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Indexed by:Journal Papers

Date of Publication:2015-12-30

Journal:CONSTRUCTION AND BUILDING MATERIALS

Included Journals:SCIE、EI、Scopus

Volume:101

Page Number:440-446

ISSN No.:0950-0618

Key Words:Micro carbon fibers; Macro steel fibers; Nano carbon black; Conductive concrete; Fractional change in impedance; Freezing and thawing damage

Abstract:The effect of freeze-thaw cycles on concrete is of great importance for durability evaluation of concrete structures in cold regions. In this paper, damage accumulation was studied by following the fractional change of impedance (FCI) with number of freeze-thaw cycles (N). The nano-carbon black (NCB), carbon fiber (CF) and steel fiber (SF) were added to plain concrete to produce the triphasic electrical conductive (TEC) and ductile concrete. The effects of NCB, CF and SF on the compressive strength, flexural properties, electrical impedance were investigated. The concrete beams with different dosages of conductive materials were studied for FCI, N and mass loss (ML), the relationship between FCI and N of conductive concrete can be well defined by a first order exponential decay curve. It is noted that this nondestructive and sensitive real-time testing method is meaningful for evaluating of freeze-thaw damage in concrete. (C) 2015 Elsevier Ltd. All rights reserved.