Amazing vids! Im in my third year and doing steel structures at the moment. Will be doing Timber Structures and Pile Foundations next semester as well !
haha Exams..fun times hey..I guess you will have to go through all the calcs that the tables provide us. Good luck there mate..let me know how you go. Cheers
Do you precamber steel beams to compensate for short and long term deflection? The PFC would have some restrant due to the joist connection plates that are welded to the flanges and web of the beam at 450 centres. Are you familiar with the publication called Steel Designers Handbook written by Ron Tinyou. He is a structural Engineering lecturer at UTS.
In simple terms, ULS is for the collapse of the structure, reason why the safety factors are higher. SLS is for deflection, vibration, etc which won't cause any collapse of the structure (excessive deflection or vibration is still considered as a failure though). Does that make sense?
@@bengthebrazilianengineerinAus Thanks for your quick reply, I can understand that the deflection and bending moment are linked to each other. The structure deflects more, and we can assume that it is subjected to more bending. Can I understand your explanation like this? Suppose, we check BM and DF under ULS with the same loading factors and material factors. Can we assume that the structure would fail in bending before it reaches the maximum deflection? Therefore, the BM and SF are considered critical and checked under ULS, and the deflection is less critical and, hence, is under SLS.
Sorry to be a pain, i am having trouble repeating your dynamic deflection calc and obtaining the value for Ireq you got. What is the LHS value on the equation presented so we can solve for Ireq? Thank you
Great video. thank you! i wanted to ask is there a standard document/book which shows the weight of building materials for Australia that Engineers refer too? this would help with Load takedowns in the real world. Preferably these values are in kn/m2
Hi mate, thanks for your informative video. Just have a question about the dynamic deflection, so could you please give more information or explanation for this point? Is it declared in the AS or somewhere else? I would like to read further about its applicable ranges, such as for other beams (cantiliver, fixed-ends), other usage purposes (residential, office...) or other restraints (full or without restraints). Thanks.
Hi Dao..this rule comes from the timber code (As1720 if I can remember correctly). It's widely adopted for resi and some commercial projects. Have a look there and let me know if you can't find it and I'll look it up. Cheers
@@bengthebrazilianengineerinAus Thanks mate. It was limited to 2mm in CL4.1.3.5 AS1720.3 for timber joist, but not commonly for timber bearers or especially for steel bearers. I think it should be too conservative when considering serviceability deflection of 1mm for 6m span steel beam in residential buildings. However, the information in your video is valuable. I am looking forward for more videos from you. It is appreciated if you can make more further discussions on the restraints of segment/subsegment from some practical projects you did. Cheers.
@@daohoanghiepphan5138 This number is a rule of thumb for solid sections. As you may have seen on the code, it can vary for different shapes such as I-beams and PFC's. It's primarily for joists, but in some cases you may have to consider dynamics for bearers, such as in long light beams. Try designing a 6m long beam with a big floor load on it and the same beam with a way smaller floor load on it. You will notice that dynamic deflection for the latter is considerably higher. I would look at this problem with the following concept: F=m x a The force is the person walking on the floor. The mass is the weight of the beam. The lighter the beam, the higher is the acceleration, therefore more bounciness. You can calculate the frequency if you're really worried about dynamics as well. For joists, 1.5 is good number.
Hi you hnave not taken the load of steel joist on steel beam in load calculation. These Jiost will apparently act as a point load on the main steel beam.
Hi Hamid, the loads of the joists are included in the dead load. You can simplify it by assuming the various point loads along the beam as a line load.
