Under strong winds and at low temperatures, heat loss of hot-mix asphalt mixtures is likely to occur, which leads to temperature segregation. Temperature segregation affects the forming quality and the performance of asphalt pavements. In this study, a phase-change thermal-insulation agent (PCTIA) was prepared for reducing the temperature dissipation. A cooling simulation experiment was performed to test the temperature-dissipation process for an ordinary asphalt mixture and the asphalt mixture mixed with PCTIA (AM-PCTIA). The thermal-insulation effect was analyzed according to the temperature difference and the thermal-insulation extension time. Moreover, two indices—the thermal-insulation accumulated time difference value (IATDV) and thermal-insulation accumulated time difference index (IATDI)—were proposed for evaluating the thermal-insulation ability and efficiency. The results indicated that the temperature at the center of the AM-PATIA was 4 °C higher than that for the ordinary asphalt mixture. The insulation time was prolonged by 29.8 min at the ambient temperature of 15 °C. As the ambient temperature increased, the thermal-insulation effect of the PCTIA improved.

Dry shrinkage test and temperature shrinkage test were experimented to cement stabilized gravel that preserved simulating the actual temperature in freeze soil region.Shrinkage properties were analyzed.It is pointed that the change trend of relative dry shrinkage strain of the earlier and the inchoate preserved simulation sample is basically same.The change trend of dry shrinkage coefficient is evidently different.The worst phase of dry shrinkage strain is the relative water loss ratio between 65% and 80%.Preserving temperature evidently influence the temperature shrinkage of mixture.The temperature shrinkage strain changing speed of the simulation test piece is greater than that of the standard ones.The temperature shrinkage coefficient of the simulation test piece is about 1.5 to 5.0 times of the standard ones,and their changing trends are different.The worst temperature shrinkage phase of cement stabilized gravel in freeze soil region is 0 ℃ to-20 ℃.Change of the shrinkage properties of mixture in freeze soil region is related to the effect of temperature on the strength forming of mixture.The results indicate that quicken the strength forming of cement stabilized gravel in freeze soil region may evidently enhanced the shrinkage-crack resistance of the mixture.

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.