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ACI 318-02 Building Code and PCA Notes

Building Code Requirements for Structural Concrete (318-02) and Commentary (318R-02) from the American Concrete Institute was released in January of 2002. The following are the major changes introduced in the latest Code:

• The existing Appendix B, Unified Design Provisions for Reinforced and
  Prestressed Concrete Flexural and Compression Members, is moved to the main body of the 2002 Code. The corresponding 1999 provisions are moved to form new Appendix B.



• Modified load and strength reduction factors are moved from Appendix C, Alternative Load and Strength Reduction Factors, to the main body of the 2002 Code. The ASCE 7 load factors in the current Appendix C were updated to conform to ASCE 7-98, and the corresponding strength reduction factors were re-evaluated and modified. Current load combinations and strength reduction factors in Chapter 9 of ACI 318-99 are moved to new Appendix C.



• New provisions are provided in Chapter 21, Special Provisions for Seismic Design, for the design of precast in special moment frames, special structural walls, frame members not proportioned to resist forces induced by earthquake motions, intermediate moment frames, and intermediate precast structural walls.
  
  Additional requirements are provided in Chapter 21 for hoops in interconnections, and shear strength of two-way slab systems that are used as intermediate moment frames. Also, changes have been made that remove barriers for the use of high-strength concrete.



• The existing Appendix A, Alternate Design Method, has been removed from ACI 318-02. The new Appendix A, Strut-and-Tie Models, provides provisions for strut-and-tie models, which are especially useful when designing concrete members where plane-section assumptions of beam theory do not apply.



• New provisions for cast-in-place and post-installed anchors are provided in new Appendix D, Anchorage to Concrete.

The PCA publication Notes on ACI 318-02 Building Code Requirements for
Structural Concrete with Design Applications will assist engineers in the proper application of ACI 318-02. Numerous examples illustrate the new design provisions. Click here for more information or to order.