Beam deflection calculation - how to deal with units easily
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- เผยแพร่เมื่อ 10 ก.ย. 2024
- Watch this tutorial on how to calculate deflection in a timber beam.
✅Get the reference tables used in this video: geni.us/timber...
Subscribe to the channel now: www.youtube.com...
It can be really difficult to deal with units when doing a beam deflection calculation, no matter whether it is steel or timber you are working with. So in this short tutorial I explain all the units, and what to do to convert them so that you get an easy to perform calculation with the right output in millimetres.
This video is for entertainment and not to be considered as advice. I am a chartered civil engineer but can't comment on your specific project here. For that I recommend you get in touch with your local chartered civil or structural engineer.
👍 Free download for the tables used in this video: geni.us/timbercalculation
Hey Robin. I think your links are gone dead. Do you have any alternatives for the span tables? Thanks. 👍
Thank you very simply explained including the calculator & units. Thanks so much
Great refresher thank you ( it’s been a loooong time too )
Your can do clear videos will save a lot of people a lot of disappointment and cowboy experiences as well. 👍
Thanks Tim! 👍
Thank you! This was extremely helpful for me. I was trying to calculate deflection in both SI units and Imperial units to be sure they agreed. I had the wrong value for E in SI units.
Great info
Would be good as a final check to just put the all the units into the equation and check they all cancel out to give mm. Great video.
thanks for this. you have simplified all the technicalities. i am trying to build a trailer for a caravan 4.8 x 2.3x2.3 meter (box size) and want to use RHS 100x50@3mm for the main runner . assuming wheels will be on the 2.4 meter mark. how to calculate whether either side can carry 1.5 kpa residential load. what method would confirm?
thanks for nicely explanation.
how to calculate save deflection / max load for whole floor made with wooden joists spaced for about 350mm?
HI, good explanation and good to know just how much work you have to do to calculate this. What audience are you aiming for as I wouldn't want to calculate anything if it was as complicated as that? On-site, I think generally builders/roofers use timbers they're told to use or over-specify. If a builder/roofer changes a timber size, he is redesigning and is not qualified to do so also won't have PI insurance.
Hi Steve - congrats on your great youtube channel! You're correct, this video is mostly aimed at engineers and technicians, as this is quite a complex calculation. Generally I teach a much simpler rule-of-thumb calculation for deflection, and also provide some flat roof span tables here: geni.us/timbercalculation
Hi Robin , could you please tell me at 7:55 mins onward where does this 14mm deflection figure come from ? I understand the rule of thumb
Nice job! For me you should maybe just say what the point load represents.
Can u calculate the cantilever beam
Good job! Could you do a video regarding seismic engineering design?
I’m not an engineer but i enjoy practical maths. Why wasn’t maths taught in context at school?
Hi Mo. I agree. It wasn't until I started using maths to calculate beams and trusses (structural mechanics) that I started enjoying it. Same with working out compound interest for mortgages, and predicting statistical outcomes - the application is what makes the learning interesting!
I have a old oak beam of 5000 length, 278mm height and 200mm width it is close to 200 years old, so would this be a THA grade? But I'm struggling to find the EI for this type of beam I think it is 15961 and 153? Great video!
Hi. With timber grade, be aware that BS uses a "permissible stress" grade that already includes a safety factor, whereas Eurocode uses "limit state" design where the safety factor is on the loadings. So you will get vastly differing values when you search online. The method I teach uses British Standards, so you might go with D40 Oak.
Just kN and cm much smaler numbers...
1 x 300³ / (48 x 720 x 3.333) x kN x cm ³/ (kN/cm² x cm^4) = 0,234 cm
Length x 100
N/mm² => / 10 = kN/cm²
point load => already in kN
line load kN/m => /100 => kN/cm
Hi Robin. Great simple explanation, but it's a shame your final calculation is hidden by the crop at the bottom of the screen. I'd suggest getting a higher resolution camera like 4K and then cropping in post (Divinci Resolve comes highly recommended, because it's not only very powerful, but also free), so you zoom out a bit and don't have to keep remembering to slide the paper up to fit the frame.
Thanks for the advice Tom! 👍 The blue pop-up has the information in it that was hidden, so you haven't missed anything.
Using metrics is very cumbersome for Americans carpenters who use 2x8's,feet,pounds and inches.
Metric system is the best.