Determination of Double-G Fracture Parameters of Post-Fire Concrete

Abstract:

Double-G fracture model was recently proposed based on the conception of energy release rate to describe the fracture behaviour on cracked concrete. Two fracture parameters, i.e., the initiation fracture energy release G_Icⁱⁿⁱ and the unstable fracture energy release G_Ic^un, are termed to distinguish the different crack propagation stages undergoing during the whole fracture process in concrete. In present work, following the Double-G fracture model at ambient temperature, the residual Double-G fracture parameters of post-fire concrete is elaborately introduced. Totally ten temperatures varying from 20oC to 600oC and the specimens size of 230×200×200 mm with initial-notch depth ratios 0.4 were considered. Wedge-splitting method is adopted to measure the loadcrack mouth opening displacement curves (PCMOD) and double-G fracture parameters are experimentally determined.

• Periodical: Advanced Materials Research (Volume 746)
• Pages: 348-351
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.746.348
• Online since: August 2013
• Authors: Zhou Dao Lu, Neng You
• Keywords: Double-G Fracture Mode, Energy Release Rate, Post-Fire, Wedge-Splitting Method

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