How to do a steel beam deflection calculation

Here's how to calculate the amount of deflection in a steel beam. After calculating your steel beam's strength, you need to do a steel beam deflection calculation to check if it will deflect more than the allowable amount. Even if your beam is strong enough, it may still deflect too much! In this easy-to-follow tutorial, we take you to step by step through a worked example, explaining the formula and values so that you can easily carry out your steel beam deflection calculations.

[Iffy]

This is a great video. I calculated deflection last week at work and I compared my answer in SI and Imperial units to be sure they matched. They did not. I switched from meters to mm and the Young's Modulus used here and everything worked out.

[dragosionutbratosin]

the right answer is 12.205mm, because the second moment for the UB in the example 25500 cm4

[pogarda]

from the Structural engineer's pocket book third edition, the second moment of area UB 457x152x60 is 25500cm^4, it can't be 21.5x10^7

[samirel-nagi]

Hi
Thank you for these informative, refreshing structural analysis videos. It will be much appreciated if you cover analysis of masonry walls with one and two openings subject to lateral wind loads. Please try to cover most scenarios.

[chitpaul]

Start from where you got the imposed load from, 4.9kN/m .?

[sudhakarpersonal]

Hello for steel beam, Rafters, and columns all deflection check is span/360. Or it will change. Please let me know.

[arvindpatil]

Thank you so much this
Just wanted to know, at last the length was divided by 360 to check whether the deformation is acceptable or not
What is 360 ??
Is it standard value to be considered while accepting the deformation?

[sandiwijaya]

1:46 hello, the "60" how it come from? thanks

[rockervipro]

Nice video thanks! From the table of properties I get a second moment of area (257x152x60) of 25.72 x 10^7 mm4. In your video you seem to have used the one of (257x152x52) which is 21.59 x 10^7. Could you review this?

[emmadavies]

Interesting and very useful to know thank you 😊

[bart]

Can you calculate the defelction on 2, 5 m from the left side? How?

[JPcostarica]

Where span/360 came from? Is that a formula for maximun accepted deflection no matter beam type, just considering the lenght?

[GaloAalo]

Why load 4.9 is not multiply with factor load?

[oseghaleengineer]

Interesting! Appreciated. Pls how do you get the beam member sizing supporting a slab load over a span of 17m? I mean the classification of I-beam for such span?

[kyleharris]

The million dollar question is how did you get the second moment of area as 21500cm4 and in the design tables it is clearly 25500cm4 for a 457 x 152 x 60

[MrMuhammadhafizuddin]

I got the answer is 1.447mm...please correct me if i wrong....one more question, can i use this formula to calculation Square Hollow Section?

[Irishfan]

I would have preferred to see this in US Standard units instead of metric.

[wafikhwijeh]

Please.. How could you calculate I for I beam section? I know the equation of it is b*h3/12 ?

[akashsorathiya]

why we neglected self weight of beam
????

[AMJB]

I reckon it would be less deflection in the real world 27mm seems like alot