详情

Develop/Refine Design Provisions for Headed and Hooked Reinforcement

项目名称：	Develop/Refine Design Provisions for Headed and Hooked Reinforcement
摘要：	The usefulness of reinforced concrete is dependent on sufficient anchorage between concrete and reinforcing steel. Sufficient anchorage occurs when reinforcing steel is embedded into the concrete a distance referred to as the development length. When this length of embedment is achieved the reinforcing steel is expected to reach or exceed stresses beyond yield. Geometric constraints within structural members may prevent straight lengths of reinforcement from developing their yield strength, such as straight bars being terminated within a beam-column joint. In these cases, the addition of a hook or headed bar attachment provides a more efficient anchorage mechanism compared to straight bars. Both hooked and headed bars have shorter development lengths than straight bars. However, the current American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications (9th edition) has not developed standard details for headed reinforcement in bridge structures. In addition, current AASHTO LRFD design provisions for hooked bars are adapted from the American Concrete Institute (ACI) 318-14 Building Code Requirements for Structural Concrete. Considerable revisions to the current ACI 318-19 specification for the design of hooked reinforcement, which require increased lengths (50 to 70 percent longer) relative to previous code cycles, necessitates Texas Department of Transportation (TxDOT) to revisit its current design practice for hooked reinforcement. This research seeks to provide TxDOT with clear and concise design guidance for engineers to use both hooked and headed bar attachments in TxDOT bridge structures. The research teams will accomplish this through large-scale experimental testing of specimens with hooked and headed bars representative of TxDOT bridge structures and current design practice.
状态：	Active
资金：	999401
资助组织：	Texas Department of Transportation
管理组织：	Texas Department of Transportation
项目负责人：	Schwerdt, Tom
执行机构：	Texas A&M Transportation Institute<==>University of Texas at San Antonio
主要研究人员：	Skillen, Kinsey
开始时间：	20220901
预计完成日期：	20260228
主题领域：	Bridges and other structures；Design；Highways