This document discusses different types of loads and supports that can act on beams. It describes concentrated loads, distributed loads, varying loads, couples, simple supports, roller supports, hinged supports, and combined supports. It also provides an example of calculating support reactions for a beam supported by a hinge and roller, subject to distributed and point loads. The key types of loads and supports are defined, and the process for calculating support reactions by summing forces and taking moments is demonstrated.

1. SUPPORT REACTIONS
BY
GP CAPT NC CHATTOPADHYAY

2. NEED FOR SUPPORT
 THE LOAD CARRYING STRUCTURES
NEED SUPPORTS TO AVOID
-DEFORMATION
-BENDING
-INSTABILITY

3. Types of loads
 Several types of loads can act on beams, such as concentrated loads,
distributed loads, varying loads and couples.
 Concentrated loads are idealized from loads applied on a very small area.
Magnitudes are known .
 Distributed loads are spread along the axes of beams. For example, the
weight of the beam can be assumed as a distributed force.
 Distributed loads are converted into equivalent forces to make the solution
process easier. For vertical loads, the equivalent force is through the
centroid of the distributed load. Thus, if the distributed load is a basic
shape, the centroid is easy to determine without integration.
 Couples are moments applied on the beam. Do not contribute to force .
 Uniform varying Load
In this case the load varies uniformly along the length (gradual increase,
gradual decrease)

4. POINT LOAD

5. UDL
Length = l
Length = L

6. UNIFORMLY VARYING LOAD

7. COMBINED UDL AND UVL
=
W= 1500N/m

8. TYPES OF SUPPORT
SUPPORTS
SIMPLE ROLLER HINGED
• 2 (USUALLY ONE)
ROLLER SUPPORTS
• SUPPORTS ALLOW
FREE EXPANSION
•TAKES VERTICAL
LOADS NORMAL TO
ROLLER PLANE
• 2 OR MORE
VERTICAL
SUPPORTS
• JUST PIVOTS
•TAKES ONLY
VERTICAL LOADS
•2 (USUALLY ONE) HINGED
SUPPORTS
• SUPPORTS TAKE VERTICAL AND
HORI…LOAD
• USUALLY DESIGNED WITH A
ROLLER SUPPORT FOR FREE
EXPANSION OF ONE END
• VERTICAL AND HORI… LOADS
DETERMINE REACTION AND LINE
OF ACTION

9. SIMPLE SUPPORT

10. ROLLER SUPPORT
LOCATION OF
ROLLER BEARING
TO SUPPORT JET
ENGINE ROTOR

11. HINGED SUPPORT
KNEE

12. COMBINED SUPPORT
HINGED SUPPORT ROLLER SUPPORT
DISTRITIBUTED LOAD = w

13. I THINK…. I CAN THINK….

14. Calculate the support reactions

Solution:
First change UDL in to point load.
Resolved all the forces in horizontal and vertical direction. Since roller at B (only one
vertical reaction) and hinged at point B (one vertical and one horizontal reaction).
Let reaction at hinged i.e., point B is RBH and RBV, and reaction at roller support i.e. point
D is RDV Let ΣH & ΣV is the sum of horizontal and vertical component of the forces ,The
supported beam is in equilibrium, hence
ΣH = ΣV = 0
RH = RBH = 0
RBH = 0 ...(i)
ΣV = RBV –50 –5 – RDV = 0
RBV + RDV = 55 ...(ii)
Taking moment about point B
50 × 0.5 – RBV × 0 – RDV × 5 + 5 × 7 = 0
RDV =12 KN .......ANS
Putting the value of RBV in equation (ii)
RBV = 43KN .......ANS
Hence RBH = 0, RDV = 12KN, RBV = 43KN

15. NUMERICAL
 A 9m long beam ABCD is supported
on a hinge at ‘A’ and a roller support
at an angle of 45o at ‘D’. The beam
has a clockwise moment of 9 kNm at
‘B’ and a point load of 6 kN at ’C’. If
the points are equidistant, find the
support reactions.