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Title: Fatigue enhancement of concrete beam with ECC layer

Abstract

The pseudo strain-hardening behavior of Engineered Cementitious Composites (ECC) is a desirable characteristic for it to replace concrete to suppress brittle failure. This widespread use of ECC in the industry is, however, limited by its high cost. To achieve higher performance/cost, ECC can be strategically applied in parts of a structure that is under relatively high stress and strain. In this paper, layered ECC-concrete beams subjected to static and fatigue flexural loads were investigated by experiments. The static test results showed that the application of a layer of ECC on the tensile side of a flexural beam increased its flexural strength and the degree of improvement increased with the thickness of ECC applied. In addition, the layer of ECC enhanced the ductility of the beam and the failure mode changed from brittle to ductile. Under four-point cyclic loading, the ECC layer significantly improved the fatigue life of the beam. Moreover, in comparison to plain concrete beams, layered ECC beams could sustain fatigue loading at a larger deflection without failure. The great improvement in fatigue performance was attributed to the effectiveness of ECC in controlling the growth of small cracks. The experimental findings reflect the feasibility of using ECC strategically inmore » critical locations for the control of fatigue crack growth.« less

Authors:
 [1];  [2];  [3]
  1. Department of Civil Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China). E-mail: ckleung@ust.hk
  2. Department of Civil Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)
  3. Department of Civil Engineering, Tsinghua University, Beijing, 100084 (China)
Publication Date:
OSTI Identifier:
20995382
Resource Type:
Journal Article
Resource Relation:
Journal Name: Cement and Concrete Research; Journal Volume: 37; Journal Issue: 5; Other Information: DOI: 10.1016/j.cemconres.2007.01.015; PII: S0008-8846(07)00037-3; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BEAMS; COMPARATIVE EVALUATIONS; CONCRETES; CRACK PROPAGATION; CRACKS; DUCTILITY; FAILURES; FATIGUE; FLEXURAL STRENGTH; LAYERS; PERFORMANCE; STRAIN HARDENING; STRAINS; STRESSES

Citation Formats

Leung, Christopher K.Y., Cheung, Y.N., and Zhang Jun. Fatigue enhancement of concrete beam with ECC layer. United States: N. p., 2007. Web. doi:10.1016/j.cemconres.2007.01.015.
Leung, Christopher K.Y., Cheung, Y.N., & Zhang Jun. Fatigue enhancement of concrete beam with ECC layer. United States. doi:10.1016/j.cemconres.2007.01.015.
Leung, Christopher K.Y., Cheung, Y.N., and Zhang Jun. Tue . "Fatigue enhancement of concrete beam with ECC layer". United States. doi:10.1016/j.cemconres.2007.01.015.
@article{osti_20995382,
title = {Fatigue enhancement of concrete beam with ECC layer},
author = {Leung, Christopher K.Y. and Cheung, Y.N. and Zhang Jun},
abstractNote = {The pseudo strain-hardening behavior of Engineered Cementitious Composites (ECC) is a desirable characteristic for it to replace concrete to suppress brittle failure. This widespread use of ECC in the industry is, however, limited by its high cost. To achieve higher performance/cost, ECC can be strategically applied in parts of a structure that is under relatively high stress and strain. In this paper, layered ECC-concrete beams subjected to static and fatigue flexural loads were investigated by experiments. The static test results showed that the application of a layer of ECC on the tensile side of a flexural beam increased its flexural strength and the degree of improvement increased with the thickness of ECC applied. In addition, the layer of ECC enhanced the ductility of the beam and the failure mode changed from brittle to ductile. Under four-point cyclic loading, the ECC layer significantly improved the fatigue life of the beam. Moreover, in comparison to plain concrete beams, layered ECC beams could sustain fatigue loading at a larger deflection without failure. The great improvement in fatigue performance was attributed to the effectiveness of ECC in controlling the growth of small cracks. The experimental findings reflect the feasibility of using ECC strategically in critical locations for the control of fatigue crack growth.},
doi = {10.1016/j.cemconres.2007.01.015},
journal = {Cement and Concrete Research},
number = 5,
volume = 37,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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