Building Design and Construction Handbook - Merritt - Ventech!

CONCRETE CONSTRUCTION 9.95
FIGURE 9.34 Reinforcing bar details for uniformly loaded continuous beams.
At columns, embed alternate bottom bars (at least 50% of the tension-steel area)
a minimum of 6 in., to avoid calculation of development length at 0.125L n.
by splicing the top bars at midspan and the bottom bars at or near the supports.
Splicing the bars with Class A tension lap splices (Art. 9.49.7) is acceptable. (See
Fig. 9.35a.)
For nonperimeter beams, the designer has two choices to satisfy the structural
integrity requirements: (1) provide closed stirrups or (2) make at least one-quarter
of the tension-reinforcement area required for positive moment (�A s/4) at midspan
continuous. Splicing the prescribed number of bottom bars over the supports with
Class A tension lap splices is acceptable. At discontinuous ends, the bottom bars
must be anchored with standard hooks. (see Fig. 9.35b.)
FIGURE 9.35 Reinforcement required to ensure structural integrity of
beams. At least one-sixth of the negative-moment rebars and one-fourth of
the positive-moment rebars should be continuous around the perimeter of
the structure (a), with closed stirrups throughout, except at joints. Class A
tension lap splices may be made at midspan. For nonperimeter beams (b),
one-fourth the positive-moment rebars should be continuous. For clarity,
other rebars are not shown in (a) or(b).