In order to study the mechanical characteristics of calcium silicate hydrate (C-S-H), the main component of cement materials, a molecular model with a calcium-to-silicon ratio of 1.67 and a density of 2.4 g/cm3 was constructed based on the Tobermorite model. Then, mechanical properties of C-S-H under compression and tension at varied temperatures were studied by molecular dynamics simulation. Stress-strain relationships, peak stress and Young's modulus of C-S-H at varied tempera-tures were obtained. Results of molecular dynamics simulation show that: peak stress and Young's modulus of C-S-H in both tensile and compressive tests decrease significantly with the increase of tem-perature; peak stress of C-S-H in compression is significantly greater than that in tension; tensile frac-ture pattern of C-S-H in Z-direction changes from plastic failure to brittle failure with the increase of temperature.
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