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The early-age cracking of concrete is one of the most critical parameters affecting the performance of concrete structures. It is attributed to both the internal and external influences such as early age restrained shrinkage, thermal deformation as well as the applied load. In this paper, a detailed review of the causes of early-age cracking is first presented, followed by the factors affecting the concrete cracking including raw materials quality problems, improper construction measures, external environmental influences and structural design flaws. Then the preventive measures for concrete cracking are summarized. The potential for the application and development of structural health monitoring and artificial intelligence techniques for early-age cracking of concrete is also discussed. Through the comprehensive review of the early-age cracking of concrete, the research direction for the subsequent research on early-age cracking of concrete is pointed out. The current problems and concerns of concrete cracking are also prospected.

Abstract Supplementary cementitious materials (SCMs) such as fly ash and ground granulated blast furnace slag (GGBFS) are found to control the maximum temperature and the accompanying thermal gradients effectively. However, SCMs also lead to low early age strength development. Thus, it is crucial to understand the cracking behaviour of SCMs-based concrete affected by the mix design parameters. In this paper, the thermal cracking resistance was evaluated using a rigid cracking frame (RCF) with a computer-controlled temperature profile. The temperature profile was determined using the software ConcreteWorks by assuming the centre point of the mass concrete. The free shrinkage frame (FSF) and match-curing oven follow the same temperature profile as RCF to measure the free total deformation and time-dependent mechanical properties of concrete, respectively. An analytical model was proposed to calculate the autogenous shrinkage and the thermal stress separately. A time-dependent cracking risk coefficient allowing to estimate the risk of early age cracking of concrete was also proposed.