Rebar splice lengths in Structural Walls

[tipover]

I am designing a shear wall (in a high seismic zone), which does not require boundary elements, and have a question about the rebar splice lengths. ACI 318-02 section 21.7.2.3 states section 21.5.4 should be used to determine the splice length. Section 21.5.4 bases development length for a straight bar on a factor times the development length of a std hook. The factor could be either 2.5 or 3.5 depending on bar location. However section 21.5.4.3 states that an additional factor of 1.6 should be used if the rein is not in the confined core. Does that mean the development length for all rein in a structural wall should be multiplied by 1.6? PCA notes on ACI 318-02 example 29.6 appears not to follow section 21.5.4.3. Any advice would be appreciated.

 

[UcfSE]

I read that to say if a straight bar is terminated at a joint then the portion of the straight bar that is not within the confined core must be increased by 1.6. If you had 12" sticking out past the confined core then you would increase that 12" to 1.6*12 = 19.2" >> 20". I believe that is what the commentary is saying. That of course doesn't mean I am necessarily correct. What do you think? Also, 21.5 is for joints in special moment frames, and 21.5.4 is for development length, not lap splice length. It looks like 21.4.3.2 has some provisions for lap splices in special moment frame members.

 

[tipover]

I agree that section 21.5 is for joints, but shear wall section 21.7.2.3 refers to section 21.5.4.

The rebar splice length I want is for a straight bar in a structural wall without boundary elements(no confined core).