colincaprani.com

Comment from Chris Powell-Williams
Time: 22 June, 2008, 01:27

Dear Sir

I believe there is an error in your lecture notes on Mohr’s Theorems concerning the deflection of a cantilever under a point load at the tip (Example 2 in lecture notes). The expression should read δ(b) = PL^3/3EI .
Also the rotation @ B should read tan (ϕ(b)) = PL^2/2EI then by the small angle approximation tan (ϕ) ~ ϕ hence small tip deflection (relative to the section bending area) and then you can use your approximation that the arc length & chord length are approximately equal.

Also have you ever looked at the membrane equations for the hoop and meridional stresses in a segment of a hemispherical dome under its self weight? if the angle ϕ is defined as zero at the crown hence hoop stress is zero (meridional stress stays compressive within the quadrant), at an angle 51.82…° (cos[ϕ]=(1/2)(SQRT(5) -1) this is the golden ratio & allows for a minimum weight design for the shell as it can best utilise the properties of most materials (bar rubber & the like !). Just thought that would be interesting for your section of the roll of engineering within architecture.

Hope these ideas can be of some use.

Chris Powell-Williams

Comment from Colin
Time: 28 June, 2008, 14:16

Chris,
Thanks for taking the time to post. The PL^2 att he bottom of page 10 should indeed be a PL^3 as may be verified by multiplication of the previous line. Typos like this inevitably creep into notes – thanks for helping getting rid of one!
Regarding the calculation of the rotation at B – since the approximation of arc and chord length is inherent in the development of Mohr’s First Theorem (p. 5), we can directly say that for small deformations, ϕ(b) = PL^2/2EI directly, without needing to invoke the small angle approximation, tan (ϕ) ~ ϕ. Though, of course, mathematically this is fine to do.
Lastly, I appreciate your comments on shell stresses. This is definately an intersting area, though there hasn’t been time on my various courses to lecture on shells. Perhaps this will change!
Thanks again,
Colin

Comment from Messaoud
Time: 10 July, 2008, 17:25

Excellent set of notes!

Comment from Colin
Time: 16 July, 2008, 00:53

Thanks Messaoud!

Comment from MAMUYE
Time: 7 August, 2008, 15:20

Your material is good and so much supportive for developing countries Universities.
Thankyou!

Comment from Dr. Subba Rao.P
Time: 8 September, 2008, 13:39

Dear sir, your efforts are realy appriciatable and useful both teachers and students as well. Regarding comments on notes, I have to yet to go through.

Comment from Neil Kempton
Time: 24 October, 2008, 15:38

An excellent set of notes. Very impressive!

Comment from Cathy
Time: 2 December, 2008, 20:21

Colin,
I just have to comment on your set of notes and your website in general. I must admit, I have only viewed your website for the first time today even though you advised us to view it at the start of the year (i`m in your Tuesday afternoon lecture ). After seeing what information and knowledge there is to offer here, for present and future study, I will be reccomending this site as a must view to all my college friends.
I also looked your theses on timber connections for cable-stayed bridges, which you wrote when you were taking the course I am currently doing(?)I think, and i was shamed by the work and effort I have been putting into mine in comparison to yours.
If I become half as knowledgable in structures as you, I will be a very successful engineer. And I will try my best to avoid the Third Year Syndrome!

Comment from Conor Hayes
Time: 15 February, 2009, 23:03

While googling something about punching shear I came across some lecture notes of yours on the subject. In the text you state that ‘the failure is due to shear’. My understanding is that the failure is due to a combination of shear and bending moment, and that this is what differentiates punching shear from plane shear. The design values of shear used in punching shear checks under both BS8110 and EC2 seems to be increased to take account of the BM transferred from the slab into the column.

Am I mistaken on this? I am not writing to be ‘smart’ but because I am interested and because I thought the explanation was a bit misleading.

Thanks

Conor

Comment from Colin
Time: 16 February, 2009, 03:37

Conor,
Thanks for posting your comments. It’s been a while since I have worked closely with either code and so can’t really comment on their specifics with any great degree of knowledge. Since shear is the rate of change of bending moment, and since bending moment changes over a column head, I would not be suprised to find a bending moment term in an expression for punching shear. This would of course be in addition to the primary source of shear stress from the column reaction to the slab loading. Thus I argue that bending moment does not cause punching shear directly and that it is the shear forces which come from two (or more) sources. Of course, since shear is really just another word for tension and compression at different angles (Mohr’s Circle), you could just argue that tensile stresses cause punching shear failures and I don’t think many would contradict you.
I’m sure your reading of the codes is fine, but before applying their rules I prefer to get to the underlying physics of the problem and understand it (as much as I can) since codes will change as understanding improves. Let me know if that helps any.

Comment from Keke
Time: 5 May, 2009, 17:51

I found your notes very informative. I am a civil engineering student in South Africa and would sometimes need help. would you mind assisting me?

Comment from Colin
Time: 6 May, 2009, 00:30

Keke,
I’m glad you find the notes useful but that is as mush assistance as I can offer you. Good luck with your studies.

Comment from Michael
Time: 29 June, 2009, 00:33

Fantastic resource! I have book marked this to explore all of it in due time. I was interested in your notes under the “Architecture” section but the links seem to be dead. Have they been posted somewhere else? Please help if you are able.

Comment from Aji Ardhiansyah
Time: 7 August, 2009, 17:28

Dear Prof,
There a lot of course in your site. Thank in advance

Comment from Bill
Time: 18 August, 2009, 15:38

First of all, I’d like to commend you on this website. I am a UCD graduate of Civil Engineering this year 2009 and have to say I used it quite a bit when I found it. There are very few resources for current issues in irish structural engineering-none better than this for evoking my interest anyway. I hope you keep up your enthusiasm for transferring knowledge in such an easily accessible way.

Comment from pav
Time: 1 October, 2009, 06:49

Basically i’m a mechanical engineer. i’m doing a job in construction field, while going through different sites to pass the time i got this site and i stuck up with it. i don’t know how its gona help me but it is a gift to civil engineer students.

Comment from Atakalti
Time: 18 March, 2010, 08:41

Hi peace for you

Comment from alehegn yehuala
Time: 29 April, 2010, 13:07

i am acivil engineering student in jimma university . and because in our country ethiopia there is no usefull books in our department itis very essential for me and my freinds to read courses . thank u!!!.bythe way when i see the first timt your name seems as acompany name for me because ,many things ihaveseen it that i lost from other web sites . finally if u have time please send books or other reading materials for foundation engineering course bybybyby see you later. i wish to u best things for u needs !!!!!

Comment from Engr OKELAWO INNOCENT USMAN
Time: 31 May, 2010, 18:12

today is my first time of spending virtually the whole day on the net. iam a senior lecturer at the only institution offering building and civil engineering upto a degree level in the republic of the Gambia. to be precise, i must say that i really thank those who have in way or the other contributed to all the lecture note i have read and infact i must confess that they have made it so easy for lecturers like us in africa who can not afford the expencive testbooks. once again i thank you all. from shaykh mahfous institute of professional studies.

Comment from A S PATHADE
Time: 23 September, 2010, 18:52

Sir, the notes are extraordinary and extremely useful, especially structural dynamics ones. Thank you so much.

Comment from Hemant S
Time: 29 September, 2010, 06:22

Sir the site is really wonderfull having lot of useful information the material is very very good.
Thank you Sir for this site

Comment from Sarah
Time: 12 October, 2010, 18:45

Dear Dr. Caprani,
I am inquiring as to whether the notes on Structural Scheme Design (UCD/DIT) are still available as the link does not appear to work.

Regards,

Sarah

Comment from Rob
Time: 30 October, 2010, 00:51

Its really excellent you make the notes available for anyone to download like khanacademy.com. What would be a noble cause is if lecturers from all colleges amalgamated their notes together and produced them online so that education in Ireland from university to university basis would be transparent. I wonder what is the reason that this hasn’t been done.

Comment from Koos
Time: 5 January, 2011, 11:45

Aweh hond! This site is befokd! Thanks hond!
I can steek structures now at UCT!!

Comment from Alex
Time: 3 November, 2011, 23:55

Dear Colin, for the past two years, I have been reading your notes and it has been very helpful to my first BA in civil engineering.And, I am still using it to my graduate classes. you have the most completed notes i ever had before and it had been very helpful for me. I thank you so much and i wish you to do more and more to years to come.

Comment from benjamin lawortey
Time: 12 November, 2011, 14:49

please can i get lecture notes on structural design for 4th year student?

Comment from Admin
Time: 13 November, 2011, 03:56

Feel free to download whatever is relevant to you, but I cannot provide notes I don’t have. If you find a good website would you mind posting it here for others please?

Comment from Jing
Time: 31 January, 2012, 07:43

Dear Sir,

Do you have any worked examples to prestressed concrete design based on BS 8110?

Comment from Admin
Time: 31 January, 2012, 21:57

Some examples are in the notes on these pages. If it is not here I don’t have it. Good luck!

Comment from Stuart Earl
Time: 7 February, 2012, 13:19

Hi I would just like to add to the list of thanks present in your comments section.
I cannot overstate just how useful your notes are, especially concerning the plastic analysis of frames and YLA for my 4th year here at Dundee University.
As you know there are many textbooks on such topics yet still your freely accessible notes are the go to source for understanding these topics.
Making notes like this free to use for students such as myself is an incredible moral decision given that, I would imagine you could stand to profit with such a high quality website.
I would imagine you have been instrumental in helping students of all backgrounds achieve a high standard of degree!

Keep up the good work!

Comment from Admin
Time: 8 February, 2012, 18:38

Stuart,
Thank you for taking the time to comment. Thank you also for your kind and encouraging comments – it really does make it worthwhile to share the information when I hear of students that are helped. I am really passionate about structural engineering and am just trying to spread the word and help others find the same delight in it as I do.

Best of luck with your studies and future career,

Colin

Comment from kuttan
Time: 26 February, 2012, 10:47

This is a very very good site

Comment from Nkosiphile Dube
Time: 26 March, 2012, 17:36

Thank you very much Dr,these notes have come in very handy.lm veyr grateful.

Comment from Kohki
Time: 6 July, 2012, 17:44

Dear Dr,
I am the PE of Japan and just started to work in Singapore.
I found your site when looking for some help on BS and Eurocode.
This is very helpful for the novice like me at using these codes even though that’s prepared for students.
Thanks for your passion and hope it remains the same for long!!
Kohki

Comment from Admin
Time: 13 August, 2012, 13:18

Kohki,
Thank you for taking the time to post your kind comment. I am glad that the information is finding good use even beyond students. We should never stop learning!
Colin

Comment from Man Mendoza
Time: 5 September, 2012, 13:00

Dear Dr Colin,
I’ve been following your page for months now and I would like to thank you for sharing your ideas to us and providing simple and effective ways to understand some useful concepts and theories in structural engineering. I just want to ask about your answer in Prob 2.6 under Structural Dynamics lecture, my answer is 22.5mm compared to your 28.1mm can you confirm or provide the solution for me if my answer is incorrect?

Kind regards,

Mac

Comment from farah
Time: 19 September, 2012, 04:22

Dear Sir,
I am a lecturer in Malaysia teaching structural subjects. I found your site when looking for some notes on qualitative analysis.
This is very helpful and i extend your site link to my students.
thank you very much for sharing.

Comment from Jan Reyneke
Time: 16 October, 2012, 12:36

Can you help me solve this formula in your prestress conrete. For some reason I dont get to your answer? Maybe you can put the steps in before the final answer. Bottom fiber to calculate minimum section modulus.
Ms/Zb -α Mt/Zb ≥ ƒst – αƒtc. From here you get an answer of Zb ≥ Ms – αMt / ƒsc – αƒtt. Can you please help?

Comment from Admin
Time: 16 October, 2012, 17:50

Jan,
From p32 I think? Multiply both sides by Zt, then divide both sides by ƒsc – αƒtt. If I’ve understood your problem correctly?
Colin

Comment from Jan Reyneke
Time: 17 October, 2012, 11:19

Colin, Thank you for the reply. When doing that on pg32 I get the same answer as you but the Bottom fibre on pg33 why did the denominator turned around to become (αƒtc – ƒst). If I multiply both sides with Zb and devided both sides with ƒst – αƒtc I dont get the denominator the same as yours.
Thank you

Comment from Admin
Time: 17 October, 2012, 18:39

Jan,
Yes, I see your point, it is more involved than p32. The inequality is reversed and Zb is negative complicating things. Proceed as follows: multiply both sides by Zb – this reverses the inequality since Zb is negative. Now divide both sides by fst-aftc. This again reverses the inequality because it is a negative quantity (fst is negative and so is -aftc). Now you have Zb <= (Ms-aMt)/(fst-aftc). Since Zb must be less negative than the right hand side, we take the absolute values of both sides giving |Zb| >= -(Ms-aMt)/(fst-aftc). I’ve absorbed the negative sign into the denominator to keep the numerators of equations (5) & (6) the same and to keep the denominator positive. I agree that equation (6) should have the absolute sign in there to make this clear. I can recommend this book for more explanation: OBrien et al
Hope this helps,
Colin

Comment from vigneshwaran g
Time: 2 November, 2012, 15:39

i am vigneshwaran g studying structural engineering in Hindustan university at chennai, india.i have in this semester design of composite structure. we dont have proper notes so could u tell which one book is best for d.com.construction for indian code related……….

Comment from Hein
Time: 23 November, 2012, 20:49

Dear Colin,
Thank you very much for the amazing notes. I would like to inform you that the following links are not working.

Structure in Architecture (29 KB)
Precedence (10,700 KB)
Structural Art (7,207 KB)
Architects & Engineers (2,524 KB)
Thanks,
Hein

Comment from Michael Daburn
Time: 1 February, 2013, 17:14

Dear Colin,
I stumbled across this page when looking to research punching shear, particularly for car park design & clicked the link for ‘comprehensive set of notes dealing with the preliminary design of structures’ but unfortunately it does not work. Is there any way that I could obtain a copy please?
Thank you in advance.
Michael

Comment from Admin
Time: 1 February, 2013, 20:18

Michael,
Download the notes on the Project III page.
Hope you find them useful,
Colin

Comment from Michael
Time: 3 February, 2013, 11:37

Hello Colin,
Thank you for your very quick response. I have found the notes & they will indeed be useful.
I did see that in your punching shear webpage you mention ‘refer to page 43 of the Quantitative Design Notes’.
Can you tell me if they are on this website?
Many thanks.
Michael

Comment from Admin
Time: 3 February, 2013, 13:02

See the Flat Slab example on p190 of the Project III notes.
Colin

Comment from Shabz
Time: 16 April, 2013, 17:07

Hello collin , i loved your lecture notes and was wondering if you have a particular solution to the document titled
Reinforced Concrete Columns.. i would be really grateful if you could email them to me.

thank you so much.

Comment from Kevin
Time: 1 June, 2013, 22:25

Dear Colin,

Thank you very much for the amazing notes. It seems that the following links are not working.

Structure in Architecture
Precedence
Structural Art
Architects & Engineers

Thanks,
Kevin

Comment from Luisa
Time: 20 August, 2014, 16:03

Dear Dr. Caprani,
I’m very grateful that I found your website. Your notes help me a lot with my study and I would like to thank you for sharing your knowledge to the people. Engineering course is a though one, but because of people like you, things makes a bit easier.

I’m wondering if you have a notes / lecture about Column Analogy Method, I would greatly appreciate if I could have a copy.

Thank you very much! More power to you.