Concept of Practical Beam | Report

Practical Beam 20 March 2020
Content
Introduction................................................................................................
............2
Aim.........................................................................................................
..................2
Material
Used.........................................................................................................2
Design and
Construction.......................................................................................2
Working
Principle...................................................................................................2
Observation and
Discussion.................................................................................3
Conclusion...................................................................................................
............3
1

Practical Beam 20 March 2020
Introduction
This beam practical introduces the principles of building beams with some different
structures and designs so that we will get to know about some of the best design in the real
world.
2

Practical Beam 20 March 2020
Aim
The main aim of this practice is to remark the failure of different beams and determine the
strongest beam from all those constructed beams. Basically, we checked the weight holding
capacity of every beam by putting a load until the beam failed. By doing this we got fine
design at the end.
Material Used
 Balsa wood (1.55mm x 70 mm x 915mm)
 Super Glue
 Cutter
Design and Construction
With the Balsa wood (1.55mm x 70 mm x 915mm) we had to make beams with the different
design and structures. The concept of making this beam was to come with different ideas so
that we can differently design with different dimensions. Each beam was built longer than
550 mm so that beam would span on 550mm and it was in rectangular cross-section and after
a week it was tested to carry the maximum possible load.
Working principle
A beam works on the principle of moments. Beams hold the load by bending only. Due to
moment, it causes an internal shear force that passes on the same force on beam support.
Shear forces develop diagonal tensile and compressive stress.
3

Practical Beam 20 March 2020
Since balsa wood has better tensile strength than compressive strength so strain distribution
will be equal to stress distribution.
One method is to make a strong beam by using strong material. Alternatively, its strength
depends on the moment of resistance:
M=kbh²σmax (for rectangular cross-section beams)
In the above-mentioned equation, the moment varies directly with the width of cross-section
and with the square of the depth. So, by increasing the depth of a given cross-section beam,
we can make strong beams which can carry a larger load.
Discussion
The beam structures are as follows:
Precast concrete beam- this type of beam is of high quality and is usually built in a number of
cross-sectional shapes such as T-beam as illustrated below:
Figure: Structure of the precast concrete beam.
Deep beams- this type of beam has large depths with the load usually pulled by the force of
compression. The structure is shown below:
4