Continuity of precast beam's bottom rebars through precast column

[Nonlinearer]

In precast beam-column moment connection where precast beam is resting on corbel of precast column and top rebars of beam are made continuous through precast columns in top cast-in-place part of precast composite beam, is it necessary to continue some of the bottom bars of precast beam through precast column to ensure moment connection??
The debate is if bottom bars are not continuous we should take only top screed (cast-in-place) part of the beam for moment connection whereas some opine that if there is no tension at the supprot at bottom, there is no need to continue bottom rebars of precast beam. Bottom rebars continuity would be required in case of reversals where tension occurs at bottom. In normal continuous RC beams there is requirement of 30 percent bottom bars continuity in BS codes. In case of precast beam column connection as mentioned above, can we avoid precast beam's bottom rebars continuity when there is no tension at the bottom??. This will much simplify and speed-up the construction. Please can anybody advise?



IR

 

[hokie66]

There should be no difference in requirements for ductility, robustness, etc. in beam to column connections depending on the material used. There are various methods used in making precast connections moment resisting. When these methods are not used, precast structures sometimes fall down.