Properties and Microstructure of HPC with Lithium-Slag and Fly Ash

Abstract

High performance concrete (HPC) was prepared using lithium-slag and fly ash,which are the industrial waste in Xinjiang Province,China,and its mechanical properties,crack resistance impermeability of concrete. The results showed that: lithium slag can well improve the mechanical properties of concrete, after adding fly ash, in the total dosage of 20%, the improving effect on the mechanical properties is the best; in the total dosage of 50%, its performance improvement of cracking resistance and impermeability is particularly evident, and can significantly improve the interface of concrete structures and products. At early hydration, admixture involved secondary hydration reaction generated in the interface area silicon ratio of calcium silicate hydrate and dense structure,which reduces the crystal content of loose AFt and Ca(OH)2, improving the performance of concrete mechanical and impermeability, particularly, the formation of needle AFt compensate the shrinkage of concrete and improve the performance of concrete early cracking.