Analysis of frames:
- A frame is a structure made of several bars/ rods welded / rivetted together
- The bars are angle irons/ channels of “i” or “t” sections. These are called members
- On application of load on to the structure, the members remain loaded with tensile/ compressive load
- Members under tension are called “tie”
- Members under compression are called “strut”
- The structure formed by the members (tie/ strut) is called “truss”
- Extensively used in roof, bridge, sheds etc.
- Structure is made of members just sufficient to keep it in equilibrium, when loaded without any change of shape
- N = 2j – 3 where ‘n’ is the number of members and ‘j’ no of joints
- It is efficient and optimized structure.
- Structure is made of members more or lesser than the minimum numbers necessary to keep it in equilibrium, when loaded
- N ≠ 2j – 3
- N > 2j – 3 redundant
- N < 2j – 3 deficient
- Inefficient structure