This document discusses shear forces and bending moments in structural elements like beams. It defines shear force as a unaligned force that pushes parts of a structure in different directions. Bending moment is the reaction induced in a structural element when an external force causes it to bend. The document describes different types of beams and loads and how to calculate bending moments using the moment of a force equation.

1. STRUCTURE

2. Shear Force
• Shear force is unaligned force pushing one part
of body in one direction and other in other
direction.
• When forces are aligned in each other they are
compression forces
• When forces are opposite to each other it is
tension force.

3. • The cantilever method was derived to calculate
and analyse shear forces and moments
developed in different members like beams and
columns of frame or structure due to lateral
loads.
• The lateral loads includes wind load and
earthquake load which must be taken into
consideration while designing the building.
• The point assumed in this method are that the
point of contraflexure is located at the mid point
of vertical as well as horizontal members and
that the direct stresses in the columns are
proportional to distance from cental axis.

5. • Shear force is a force acting in a direction
perpendicular to the extension of substance as
for example pressure of air along the front of an
airplane wing .
• Shear force often result in shear strain.

6. • Beam : Structural horizontal member resting on
support to carry vertical loads .
• It carry tensile load.
• Types of beam :
• Cantilever beam.
• Simply supported beam.
• Overhanging beam.
• Proped cantilever beam.
• Fixed beam.
• Continuous beam.

7. • Cantilever beam: This type of beam has fixed
end on one end and free end on other.
Eg : Balcony.
• Simply Supported beam: This type of beam has
support on both ends .
This support are called hinge.
Eg: classrooms, public places.
• Overhanging beam : The supports are not at the
end but at some distance from end.
Depth,design changes.

8. • Proped cantilever beam : This type of beam has
fixed support on one end and support at other
end is provided from downwards.
Eg : Mall , Public buildings elevation.
• Fixed beam: has fixed supports on both ends.
Eg : Classrooms , Rooms of residence.
• Continuous beam : Has continuous supports.
Supports are simply support.
Reinforcement remains same.
Depth , design remains same.

9. Proped cantilever beam
Cantilever beam

10. Continuous beam
Fixed beam

11. • Types of loading:
• Point load or concentrated load :
When a simple load is acted.
When load is acted on point.
• Uniformly distrubuted load:
When is equally distrubuted on beam.
Eg : slab .
• Uniformly varying load :
Load which uniformly varying on straight line.
Eg : 10 kN to 1 kN.

12. Bending moment
• A bending moment is a reaction in an structural
element when an external force is induced on it
causing an element to bend.
• The most common example of bending moment
created in structural element is BEAM.

13. • The example shows a beam which is simply
supported at both ends.
• Simply supported means each of beam can
rotate therefore each end support has no
bending moment.
• The ends can react to shear load.
• The other ends have fixed support thus they
react to both shear force and bending moment.
• Beams also have on end fixed and other rotating.

14. • The simplest type of beam is cantilever.
• The beam which has fixed support at one end
and free at other.
• In reality beams are neither fixed nor absolutely
free.
• The resultant internal couple is called bending
moment whereas internal force is called shear
force.
• The bending moment at section through a
structural element may be defined as “THE SUM
OF MOMENTS ABOUT THAT SECTION OF
ALL EXTERNAL FORCES ACTING ON ONE
SIDE OF THAT SECTION.

15. • If clockwise bending moment is taken negative ,
than a bending moment will cause “SAGGING”
and a positive moment will cause “HOGGING”.
• A point of zero bending moment is a point of
COUTRAFLEXURE – point of transition from
hogging to sagging and vice versa.

16. Calculation
• An important part of determining bending
moment in practical moments of force .
• Let F be a force acting on point A in body .
• The moment of this force about a reference point
is defined as M = r•F.
• Where M is moment and r is reference point to
point of application (A) .

18. • Submitted by:
Galiawala Priyashi (1416)
Jariwala Krushangi (1422)
Jariwala Jinal (1421 )
Jariwala Dipesh (1420)
Kapadia Tejasvini (1427)
Lapsiwala Shivani (1429)
Vana Hussain (14 )