Micro-mechanical properties of C–S–H modified by various carbon nanotubes and the correlation with the nano/micro-structures

This study is to explore the micro-mechanical properties of C–S–H modified by various carbon nanotubes and the correlation with the nano/micro-structures. The results show that carboxyl-functionalized single-walled carbon nanotubes provide the great template for the growth of C–S–H and reduce the porosity and surface defects of C–S–H particles. The highly ordered and dense layered structure of C–S–H greatly improves its micro-mechanical properties. In addition, the functional groups (–COOH) of functionalized carbon nanotubes can combine with the Ca–O bond of C–S–H to change the interlayer spacing of C–S–H, and the effects are particularly significant at low Ca/Si. Graphical abstract