Bs En 12390-2:2019 [cracked] Official

: Guidelines for safely moving specimens from the site to the laboratory without causing internal damage. Why It’s Important

| Mistake | Consequence | How to Avoid | |---------|-------------|---------------| | Using moulds out of tolerance (worn, warped) | Resulting cubes can be oversized (lower strength) or undersized (higher false strength). | Annual mould measurement log. | | Not covering specimens for first 24 hours | Surface drying → lower strength, cracking. | Use rigid plastic lids or cling film immediately. | | Incorrect rodding – too few strokes or bar of wrong diameter | Incomplete compaction → voids and low density. | Use rodding templates and trained operators. | | Water tank temperature not monitored or out of range (e.g., 23°C) | Faster strength gain – false pass for early age, but may also cause weaker late strength. | Continuous temperature logger with alarm. | | Tap water without lime | Surface softening → lower crush results by 5-15%. | Add calcium hydroxide powder to tank water. | | Testing specimens not demoulded flat – rocking on platens | Eccentric loading → variable results. | Check flatness before testing; cap or grind if necessary (per BS EN 12390-3). | bs en 12390-2:2019

Using a rod or bar, typically tamping at least 25 times uniformly per layer for a 100mm cube. : Guidelines for safely moving specimens from the