Manufacturing, fabrication, and transportation limitations make it impossible to provide full length continuous bars in most reinforced concrete structures. Therefore proper splicing of rebars becomes essential to the integrity of reinforced concrete. There are three basic ways to splice bars: lap splices, mechanical connections, and welded splices. Of the three, lap splicing is the most common and usually the least expensive. If lap splices are impossible or impractical, the engineer will choose either welded or mechanical splices. The purpose of this article is to identify the different types of proprietary mechanical splices commonly available in the United States, and to outline some of their advantages and disadvantages.
Most modern mechanical splicing devices align and secure the joined rebar ends in an in-line connection suitable to meet appropriate splice requirements. Both compression and tension splicing devices rely on mechanical interlock to accomplish this. The most popular methods or devices are: metal-filled sleeves; mortar-or grout-filled sleeves; swaging or forging, both hot and cold; threading; friction or clamping.