Direct electric curing in high early-strength sodium citrate-doped Portland cement systems for sustainable energy saving applications

Faced with the increasingly severe energy crisis, it is very important to seek a low-energy-consumption accelerated curing method for prefabricated concrete element to save energy in the construction industry. In this research, direct electric curing (DEC) was used to produce high early-strength cement sample, and sodium citrate was used to improve the durability of the paste. Meanwhile, the effects of DEC and traditional accelerated curing methods on the early-age strength of paste and the corresponding energy consumption were compared and discussed. The results indicate that the DEC makes the early-age strength of cement paste higher than that of steam-cured sample, but its energy consumption is only 4% of that of steam curing. Although DEC increases the early-ages strength of the cement sample without reducing its long-term strength, it increases the water absorption and drying shrinkage deformation of the sample. Meanwhile, incorporating sodium citrate to the electric-cured paste can effectively improve its durability by refining the pore structure. The reduction in energy consumption also means a reduction in production costs and carbon emissions. This means that DEC can replace traditional accelerated maintenance methods and improve production & energy efficiency, which may bring a technological change to the modern construction industry.