The American Concrete Institute (ACI) has released a paper called Control of Thermal and Shrinkage Cracking of Jointless Slab-on-Ground.
ACI says the paper presents a case study concerning the analysis of the cracking risk of a large reinforced concrete slab-on-ground with 9.84 in. (250 mm) of thickness and approximately 9257 ft2 (860 m2) of area.
“It was designed to prevent effects of severe environment conditions over the life span as thermal and drying shrinkage. This slab is a pool floor without expansion joint—jointless—to avoid leakage and early deterioration of the structure,” ACI adds.
The main properties were initially estimated based on the thermal structure behaviour to evaluate the volume change effect from early ages to long-term effects.
According to ACI, “The proposed solutions to reduce the volume change effects of concrete were carried out in three parts: improvements in structural design; optimization of the concrete mixture; and adjustments in the construction process.”
The solutions proved to satisfactorily prevent cracks after the concrete placement, ensuring proper performance of the pool, ACI concludes.
This paper was written by Sergio Botassi dos Santos, Kennedy Leandro de Souza Neves, and Estevão Alencar Bandeira.
