Reactive molecular dynamics based multiaxial failure analysis of jennite

Abstract

Jennite is one of the key analogs to calcium silicate gel (C-S-H), the main contributor to cement paste’s cohesive strength, which helps in gluing natural aggregates into concrete. The primary role of the glue is to sustain externally applied mechanical loading, preventing the disintegration of concrete. Atomic bonds within the glue are the ultimate receptors of these loads. In this study, the multiaxial failure mechanism of the C-S-H at the nanoscale has been investigated within the framework of molecular dynamics simulation. we have adopted jennite as a simpler representative of C-S-H gel to study the response under uni/multi-axial deformation and the underlying mechanism of failures. The major two mechanisms are the separation of calcium silicate layers and the breakage of covalent silicate chains. The study also presents an ellipsoidal yield surface of failure captured at the molecular scale.