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@@rukhayatorekoya2266 To get the compression index (Cc), that is correct. Project a tangent line from the approximately linear portion of the compression (loading) curve.

@@mathandengineeringwithdr.a9515 thank you

@@IssaAbdulkadir Thank you for your kind words!

Compute the tributary area for each of the columns. Multiply the surface load by the tributary area for a column. This will give you the force that is transferred to a column. Then, this force is transferred to the foundation.

@@mathandengineeringwithdr.a9515 Thanks for the response. Fully agreed in case of buildings etc where live load as occupants and furniture etc would exist at all times in some measure at all levels. Here the live load of maintenance personnel and equipment may exist in some small measure during shutdowns only. The platform is to be designed as per code, rated for this live load of 40psf anywhere where the maintenance work is being done. The platform is never likely to be swamped or infested with men and machinery all over the area, hence considering the total total area multiplied by 40 psf would be overdesign. Kindly let me have your opinion.

Thanks for your question. Chapter 27 would be more appropriate for a monoslope roof for wind loads on the MWFRS. See the user note in 28.1.

@@mathandengineeringwithdr.a9515 Thank you for your reply!

never mind, i found it, i couldnt see it because it was a year old video!

@@user-sk6jq6eh8l Glad you found it! If you navigate from the Mechanics of Materials Playlist, all the videos should be in proper order.

Good day. Thanks for your question. This simply example is just meant to explore how to actually compute a service dead load and then a service live load, that would be used in design. Once we have the dead load and then the live load, we can then use one of the two common structural design philosophies that you mentioned (LRFD or ASD) to get the overall design load.

Thanks for your question. The internal pressure is acting in all directions, so for the purposes of base shear, it cancels itself out. If we were interested in designing a particular element (e.g. a beam, joist, or components/cladding), we would include both the external and internal pressures.

Hello, I am not sure if I understand your question. Please note that the figure that shows both the 11.4 psf and the 17.4 psf is a plan view (not an elevation view).

Good day. This is a good question. This is one of the updates of ASCE 7-22. Equation 26.10-1 of ASCE 7-22 does not include "kd" as we have seen in previous versions of ASCE 7. The directionality factor (kd) is now included in the later chapters (27 - 30) when computing the various pressures "p" and forces "F".

@@robertmoorhead7871 Thanks for the kind words! Glad this could help. Good luck on the exam, I am sure you will nail it!

@@philodeus7639 Thank you for the kind words. Glad this helped! Please share with others who may need some help.

@@mathandengineeringwithdr.a9515 you're very welcome!! I hope to watch more of your vids when I take foundation engineering aswell. Will be sure to recommend your channel !

Good day. This is a good question. This is one of the updates of ASCE 7-22. Equation 26.10-1 of ASCE 7-22 does not include "kd" as we have seen in previous versions of ASCE 7. The directionality factor (kd) is now included in the later chapters (27 - 30) when computing the various pressures "p" and forces "F".

@@mathandengineeringwithdr.a9515 I understand. Thank you for your response. Very helpful video!

@@prafooldev786 USA!

Thanks for your comment. "Principles of Foundation Engineering" by Das has a similar example as this video.

Hi Jessica, Thank you for your great questions! I split up my response to your question 2 into two parts. 1) For the base shear, think of this as an over-simplified vertical cantilever beam with a uniform load and the base is fixed to the ground. The base shear would be like the horizontal force reaction. All of that wind load on the walls has to go somewhere, and that somewhere is the base. Now, if we were going to investigate or design the roof diaphragm, we would consider pressures on the upper half of the wall height. But in this example, since we were explicitly asked about the base shear, we have to think of the base as an external support that all of the applied loads are transferred to. 2a) The minimum loads specified in Section 28.3.6 (8 psf on the roof and 16 psf on walls) are used when designing structural elements of the main wind for resisting system (MWFRS) and should be applied separately from the actual wind pressures. So, let’s say we are designing a roof beam that is part of the MWFRS. We apply the actual pressures to the building (like we did in the example) and determine the wind effects (W) on that beam (shear, moment, etc). We input these wind effects (W) into the load combinations and design the beam. We then, separately, apply the 16 psf and 8 psf to the building and determine the wind effects again (W) on that beam. We input the effects (W) due to these minimum pressures into the load combinations and check that the beam is still adequate. For the sake of this example, though, I was only intending to demonstrate how to compute base shear due to wind loading using the Envelope Procedure. 2b) Since the roof pressures actually relieve the total horizontal shear due to the windward roof pressure being larger than the leeward wind pressure and both sides of the ridge are experiencing suction, we can neglect the roof wind pressures by Section 28.3.3. i.e. The total horizontal shear is greater than that determined by neglecting the wind forces on the roof. [I probably should have stated that in the video somewhere.] Note, though, that if the windward side of the roof was in compression, we could not neglect the roof pressures since their horizontal components (projected on a vertical plane) would both add to the wall pressures (pointing to the right).

Nice! The equations for Kz beneath Table 26.10-1 would be the most correct to use since these capture the nonlinear nature of this relationship. Thus, using 1.09 (actually 1.088 when rounded to 4 sig figs for h = 20 ft) is the most correct. The advantage of the Table 26.10-1, though, is that you can directly read the values that are presented, and you are also permitted to use linear interpolation with the tabular values....which is helpful for quick calcs and when folks prepare for the PE. Since you created a nice spreadsheet, though, you can continue to use that. If you really want to have some fun with that spreadsheet, put some IF statements for the different z-domains and rig it up to handle all the exposure categories. Awesome stuff!

Thanks for your comment/question. Based on the definition of the "mean roof height" in ASCE 7, for roof angles less than 10 deg, the mean roof height IS PERMITTED to be taken as the roof eave height. So, this is an option but not a requirement. I took it as the actual mean height (20 ft) in part so I can just read the Kh value directly from Table 26.10-1 as 1.08. I will reply to your other comment regarding that value on your other post.

Thanks for your comment. This video is aimed at folks at the first-semester soil mechanics level, which cover this particular topic. I have a few other videos that cover other relationships, including what you mention. See links below: ua-cam.com/video/1LGJJrJA52o/v-deo.html ua-cam.com/video/K4Itl4T540g/v-deo.html

@@mathandengineeringwithdr.a9515 - perhaps an interesting story - probably for the pre-consolidation pressure determination - but my mentor studied under Terzaghi and Casagrande at Harvard (my mentor is 92 and still consulting) - anyway Casagrande came up to the Company's office in Toronto as he was consulting on one of our projects - anyway a young chap had done all the preconsolidation constructions on a number of samples and proudly showed them to Casagrande who looked at them and said - "well, this should be about here; and that one there" - but, the lad replied, I did them as per your procedure . . Casagrande looked at him and said - well, I had to develop something so the students would get in the right ball-park! Cheers

Yes. Thanks! Also, depending on how the dial gauge was zeroed, the readings will either decrease or increase in value. Regardless, though, the specimen height decreases during consolidation.

It depends on the specific material and the loading mechanism.