Microscale Peridynamic Simulation of Damage Process of Hydrated Cement Paste Subjected to Tension

Abstract

This work aims to investigate the mechanical properties and crack propagation of cement paste at the micro-level. For this purpose, the peridynamic (PD) method is utilized for the first time to solve the problems of discontinuity in the microstructure of cement paste, such as initiation and propagation of cracks. The effects of various factors on the mechanical properties and microcracks propagation of hydrated cement paste at the micro-scale are investigated using the PD method and computer simulated microstructures, including loading direction, curing age and w/c ratio. The results show that with increasing strain, microcracks mainly form and develop through the outer hydration products, which are the weakest link in the connected solid skeleton of the microstructure; the size and number of microcracks increase during a process of stretching which may result in the decrease of the Young's modulus of hydrated cement paste; microscopically, hydrated cement paste can be considered as an isotropic material; furthermore, lower w/c ratio and longer curing age (or higher degree of hydration) would result in a harder cement paste, a higher tensile strength, and less microcracks. The simulated tensile strength and Young's modulus agree well with previous simulations and experimental results, proving the feasibility of the PD method in microscale studies of cement paste.

Department(s)

Civil, Architectural and Environmental Engineering

Research Center/Lab(s)

INSPIRE - University Transportation Center

Second Research Center/Lab

Center for Research in Energy and Environment (CREE)

Comments

Financial support from National Natural Science Foundation of China under 51678317 , 51420105015 , China Ministry of Science and Technology under 2015CB655100 , Natural Science Foundation of Shandong Province under ZR2017JL024 , The Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China under 161069 , and China Postdoctoral Science Foundation under 2019  M652345 is gratefully acknowledged.

Keywords and Phrases

Cement Paste; Crack Propagation; Curing Age; Mechanical Properties; Micro-Scale; Peridynamics; W/C Ratio

International Standard Serial Number (ISSN)

0950-0618

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2019 Elsevier Ltd, All rights reserved.

Publication Date

01 Dec 2019

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