Development Length of Unconfined Conventional and High-Strength Steel Reinforcing Bars

作者：Hosny Amr^*; Seliem Hatem M; Rizkalla Sami H; Zia Paul

来源：ACI Structural Journal, 2012, 109(5): 655-664.

• bond
• development length
• high-strength steel
• reinforcement
• splice length

The development length equation specified by ACI 318-08 and the similar equation recommended by ACI 408R-03 are based on extensive test results using conventional reinforcement conforming to ASTM A615/A615M and A706/A706M. With the development of new ASTM A1035/A1035M high-strength steel reinforcement, several studies have been conducted to examine whether the current equations are applicable for the new high-strength reinforcing steel. These studies have shown that the current equations could, in some cases, overestimate the bond strength of high-strength steel bars. This paper proposes a new equation for the bond strength of unconfined reinforcing bars for all three types of steel. The proposed equation for high-strength steel is compared to extensive test data reported in the literature and is found to be more accurate than ACI 318-08 and ACI 408R-03 equations specified for conventional reinforcement.

• 出版日期2012-10