Title: Mechanical Connections of Reinforcing Bars

Author(s): ACI Committee 439

Publication: Structural Journal

Volume: 88

Issue: 2

Appears on pages(s): 222-237

Keywords: bolted connections; connections; couplers; dowels; sleeves; reinforced concrete; reinforcing steels; splicing; Design

DOI: 10.14359/3079

Date: 3/1/1991

Abstract:
Properly designed splices are a key element in any well-executed design. The lap splice, when conditions permit and when it will satisfy all requirements, is generally the most common method for splicing reinforcing bars. However, when lap splices are undesirable or impractical, or when their use is not permitted by the design code or specification, mechanical or welded connections should be used to splice the reinforcing bars. The objective of this report is to provide engineers and contractors with basic information about mechanical connections and the types of proprietary mechanical connection devices currently available, but not to state conditions of acceptance, or to endorse or rate a particular mechanical connection device over another. These mechanical connection devices are proprietary, and the information herein provided by the connector manufacturers has been compiled, but none of the information has been specifically verified by this committee. Consequently, the relative merits of the different mechanical connection devices are neither noted nor compared. However, the information given is useful, because it is not presently available elsewhere in such an assembled and detailed format. An attempt was made to include all the mechanical connection devices generally commercially available in North America at the time the report was written. However, it must be realized that some devices new in the market may not be included, merely due to ignorance of their existence at the time of writing. Reasons to use mechanical connections are discussed, as well as various engineering considerations that must be made when specifying mechanical connections, such as the need to avoid notch effects in seismic joints that could result in the bar rupturing at one location before it yields generally elsewhere. Mechanical connection devices are described in terms of configuration, procedure for connecting, clearance requirements, and other characteristics. Illustrations of the various mechanical connection devices are included.