±0.5% of nominal size. Internal surfaces must have a roughness depth ≤ 3.2 µm. Moulds showing dents, warping, or wear beyond tolerance must be retired. | | Vibrating table | Frequency: 50 Hz ± 3 Hz; Amplitude: 0.5 mm ± 0.1 mm for cubes (0.8 mm for cylinders). Compliance must be verified annually. | | Compacting bar | Circular cross-section (e.g., 16 mm or 25 mm diameter depending on aggregate size), with a hemispherical tip. Mass and dimensions specified in the standard. | | Curing tank | Must maintain water temperature at 20°C ± 1°C (or ±2°C for lower grades). Water must be saturated with lime (to prevent leaching of calcium hydroxide from specimens). | | Humidity cabinet | For air curing: Must maintain 20°C ± 2°C and ≥95% relative humidity. |
C. They must be protected from shock, vibration, and moisture loss (e.g., covered with polyethylene sheeting). Final Curing bs en 12390-2:2019
After compaction, strike off the excess concrete using a straightedge (trowel or plate). For cubes, the surface should be (convex) before final smoothing. The finished surface must be flat within 0.05 mm per 100 mm (checked using a straightedge and feeler gauges). | Equipment | Requirement | |-----------|-------------| | |