Title:
Control of Thermal and Shrinkage Cracking of Jointless Slab-on-Ground
Author(s):
Sergio Botassi dos Santos, Kennedy Leandro de Souza Neves, and Estevão Alencar Bandeira
Publication:
Materials Journal
Volume:
116
Issue:
3
Appears on pages(s):
13-20
Keywords:
case study; slab-on-ground; thermal and shrinkage cracking
DOI:
10.14359/51712267
Date:
5/1/2019
Abstract:
This paper presents a real 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. The main properties were initially estimated based on the thermal structure behavior to evaluate the volume change effect from early ages to long-term effects. 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. After the concrete placement, the solutions proved to satisfactorily prevent cracks, thus ensuring proper performance of the pool.
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