This code provides specific guidelines for the construction of mass concrete structures, primarily dams. It focuses heavily on managing the heat of hydration, temperature control, the use of exceptionally large aggregates (up to 150mm), and construction joint detailing to prevent thermal cracking in massive concrete pours.
Code of Practice for General Construction of Plain and Reinforced Concrete for Dams and Other Massive Structures
Quick Reference Values
maximum aggregate size150 mm (for mass concrete interior)
minimum curing period14 days
slump mass concrete25 mm to 50 mm
max placement temperatureTypically restricted to limit peak hydration temperature (often 15°C to 20°C placement)
Practical Notes
Temperature control is the most critical aspect of mass concrete. Pre-cooling of aggregates or substituting mixing water with flaked ice is often mandatory.
Embedded cooling pipes (post-cooling) may be required in very massive pours to circulate cold water and extract hydration heat.
Rapid surface cooling of mass concrete must be avoided to prevent steep thermal gradients and cracking. Insulation during curing may be necessary.