Prevention of Thermal Cracking in Concrete at Early Ages

Early age fracture properties of microstructurally-designed mortars

“…2 material properties are still developing and the rate of shrinkage and thermal deformations is high [3,4]. A precise knowledge of the mechanical properties, and in particular of the fracture properties, is at the basis of virtually every approach for modeling crack initiation and propagation.…”

Parametric Assessment of Stress Development and Cracking in Internally Cured Restrained Mortars Experiencing Autogenous Deformations and Thermal Loading

“…As such, the failure stress (average section stress at the onset of unstable cracking) was reduced with decreasing elastic modulus. Due to the additional effect of stress relaxation, the effect of elastic modulus on reducing the average stress at failure of the specimen became more 8 Advances in Civil Engineering 14 με/ • C was used for all mortar mixtures in this study, it must be mentioned that the COTE is highly dependent on the aggregate composition, aggregate volume, moisture content, and the presence of LWA particles [2,45,46]. It has been reported that a concrete with lightweight aggregates generally has a smaller COTE than that of a concrete with normal weight aggregates [36][37][38].…”

“…When volume changes caused by the heating or cooling of concrete are restrained, residual tensile stresses can develop [1,2]. These residual stresses can result in cracking if they reach the tensile strength of the concrete.…”

“…Restrained thermal and autogenous shrinkage are known as two of the primary contributions to the potential for cracking in concrete members at early ages [2]. Autogenous shrinkage stresses and thermally induced residual stresses can be approximated as being additive [4].…”

Thermal Stress Analysis for Early Age Mass Concrete Members

“…At that time, the considerations were the concrete temperature and stiffness when the concrete mixture turns from semi-liquid state to solid state. The major difficulty was that the degree of restraint in a 3-D body could not be calculated using the conventional method (Springenschmid, 1998). More recently, 3-D stress modeling became easier using the modern computer technology.…”