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WisconsinEngineerUWP
Registrace 19. 11. 2011
Structural Live Loads
How to calculate live loads on a floor beam, including live load reduction.
zhlédnutí: 1 603
Video
Structural Dead Loads
zhlédnutí 195Před 2 lety
How dead loads are calculated with a short example for a reinforced concrete floor poured on steel decking.
AISC Column Capacity vs Theoretical Capacity
zhlédnutí 807Před 6 lety
Explains the difference between the AISC Column Capacity (Section E3 in the specification) and the theoretical capacity. This work is licensed under a Creative Commons Attribution 4.0 International License. creativecommons.org/licenses/by/4.0/
Using VisualAnalysis to Check a Reinforced Concrete Beam Design
zhlédnutí 1,1KPřed 8 lety
Shows how to use VisualAnalysis (Educational Version) to check a reinforced beam design.
Natural Frequencies of a Building using Mathcad
zhlédnutí 9KPřed 10 lety
Shows how to numerically find the natural frequencies of a building using Mathcad. This is a very simple analysis assuming only one degree of freedom at each story level.
Natural Frequencies of a Building
zhlédnutí 13KPřed 10 lety
A simple demonstration of how to use the matrix equations of motion to find the natural frequencies and mode shapes of a building.
Modal analysis using RISA 2D (Part I)
zhlédnutí 5KPřed 10 lety
The first of two parts on how to use RISA 2D to do a simple modal analysis.
Modal analysis using RISA 2D (Part II)
zhlédnutí 1,3KPřed 10 lety
How to do modal analysis using an older version of RISA 2D.
Reinforced Concrete Beam Shear Failure
zhlédnutí 119KPřed 10 lety
Showing the failure of a small reinforced concrete beam. The load was designed to show a shear failure. Date: December 7, 2012
Using Table 6-1 of the Steel Manual
zhlédnutí 21KPřed 10 lety
An example beam-column analysis problem using Table 6-1 from the 14th Edition of the AISC Manual of Steel Construction (and older).
RISA Frame Analysis Tutorial
zhlédnutí 27KPřed 11 lety
A short tutorial on using RISA-2D to analyze moment and braced frames to determine the lateral deflection.
The Citicorp Building
zhlédnutí 12KPřed 12 lety
In 1978, structural engineer William LeMessurier determined that a construction change for he Citicorp building had potentially resulted in a structure that was structurally unsound. Disclaimer: This is a student-produced video. The information has not been independently verified and should not be used without further verification.
Bolted and Welded Connections
zhlédnutí 7KPřed 12 lety
Overview of the advantages of steel construction with information on how connections are constructed. Disclaimer: This is a student-produced video. The information has not been independently verified and should not be used without further verification.
Heat Straightening
zhlédnutí 75KPřed 12 lety
A method to bridge beams that can be more economical than replacement. Disclaimer: This is a student-produced video. The information has not been independently verified and should not be used without further verification.
Structural Health Monitoring of Steel
zhlédnutí 1,1KPřed 12 lety
Overview of how sensors can be used to monitor stresses and strains in structures to detect structural problems before they occur. Disclaimer: This is a student-produced video. The information has not been independently verified and should not be used without further verification.
Northridge Earthquake: Changes in Moment Connection Design and Verification
zhlédnutí 8KPřed 12 lety
Northridge Earthquake: Changes in Moment Connection Design and Verification
Do these tables not exist in the 15th ed? Or just moved?
40 years later and people are STILL joking about this damn bridge's name.
Those walkways were very weak amazing they lasted for that long
I wish my Professor taught us this method. I'm sure he had his reasons, but I'm glad I came across this. Thank you so much!
Steel reinforcement be like : your welcome
About a year before this happened I used drive this section of I-95. When driving this section I heard a very strange humming/ vibration type sound I've never heard since then. Guess it was not my time.
I can't believe this video has no comments. I used to work in a oil field drilling rig manufacturing facility and we use this to heat process to straighten beams before we built the pits and any other kind of structure that needed to be straight.
Problem was found once the building was already occupied and not during construction.
Thanks!! Prefect video. This will help me for my PE
This is awesome. Definitely going to use this on my upcoming SE Exam.
Apparently this was meant to be a very brief summary. However, since the main point centered on the change from LeMessurier's Welded to the actual Bolted beam assembly of building - then *why* would the solution (in this presentation) use the word: APPLIED regarding the solution as "two inch thick plates" to 200 bolted joints. 'APPLIED how?' by bolting or wielding? is the obvious question immediately asked by the interested viewer.
Lazy contractor mentality " impossible to construct" and revise / propose their own method....most contractors are constructor only and are not experienced structural designer.
the NIST recently reevaluated the wind loads on the building's structure - and concluded that the wind loads were not the threat LeMessurier thought - maybe the original structure was safe - (i don't know what they'll say 40 years from now)
Fascinating. Thank you for posting.
i dont find website to answer
Interesante! Dejo link czcams.com/video/9tfGj86YNi0/video.html
wow , well grounded sir
There was a lot of destruction in Mianus.
Lucky for everyone Dianne Hartley asked a simple question why were calculations different from that on the plan. That then started a chain of events which led to the fixing of the building
czcams.com/video/9tfGj86YNi0/video.html
Hartley did express concern about the quartering winds in conversation with an project engineer (not LeMessurier) and in her thesis published April 1978 - however LeMessurier didn't recalculate until June 1978 after a phone call with another student Lee DeCarolis - his recalcs led him to the same conclusion (but differing in details) - however - they might have both been wrong according to a recent NIST study
very strong steel bar used and concrete is elastic in nature . after this much bending beam does not destroy. wow
Thanks You! Excelent explain!
What was the force / pressure at which the beam broke?
Hello again.. i have asked the same doubt in your previous video, i am asking again... I have made a physical model of the same frame that you have considered in the video.. Mass of each storey equal so is stiffness. My main question is, while calculating lateral stiffness of each floor or storey, u considered 24EI/L^3 since there are 2 columns (and 2D figure), but in actual 3D model it would have 4 Columns so should i still consider 24EI/L^3 or go for 48EI/L^3?? would really appreciate your assistance...
No, you are using 2 columns in calculation because you're calculating natural frequencies of one row (column, floor)
@@Lado93 thanks for the help... I have practically calculated natural frequency as well with the help of an accelerometer and compared with theoretical one like in this video.... By considering 2 columns in calculation i found the ans similar to the one i calculated from accelerometer... By considering 4 columns the ans came double 😂
i have one doubt tho.. for such a frame structure as u are considering, the stiffness value of 1 storey should be 24EI/L^3 (Two columns) or 48EI/L^3 (Four Columns)???? hope to hear from you soon. Would really like your help on this...
Well I can answer for that question. I can tell that stiffness of the column in this example is 12EI/L^3. However, because each floor has 2 columns you have to multiple by number of columns and it becomes 24EI/L^3. If you have 4 columns then then it will be 4x12EI/L^3. I hope it helps.
@@dachikhutsi2793 well see the thing is when i determined the natural frequency practically or experimentally watevr u call it, i got answer as 25 rad/s.... now i want to verify this value by solving it theoretically by means of equation of motion as shown in video... I have prepared the equation, all i have to do is enter the values... I tried 4 column concept i got ans as 41.4 rad/s.. but when i considered 2 columns i got ans as 27 rad/s which is really close to the one i got practically... So the question arises that while solving theoretically we always consider 2 columns for such frame cases?? Is it a thing that while solving eq of motion, one hasbto consider 2D figure instead of 3D figure??Btw thanks for the reply 👍👍
@@kevinwadia3325 do you use what's app or anything? I would love to help and I know the answer to your question but I need to explain it to you
@@kevinwadia3325 you probably have pinned support connection where you have to use k= 3EI/L^3
@@dachikhutsi2793 sry i dosed off... It was 3:30AM so 😂😂.... Well its a simple CPVC physical model and all of the joints are fixed...
Wrongly labeled. Design was not engineered for quartering winds..
the design included quartering winds - there are engineers who did those studies who have spoken up - however after speaking with student Lee Carolis - the chief engineer Wm LeMessurier later recalculated the wind loads and grew concerned - however it seems his concern (and Diane Hartley's who wrote a thesis expressing concern over the quartering wind load) was unfounded - the NIST has reassessed the wind loads and says the quartering winds WERE NOT the threat that those two thought - suggesting that the building did not need to be reinforced
Diane Lee Hartley
Maybe. Her story is very corroborated but LeMessurier said he talked to male student. And, LeMessurier certainly seems like a man that would give proper credit. Entirely possible that multiple students flagged the problem.
@@thomasarcturus8947 - that male student is Lee DeCarolis - but he didn't flag the problem - he just got LeMussurier to rethink the wind loads - the capper to this story however is the recent NIST reassessment of the building - and their finding that the ORIGINAL design was strong enuf - no danger existed
Really instructional video. I wish you could do more steel design videos.
I still do not trust this building. it does not look stable. I would like to see some computer modeling under various wind load conditions. RIP to all when it finally comes down.
your command is NIST's wish - they recently concluded that the wind loads were not the threat LeMessurier thought - maybe the original structure was safe - now it's even stronger due to the reinforcement made in the latter part of 1978
helpful indeed, but could you please upload a lecture on design of members in compression , tension, bending and bi axial bending and compression (combined). i am asking for the whole steel design.`
Hi, I don't think your matrices are correct. Orthogonally you matrices should be 2, 2, 1 because one end is fixed and another end is free, thus you should have k1+k2, k2+k3, k3
He has rectified that in his next video where he solves the same case by Mathcab
How do i define de matrix k?
Very helpful example no need to explain any way thanks
Thank you for your thorough explanation, very helpful! I am using MATLAB and I'm sure it is pretty much the same thing as mathcad, could you also update the code used for this video? That would be great
can we use table 6-1 for plate girder ??
No, Table 6-1 is for standard W-shapes. Table 6-1 is also not available in the new manual, which now has a "super table" that you can use to find the factored design capacity for each limit state directly.
Great video! gladly to be your 1000 subscriber :D
This looks like a flexural failure first... perhaps you should have designed the beam without stirrups and cross steel if you wanted shear failure first... Down size the steel or change dimensions of beam... or even bring load point in closer... Just looks like flexural failure first and of course shear may happen afterwards or it can just fail at the flexural failure and no shear can be clearly shown...
How to solve 6*6 matrices to find eigenvalues in mathcad???
The process is exactly the same, just use 6x6 matrices for your mass and stiffness matrices. All other syntax is the same and you will get all six frequencies and mode shapes at once.
@@WisconsinEngineerUWP thank you Sir.
Your 3:40 min video helped me as a 2-3 hours seminar! Thank you!
thank you! very great help!
They started as flexural cracks and once shear was higher than let’s say 3.5sqrt of f’c transition to tension cracks
Nicely explained.
I wish I had a professor like him
Sir how can be solve 6× 6 matrix. Of stiffness and mass matrix in excel for mode shape
Thank u sir👍
When concrete breaks do the rocks usually shear with the crack or just pull out.....looking at the bridge in florida i have never seen rocks shear so clean..like the were using soft rocks..??
I was standing on a thin (to me) concrete platform and remarked to an accompanying friend, "I just cant see how this is strong." I can see how it's strong now. Good job, boffins.
They never should what was the size of the rebar and what was the pressure
SHUTTERING FAILURE czcams.com/video/iVddJWB9rXs/video.html
This is a really informative visual example of flexural and shear failure..helped me in my project =)
Hydraulic press vs concrete beam
can i get this slide?
there is no shear or flexural failure both are principal stress failure in tension where principal stresses are in angle close to supports. Crack is always perpendicular to tensile stress. In short beams support region is problematic in long beams mid cross section is problematic. I am just typing this because people sometimes dont realize its more about principal stress trajectories than strictly trying to isolate shear and flex