Hi,
For an isolated pad footing, when it needs to resist horizontal force from the column, is it normal industry practice to take into the account the weight of soil above the footing (lets say 3 feet of soil, if the footing thickness is 1 feet and the bottom of footing is 4 feet below grade)...
The top and bottom flange of Channel restrained then would be ok to dive in the moment connx. direction,Since its like built tup section, the unbraced length can be more for your C-Channels. Is it not possible to use HSS?
Thank you, the Cb factor for moment capacities for this stuff, is it better to leave it at 1 or leave it to program computed Cb values (This gives higher capacity)?
Hi,
There is a huge opening of approx. 31'(Height) and 50' Long opening in a secant pile shaft.. The hoop forces (compression- due to soil pressure) are huge around the lines of 35 to 60 Kip/feet (From Geo tech software). This creates a huge moment of 5500 Kip-ft approx. between the openings...
When the bricks are connected back to the wall with ties, if the angle wants to twist or buckle out it has to pull out the bricks that are tied to the wall which is really hard to happen (considering all those brace force and fun stuffs)....... The effective length could be considered as the...
Thank you!,
So if a floor decking in the form of metal deck is introduced to span between secondary beams, in this case a diaphragm action is achieved, So now would it be ok to consider the braces length as 5' on the main beams ?
Hi,
When there are primary beams 30 foot long on 5 or 6 rows and there are secondary beams connected to the primary beams at 5'-0" O.C via full-depth stiffeners and both beams are flush ( at the same level). Assuming there is no decking or flooring diaphragm spanning and connected to the...
Thank you Skeletron, If we are looking for the actual frame itself, like let's say a portal frame with 5 kips as the horizontal seismic force, calculated according to 4.1.8.11 V= S*(Ta)Mv*Ie*W/ (Rd*Ro) Rd=1.5&Ro=1.3 for conventional moment resisting frames.....Now when checking for the...
So in ASCE the connection design forces to be designed for an over strength factor, so similar to over strength factor what would be the amplification factor for connection forces for Canadian seismic? Appreciate it!
Hi,
In Canada, for seismic connection force, according to clause 4.1.8.18. " connections to structure shall be designed to accommodate building deflections" and the building deflections are amplified by multiplying Rd*Ro to get the realistic displacements, so that implies that the connection...
Thank you KootK! I 've seen in some of the drawings where the Engineers noted that the tie joist to be designed for 5 or 10 Kips axial load, could I use this case and provide the note for the forces I would get in this scenario, it would be somewhere around 5 kips or less
Hi,
I have an interior mezzanine (4 sides rectangular box). The framing goes like this with Steel beam, columns and Open web steel joist running perpendicular to the beams. As far as the lateral stability is concerned I can do moment frame in the beam to column lines on two sides, however in...
Hi,
Its a basic concept, but got too carried away. Have the main beam to col. fixed connx. in the plane of main BM. and have the roof beams running perpendicular to main beam with metal deck perpendicular to roof beam. In this case can I consider the column to be laterally supported in both...
Jayrod12,
If we are to use the full Wind load for allowable bearing pressure, then those combinations vary from the ASCE7-16 ASD combos for foundation approach right, it becomes more coservative
Jayrod12,
Agree with 1.4 factor for strength design (LRFD), but since I am dealing with Allowable bearing pressure of soil instead of the Ultimate factored bearing pressure, I tend to consider the Wind Load factors as a SLS for ASD methodology rather than a ULS for the footings.
Thank you, it makes sense, for the foundation design the wind load to be considered only 70% as the effective load for foundation design as per NBCC, so then if I apply my importance factor of 0.75*0.7, then the wind load will only be 0.525 in the combinations does that sound reasonable as per...
Hi,
For the foundation bearing pressure checks in NBCC for Wind loads I see the SLS importance factor as 0.75. So when checking the footings can I apply this reduction factor of 0.75 For Wind. So one of the load combo will be D+0.75W.
In ASCE it makes sense with ASD load combinations as they...
