The standard requires specimens to be cast in at least two layers, though the exact number depends on the specimen size and the compaction method used. Step 1: Placing the Concrete Fill the mold in equal layers. For a standard cube, two layers are typically sufficient.
Using a rod or bar, typically tamping at least 25 times uniformly per layer for a 100mm cube.
While the standard primary focus is on "standard curing" to verify the potential strength of a mix design, it also acknowledges "site curing." Site-cured specimens are treated as closely as possible to the actual structure they represent. These are often used to determine when formwork can be safely removed or when post-tensioning can occur. However, site-cured results cannot be used for official compliance with the 28-day characteristic strength requirements unless specifically permitted. Conclusion bs en 12390-2:2019
BS EN 12390-2:2019 Testing Hardened Concrete: Making and Curing Specimens for Strength Tests
Based on industry experience, several common errors arise when implementing BS EN 12390-2:2019: The standard requires specimens to be cast in
Ensure the molds are clean, properly assembled, and thinly coated with a release agent. No excess oil should pool at the bottom of the mold. 3. Molding the Test Specimens
The standard outlines the lifecycle of a test specimen from the moment it is cast until it is ready for testing: Using a rod or bar, typically tamping at
Before placing concrete, clean the internal surfaces of the molds thoroughly. Apply a thin coat of non-reactive release oil to prevent the concrete from sticking. Ensure all joints are tightly sealed to prevent water leakage. 2. Sampling and Filling
If two identical batches of concrete are cured at different temperatures or compacted poorly, their 28-day compressive strengths can vary significantly. Following BS EN 12390-2:2019 safeguards structural projects against artificial test failures, preventing costly project delays, material rejections, and legal disputes. Equipment Specifications
| | Minimum Tamps per Layer | |----------------|------------------------------| | 100 mm cube | 25 tamps | | 150 mm cube | 35 tamps |