Reinforced concrete walls: IBC 2000 & ACI 318-2001

New provisions for seismic design of reinforced concrete structural walls were incorporated into the 1994 version of the Uniform Building Code and have been updated in the 1997 UBC. The new provisions apply primarily to slender walls, and a displacement-based design methodology is used. The format of the UBC provisions offer significant advantages over previous design formats; however, there are still areas where design guidance is lacking. These areas include design of stout walls, design of walls with openings, and use of high-strength materials. In an attempt to address these needs, as well as other minor issues, a joint ACI-SEAOC task group was formed to develop wall design provisions for ACI 318-2001, with the hope that these provisions would be adopted by the IBC in 2000 (or 2003). The following is a progress report based on input from the task group.