Why we provide Anchor Bar in a single RC beam?

It is done for two reasons :

1. To provide support for lateral reinforcement or shear reinforcement in the form of stirrups so they could be held in place.
2. When sufficient bond strength is not available due to insufficient development length, Anchorage bars are used to add up to the development length because they can be longer since they are bent.

Anchor bars provided for the compression side of single RC beams. It is provided to hold or support transverse reinforcement bars.

Anchor bar in single RC ream is provided to hold vertical stirrups.

Vertical stirrups are designed to resist shear force.

We use 8 or 10 dia for anchor bar in beam.

Anchor bars are the bars which are given on compression side to hold the stirrups or lateral reinforcements and the main bars.