Recent advance of chemical admixtures in concrete

Recent advance on chemical admixtures and their influence on the concrete properties is summarized. The conformational properties of PCE molecules both in solution and on the surface of cement have been studied by computational simulations. Then the effect of molecular structure of PCE on the compatibility and rheological properties of cementitious materials is discussed. The research progress on admixtures to mitigate the shrinkage and cracking risk of concrete is also introduced, including magnesia based expansive agent (MEA), super-absorbent polymers (SAP), and a novel starch-based materials temperature rise inhibitor (TRI). Finally, the development of C-S-H PCE nano composites and their effect on the early age hydration of cementitious materials is reviewed. Advanced quantitative micro-analytical methods and computational modelling are helping us to understand the action mechanism of chemical admixtures and leading to the performance based molecular and microstructure design, which strongly promote the application of admixtures in high performance concrete.