A clean strategy of concrete curing in cold climate: Solar thermal energy storage based on phase change material

In this paper, a novel strategy of concrete curing was developed by solar thermal energy storage based on phase change material (PCM), in order to prevent concrete from frost damage at early age and promote the rapid growth of concrete strength in cold climate. This method utilized huge latent heat of thermal energy storage layer (TESL) containing PCM to achieve continuous curing of concrete at positive temperature, and transparent insulation layer (TIL) was set outside so that TESL can fully absorb a large amount of thermal energy through solar radiation to complete repeated phase transition between day and night. Moreover, a numerical method was proposed to guide the reasonable design of TESL under different climatic conditions and it turned out that the optimum thickness of TESL ranged from 0.87 cm to 4.86 cm. Experiment results indicated that concrete specimen cured by the novel curing strategy achieved an excellent curing temperature history and it took only 60 h to reach the design strength. In addition, economic evaluation results suggested low cost, prominent energy saving and emission reduction performance of the proposed curing method in the whole service cycle. This work provided new insights into an efficient and clean solution to achieving the rapid construction of concrete en-gineering in cold climate.