Question

Explain support reaction? What are the different types of support and their reactions?

Answer 1

When a number of forces are acting on a body, and the body is supported on another body, then the second body exerts a force known as reaction on the first body at the points of contact so that the first body is in equilibrium. The second body is known as support and the force exerted by the second body on the first body is known as support reaction. 

There are three types of support; 

1. Roller support 

2. Hinged Support 

3. Fixed Support 

1. Roller Support: Beams end is supported on rollers. Reaction is at right angle. Roller can be treated as frictionless. At roller support only one vertical reaction.

2. Hinged (Pin) Support: At a hinged end, a beam cannot move in any direction support will not develop any resisting moment, but it can develop reaction in any direction. In hinged support, there are two reaction is acting, one is vertical and another is horizontal. i.e., RH and RV

3. Fixed Support: At such support the beam end is not free to translate or rotate at fixed end there are three reaction a horizontal reaction (R_H), a vertical reaction(R_V), and moment(M)

14.3.5 Rocker Support: Only one reaction i.e., R_H.