1.
Simply Supported Beam
It is one of the simplest structural elements that both ends rest on supports but is
free to rotate. It contains pinned support at one end and a roller support at the other
end. Based on the assigned load, it sustains shearing and bending.
Use:-
A simply supported beam is one that rests on two supports and is free to
move horizontally. Typical practical applications of simply supported beams
with point loadings include bridges, beams in buildings, and beds of
machine tools.bridges, beams in buildings, and beds of machine
tool
Advantages:-
1. It is quick and simple to analyse a simply supported beam.
2. Simply supported beams are quick and simple to install
3. A simply supported beam has no ability to transfer moments at its supports. This
is a big advantage where the supporting member may need to be very slender and
because of this is only capable of carrying axial loads.
4. Simply supported beams require no complicated connection to the supporting
member.
5. Simply supported beams transfer less load into a central supporting member than
a continuous beam.
2. Fixed Beam
It is supported at both ends and fixed to resist rotation. It is also called a built-in
beam. The fixed ends produce moments other than the reactions.
Use:-
Flag staff in an example of a fixed beam. In reality all tall structures are
fixed beams; only the way they are fixed seems different. The world trade
center building that is 110 storeys tall can be considered a fixed beam. This
may not be very apparent due to the presence of intermediate columns and
beams.
Advantages:-
Fixed beams have many advantages over simply supported beams. Here some
advantages are mentioned.
It has more load capacity than the simply supported beam for the same
loading condition.
It has a lesser value of maximum deflection than that for a simply supported
beam.
It is subjected to a lesser maximum bending moment than that for a simply
supported beam.
The slope of fixed beams at both ends is zero.
3. Cantilever Beam
If a beam is fixed at one end and set to be free at the other end, it is termed as a
cantilever beam. The beam distributes the load back to the support where it is
forced against a moment and shear stress. Cantilever beams allow the creation of a
bay window, balconies, and some bridges.
Use:-
In building, any beam built into a wall and with the free end projecting forms
a cantilever. Longer cantilevers are incorporated in a building when clear
space is required below, with the cantilevers carrying a gallery, roof,
canopy, runway for an overhead travelling crane, or part of a building
above.
Advantages:-
1.Cantilever beam is simple in constructions.
2. It does not require a support on the opposite side.
3. Cantilevered structure generates a negative bending moment which counteracts
positive bending moment of back-spans.
4. Cantilevered trusses use less material.
5. It provides greater clear height in the center than can be obtained with any other
types of trusses.
4. Continuous Beam
A continuous beam has more than two supports distributed along its entire length.
Use:-
Continuous beams are commonly used in the construction of bridge
structures. The ability of continuous beams to distribute loads and resist
bending moments makes them ideal for spanning long distances and
supporting heavy loads
Advantages:-
1. They have a higher vertical load capacity.
2. They reduce deflection of the mid-span.
3. They reduce the number of decks and bearings that are required in bridge-
building.
4. They require fewer tendon anchorages.
5. They offer redundant load paths.
6. They strengthen the structure while also minimizing its weight.
