Shear Force & Bending Moment



Shear Force & Bending Moment
Shear  Force: It is the force acting on a body in Opposite Directions. In Shear Force, One part of the body is pushed in One direction & other part of the same body is pushed in Opposite direction.


A Beam is normally Horizontal in direction & Loads acting on the beams are in  Vertical direction

The  Following are the important types of Loads
(I)    Point Load
(II)  Uniform distributed load (UDL)
(III) Uniformly Varying load 


1) Point Loads or Concentrated Loads:


  A point Load is one , in which the load is consider to act in a Particular Point or a concentrated point.   
Although in practice it must be distributed over a small area.


2) Uniformly Distributed Load (UDL)



     A Uniformly Distributed Load is one, in which the Load is distributed equally over a beam. In such a manner that, rate of loading (W) is uniform along the length. Each unit length is loaded with the same rate of weight.

==>  the rate of loading is expressed as W N/m
==> for solving the numerical problems, the total uniform distributed load is converted  into a point load acting at the center of UDL

3) Uniformly Varying Load

  A Uniformly Varying load is one, in which the load is spread over a beam, where the load is varying from Point to Point  along the beam, as shown in above fig.,
 ==> Here the load is Zero at one end & increases uniformly to the other end. Such load is called Triangular Load.
 ==> for solving the numerical problems, the total Uniformly Varying Load is equal to the area of the triangle. and the total load is assumed to be acting at the Center of Gravity, of the triangle. i.e., at a distance of 2/3rd of the total length of beam from heft hand side.
Sign Conventions for shear force & Bending Moment




Small Problem on Shear Force & Bending Moment




Small Problem on Shear Force & Bending Moment with UDL