May 2012
Intermediate to advanced
485 pages
10h 45m
English
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12.2 TYPES OF FRAMES
The simplest frame is a triangle which has three members and three joints (pin-jointed).
Although there are many types of frames, which can be thought of, the frames may be grouped under two classes viz.,
- Perfect frames
- Imperfect frames
12.2.1 Perfect Frames
A perfect frame may be defined as that one which is made up of members just sufficient to keep the frame in equilibrium, when loaded, without any change in the shape.
The simplest example of a perfect frame is a triangle. It is to be noted that the shape will not be distorted when the structure is loaded (Figure 12.1(a)). Thus, for three jointed frame, there should be three members to prevent distortion. If it is needed to increase a joint to this triangular frame, ABC, ...