Perfect Frame
The frame, which is composed of such members, which are just sufficient to keep the frame in equilibrium, when the frame is supporting an external load, is known as perfect frame. Hence for a perfect frame, the number of joints and number of members are given as: n = 2j – 3
Imperfect Fram
An Imperfect frame is one which does not satisfies the relation between the numbers of members and number of joints given by the equation n = 2j – 3. This means that number of member in an imperfect frame will be either more or less than (2j-3) It may be a deficient frame or a redundant frame.
Deficient Frame
If the numbers of member in a frame are less than (2j-3), then the frame is known as deficient frame.
Redundant Frame
If the numbers of member in a frame are more than (2j-3), then the frame is known as redundant frame.
