State of the Art on Prevention and Control Measures of Thermal Cracks in Mass Concrete

Mass concrete is prone to temperature cracks at an early age due to concentrated hydration heat, significant temperature gradients, and complex constraints, which affect structural durability and service safety. This paper reviews the relevant measures for preventing and controlling such temperature cracks, analyzing that the cracks are caused by the coupling effects of hydration heat, temperature gradients and stress distribution, material properties, environmental factors, and structural dimensions. It elaborates on two types of prevention and control measures: material optimization (low-heat cement, mineral admixtures, chemical admixtures, phase change materials, etc.) and construction process improvement (reasonable placement, cooling systems, external thermal insulation). Among these, phase change materials (PCMs) have become a research focus due to their active temperature regulation function of “peak shaving and valley filling”. This paper also introduces temperature, stress, and crack width monitoring technologies, as well as monitoring-based feedback control and intelligent systems. It summarizes the progress of numerical simulations in temperature field, stress field, and cracking prediction, with particular emphasis on their role in improving the understanding and prevention of early-age thermal cracking. The review further identifies shortcomings in multi-factor coupling mechanisms and integrated material–construction design, and proposes future research directions—such as low-heat-of-hydration binders, PCM optimization, and intelligent monitoring integration—to support more effective crack-control practices in mass concrete.