# Engineering Mechanics

(Joyce) #1

Chapter 12 : Support Reactions  217

``217``

#### Support Reactions

``12.1. INTRODUCTION``

``````In our day-to-day work, we see that whenever
we apply a force on a body, it exerts a *reaction, e.g.,
when a ceiling fan is hung from a girder, it is sub-
jected to the following two forces:``````

1. Weight of the fan, acting downwards,
and

2. Reaction on the girder, acting upwards.
A little consideration will show, that as the fan is
in equilibrium therefore, the above two forces must
be equal and opposite. Similarly, if we consider the
equilibrium of a girder supported on the walls, we

``````* It will also be discussed in the chapter on ‘Laws of
Motion’.``````

# 12

``CHAPTERCHAPTERCHAPTERCHAPTERCHAPTER``

``Contents``

1. Introduction.

6. Methods for the Reactions of
a Beam.

7. Analytical Method for the
Reactions of a Beam.

8. Graphical Method for the
Reactions of a Beam.

9. Construction of Space
Diagram.

10. Construction of Vector
Diagram.

11. Types of End Supports of
Beams.

12. Simply Supported Beams.

13. Overhanging Beams.

14. Roller Supported Beams.

15. Hinged Beams.

16. Beams Subjected to a
Moment.

17. Reactions of a Frame or a
Truss.

18. Types of End Supports of
Frames.

19. Frames with Simply Supported
Ends.

20. Frames with One End Hinged
(or Pin-jointed) and the Other
Supported Freely on Roller.

21. Frames with One End Hinged
(or Pin-jointed) and the Other
Supported on Rollers and