Title:
Bond-Splitting Strength of Reinforced Strain-Hardening Cement Composite Elements with Small Bar Spacing
Author(s):
Toshiyuki Kanakubo and Hiroshi Hosoya
Publication:
Structural Journal
Volume:
112
Issue:
2
Appears on pages(s):
189-198
Keywords:
beam bond test; bond splitting; confinement effect; cylinder model; pullout bond test; tensile strength
DOI:
10.14359/51687228
Date:
3/1/2015
Abstract:
Strain-hardening cement composites (SHCCs) show excellent
mechanical behavior that is characterized by tensile strain hardening and multiple fine cracks. A suitable application of SHCC for bond improvement involves reducing the cover thickness and bar spacing of the main bars. To investigate the bond behavior of reinforced SHCC elements and to propose a predicting method for bond strength, the pullout bond test and beam bond test are conducted in which small cover thickness and bar spacing are used. The results of the pullout bond test show that the bond strength of SHCC is higher than that of conventional concrete, which is expected by the “partly-cracked elastic stage” of the cylindrical model by Tepfers. It is considered that the tensile stress distribution of SHCC surrounding main bar corresponds to the “plastic stage.”
The results of the beam bond test also show that the bond strength of SHCC has a higher value. A prediction methodology is proposed as the summation of the bond strength exhibited by SHCC and the confinement of lateral reinforcement.
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