1.A beam is said to be under-reinforced beam when the amount of reinforcement is less than the proper requirement. In this case, the depth of actual neutral axis will be less than that of the critical neutral axis.

2.A beam is said to be balanced beam when the amount of reinforcement is equal to the proper requirement. In this case, the depth of actual neutral axis will be the same as that of critical neutral axis.

3.A beam is said to be over-reinforced beam when the amount of reinforcement is more than the proper requirement. In this case, the depth of actual neutral axis will be more than the critical neutral axis.