Mechanisms of Diagonal-Shear Failure in Reinforced Concrete Beams analyzed by AE-SiGMA

• OHNO Kentaro

  Graduate School of Science and Technology, Kumamoto University

• SHIMOZONO Shinichiro

  Graduate School of Science and Technology, Kumamoto University

• SAWADA Yosuke

  Graduate School of Science and Technology, Kumamoto University

• OHTSU Masayasu

  Graduate School of Science and Technology, Kumamoto University

Abstract

Serious shear failures in reinforced concrete (RC) structures were reported in the Hanshin-Awaji Earthquake. In particular, it was demonstrated that a diagonal-shear failure could lead to disastrous damage. However, mechanisms of the diagonal-shear failure in RC beams have not been completely clarified yet. In this study, the diagonal-shear failure in RC beams is investigated, applying acoustic emission (AE) method. To identify source mechanisms of AE signals, SiGMA (Simplified Green's functions for Moment tensor Analysis) procedure was applied. Prior to four-point bending tests of RC beams, theoretical waveforms were calculated to determine the optimal arrangement of AE sensors. Then, cracking mechanisms in experiments were investigated by applying the SiGMA procedure to AE waveforms. From results of the SiGMA analysis, dominant motions of micro-cracks are found to be of shear crack in all the loading stages. As the load increased, the number of tensile cracks increased and eventually the diagonal-shear failure occurred in the shear span. Prior to final failure, AE cluster of micro-cracks was intensely observed in the shear span. To classify AE sources into tensile and shear cracks, AE parameter analysis was also applied. As a result, most of AE hits are classified into tensile cracks. The difference between results obtained by the AE parameter analysis and by the SiGMA analysis is investigated and discussed.

Journal

• Journal of Solid Mechanics and Materials Engineering

  Journal of Solid Mechanics and Materials Engineering 2 (4), 462-472, 2008

  The Japan Society of Mechanical Engineers

Keywords

• Acoustic Emission
• Diagonal-Shear Failure
• Parameter Analysis
• Reinforced Concrete Beam
• SiGMA Analysis

Details

• CRID: 1390001205263569024
• NII Article ID: 130000079204
• DOI: 10.1299/jmmp.2.462
• ISSN: 18809871
• Web Site: http://www.jstage.jst.go.jp/article/jmmp/2/4/2_4_462/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed