SPLICE SLEEVE NORTH AMERICA, INC. Irvine, California   The NMB SPLICE-SLEEVE®, a system for connecting reinforcing bars in concrete, makes it possible to build larger, taller structures more economically in Tilt-Up. It is now being used worldwide for housing, hotels, offices, garages, bridges, sports arenas, and more.   TCA Member Since: 2004

The NMB Splice-Sleeve® is a mechanical coupler for splicing reinforcing bars in precast and tilt-up concrete. The system uses a cylindrical steel sleeve and a portland cement-based high-strength grout. Each of the reinforcing bars to be spliced is inserted halfway into the sleeve and the sleeve is filled with grout. The resulting splice develops tensile and compressive strength well beyond the minimum required by the American Concrete Institute's 318 Building Code. It is accepted by the International Code Council Evaluation Service as a Type 2 coupler, the highest rating for use in all seismic zones.

For columns and walls, before pouring concrete into forms, the sleeves are attached to the main reinforcing bars at one end with the bars protruding from the other end. After curing, the pieces are then lifted and erected in their final position, where they are joined and temporarily braced. The sleeves are filled with grout, and the reinforcing bars effectively become continuous throughout the assembly the next day. For tilt-up construction, the application of NMB’s is expected to simplify the connection details between the wall panels and foundation and allow taller structures.

This method of connecting walls, columns, and beams has been in use in Japan since the 1970s and has been recognized by such organizations as the International Code Council, various state departments of transportation, the New York City Board of Standards and Appeals, and the City of Los Angeles Department of Building and Safety.

This system was invented by Dr. Alfred A. Yee, P.E., President of Applied Technology Corporation in Hawaii. Dr. Yee worked closely with the Japanese division of Master Builders, who originally bought the patent rights and lent their name, NMB (Nisso Master Builders), to the product. Dr. Yee first used his grout-filled splice-sleeves in Honolulu in 1970 to connect precast concrete column-trees in the 38-story Ala Moana Hotel.

Splice Sleeve Japan, Ltd., (SSJL) was formed in 1977 and acquired the rights to the system from NMB. In 1988, Splice Sleeve North America, Inc., (SSNA) was established by SSJL, as a California corporation.

In the series of earthquakes that rocked the world in the mid 1990s, NMB Splice-Sleeves played a heroic role: buildings that had been constructed with them experienced no damage. Thousands of lives were saved in the magnitude 8.2 earthquake on Guam in 1994 and the 7.9 earthquake in Kobe, Japan in 1995.

The 39-story Paramount Tower went up in San Francisco, setting a new U.S. record for the highest building constructed with the NMB Splice-Sleeve. Another record was set soon after in Tokyo where the NMB’s were used for the Shiodome H residential tower, topping out at 56 floors.

From super-high-rise buildings and parking garages to stadiums and bridges, the NMB Splice-Sleeve System offers structural strength and construction speed and economy that builders around the globe are now discovering.