Time-dependent behavior of bond between reinforcement and concrete
Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Osaka University|
OHNO Yoshiteru Osaka University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (30029194)
|Project Period (FY)
1992 – 1993
Completed(Fiscal Year 1993)
|Budget Amount *help
¥2,200,000 (Direct Cost : ¥2,200,000)
Fiscal Year 1993 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1992 : ¥1,900,000 (Direct Cost : ¥1,900,000)
|Keywords||Long-term deflection / Crack width / Sustained loading / Bond creap / Shrinkage / Slippage of steel / Shape of rib / Bond analysis / 鉄筋コンクリート / はり / 鉄筋 / コンクリート / 付着応力とすべり関係 / 持続載荷 / かぶり厚さ|
1. Relationship of bond stress-slip between concrete and deformed bar under susutained loading :
(1) The relationships between the bond stress and the slip under sustained loading were investigated and modeled based on the result of the prism tests.
(2) Time dependent behavior of the distribution of the steel strain and the additional end slips of steels in the prisms were analyzed by using the bond stress-slip model.
2. Additional deflection in reinforced concrete contilever beams due to slippage of bar at fixed edge under sustained loading :
(1) Bond analysis equations for members on which defferent end bending moment acts were also presented. The analysis used the model of the relationships between bond stress and slip proposed in the part 1. Crack widths and deflections that occured by the slippage of steel were calculated by the bond analysis.
(2) The increase in end slip was dominated by shrinkage of concrete and was scarcely influenced by the magnitude of steel stress.
(3) The deflection in the cantilever beams increased remarkably within one day of sustained loading. The long-term deflection was influenced significantly by the end slip of steel.
(4) Time-dependent behavior of the tension prisms and the cantilever beams was analyzed sufficiently and accurately by considering the change in the relationship between bond stress and slip under sustained loading and creep and shrinkage of concrete.
3. A equation of long-term crack width was obtained by the bond analisys : A additional crack width due to creep of compressive concrete, bond creep and shrinkage of concrete between cracks was considered in the equation.
Research Output (13results)