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Hi rothehitman, correct, I have excluded the axial forces in the members and these are required to allow their full design. What I thought would be a quick topic to cover, already stretches over seven videos and so I have omitted this for brevity. The methods to find the axial forces are exactly the same as outlined above for the BMDs: create your FBDs and use statical analysis - Mike

Hi ktkiigen, I have just checked the video and I am pretty sure that the point lies between 0.2 and 0.3. Remember that we are using the curved lines which have their labels ABOVE them. Apologies for the slow response - Mike

Hi keithkagiri1604, good question. You do need distribution steel and I would look at the minimum cross sectional area of steel required for a slab. You would also need to check minimum bar sizes and spacings in relation to cracking. All in all, this really would need a separate video - the alternative would be to speak to an experienced RC detailer who is likely to know this better than the design engineer. Sorry for not directly answering your question - Mike

Hi WG-ft6tz, if I understand you correctly, then you are making good sense to me, Mike

Hi rubatcross6374, good point. This video is only really meant as an introduction to the sizing of the main reinforcement in an RC column. There is a tiny bit of guidance on the spacing of links but there is so much more to cover regarding the minimum provisiona and spacing of all bars within a structural element. You are right, additional bars are needed to complete the full design of the column. It's surprising how little time there is to do things in just 14 minutes, Mike

Hi Alissa, in analysis, we follow some arbitrary conventions to help to keep us sane. In the UK structural engineers draw bending moments on the tension face of beams, whereas mechanical engineers draw them on the compression face. You could consider clockwise moments to be negative or positive. The most important thing you can do when analysing moments is to be consistent and to clearly understand the size of any moments and to understand whether a beam is hogging or sagging. On this basis, I can’t say that you are right or that I am right, I hope that this helps, Mike

Hi georgen9755, ha ha yes, we talk about the buckling resistance of the steel beam as it could fail due to lateral torsional buckling. I know that we really are checking the beam as an element in bending, but without restraint, relatively flimsy steel beams can fail in lateral torsional buckling. Best wishes, Mike

Hi Nvelopmusic, thanks for the comments. In the UK there are two books used by almost all engineers designing connections: The Green Books by the SCI / BCSA. Text books are few and far between. Owens and Cheal wrote a good one a long time ago and more recently a student showed my one by Alfredo Boracchini - I have not read this one. Hope this helps, Mike

@@mikebather I will see if I can find copies of these. Thank you for the info!

Hi Mohab, in a simplified way, the Eurocodes are not used to analyse structures but just to design them (after the analysis is completed). I make use of the IStructE book Manual for the design of reinforced concrete building structures, which gives methods for carrying out the hand analysis of framed structures. There are other books that you can use also. I suspect that these days, most analyses in industry are carried out by computer. Hope that this helps, Mike these days

Hi kasturchakraborty, thanks for the comment and good question. In reality, most Vierendeel girders may well have UDLs and/or point loads applied to their top or bottom chords but we can model them as a series of point loads (applied to either top or bottom); this is OK, at preliminary modelling stage, we are just getting a feel for the structure and so we have to simplify it (as long as we realise that the final reality will be different - but we can fine tune our structure at a later date). I hope this helps, Mike

@@mikebather Thank you so much for your response.

Hi Max Mooney, at this point, you are calculating the force in each bolt. So, there are two bolts at the top of the connection and each of these carries a tension force of 62.2 kN. Best wishes, Mike

Hello. How to calculate the area of reinnforcement without using graf? There is a empirical formulas to calculate As without graf and using N/b*h*fck, M/b*h^2*fck and d/h? Thanks

@@inzhener-konstruktor This equation is based on strain-stress relationship and doesn't require any graphs.

@@stefanstoichev8108 Thanks for the answer. But I need formula, based on this graphs of the example in this video, do you now this formulas? Not to look at the graph but to determine this value by the formula. Thanks

@@inzhener-konstruktor This are called the "normalised axial force and normalised bending moment". You use them to find you place in the graph. There are around 20-30 graphs, depending on your steel class, concrete class and d2/h ratio.

@@stefanstoichev8108 "In your example I get around 1000 mm2 per side, or 2000 mm2 for the whole section, wich is As.fyk / (b.h.fck) = 0.22" Write me please fcd? fyk? can you write this values that you use in your equation?

Hi sid j, that is a good question. I needed to keep the length of the video short for YT. You are right, what is proposed is conservative but, where shear is relatively small (around mid-span) we should check to see if we could reduce shear reinforcement to the minimum. This gives the designer a little extra work but reduces materials and so reduces the carbon footprint. Thanks, Mike