How to Specify
Mechanical splices for rebar are to be NMB SPLICE-SLEEVES filled with SS MORTAR following instructions from Splice Sleeve North America, Inc., Livonia, Michigan.
Examples: NMB SPLICE-SLEEVE 8U-X(PG), 11 U-X(PRE) .The grout shall meet a minimum of 6,500 psi for Type 1, or 9,500 psi for Type 2 performance.
Mechanical rebar splices by means of grout-filled steel sleeves with frusto-conical geometry filled with a non-shrink, high strength grout as specified by the manufacturer to meet the requirements of Type 1 or 2 of ACI 318 or IBC.
Notes regarding AASHTO code requirements: The NMB SPLICE-SLEEVE exceeds the requirements (min. 125%fy) of the AASHTO, Standard Specification for Highway Bridges, Division I- Design, Section 8.32.2 including the new Article 188.8.131.52 in the 16th Edition. This article sets down requirements for fatigue design of mechanical connections. The NMB is listed generically as the "Grout-filled sleeve (without threaded ends), with or without epoxy coated rebar", which is the only coupler in the 18-ksi stress category.