Steps for Modifying the Beam
- Cut the web area of the beam in a zigzag way through out its length, like shown in the picture below:
The above picture is showing the side view of the I-beam and the red line indicating the line you have to cut (slit) the beam. So, you will get two pieces of the beam after cutting it.
2. Now, you have to weld at the crests of the two pieces. After the welding is done it will look like below:
Please observe that the overall height of the beam is increased after you weld it.
3. Cut the extra projected portions of both the halves of the beam and give it a good looking form like below:
4. The modified I-beam is ready for your structural use now.
5. You might be wondering, how you will get additional strength from this modified beam, to answer your query let’s go to the basic beam deflection equation:
f is the bending stress
M - the moment at the neutral axis
y - the perpendicular distance to the neutral axis
I - the area moment of inertia about the neutral axis.
Now, as you have already observed that in the process of cutting and welding the I-beam, the overall height of the beam has been increased and, as the height of the beam increased, the area moment of inertia of the beam is also increased. Thus, from the eqn.1 you can draw the conclusion that the developed bending stress value (f) will decrease with increasing height of the beam, or in other words, the strength of the beam will increase.