It's hard to tell from your photo. It looks like a shallow unreinforced footing that was cast against soil? There could be a host of reasons for the settling including soft soils, poor drainage, utility drain excavation or structure built on loosely placed fill to level up prior to...
I would still have an engineer look at this to see if there is something I'm missing. But, could you span the entire 92"? If this beam is only carrying 250 lb, it seems like you could do something quite shallow. I would want to make sure the other spans do not have some sort of loading that...
I might take a little bit different approach to this. The center wall acts as a large column. I would consider modeling this as a moment connection since it is my thought that the rigidity would “make” the structure act this way.
In practicality, the approach I learned before we had easy...
I tend to think of these sorts of situations like I would a beam to column moment frame and design accordingly. So, in theory, it is possible to do this as PhamENG mentioned. If this is in place and the beam is close to capacity, it will be a difficult field weld to get right.
BUT, I don’t...
It is always good to get another input when designing. I detail and design by deflection when I layout a building or structure. The goal is to either reduce the deflection or accommodate the movement. I think your concern about story drift and unintentional bracing is a great example and...
I've not done a large parking structure. But, I did need to isolate a structure from an entry bridge to avoid temperature and unintentional "bracing" reactions on a retaining wall. I don't have access now to that detail. But, I used to design bridges in a previous life and I used the same...
I don’t know ETABS. But, could you model the base of the stair restraint as a “roller” rather than a pin? In other words no restraint in the “x” direction? I wonder if it should be detailed this way too for
Construction?
Yeah. This is a tough call for the owner especially since he is educated about this and not happy. Of course he could have been there for the placement...
"Hot" is a colloquial term, I guess. It means the concrete mix was at the point of hydration where it is setting rapidly. It is...
Remote location and road work. This batch plant is 90 minutes away by truck. There is a closer plant that is 60 min. out. The guys used to working here use that plant to buy another 1/2 hour. That with retarder and early AM placements usually do the trick. Lack of experience.
Thanks all for the input.
They are removing the forms tomorrow. I just received the mix tickets. The last load was 3:45 old at discharge and 4:15 minutes when they were trying to strike off the top to elevation. They were unable to install anchor bolts. The site is at over 9000 feet in...
Colorado. But, my spec is ASTM C94. The Building Official won’t give them a CO unless I approve any repairs. I can ask them to remove it...But, this will get ugly.
I did a, relatively, small building with high snow loads and some seismic. My situation was a bit different. The structure needed to transfer shear through dormers and valleys in each primary direction due to offset locations of moment frames.
My detail looked a lot like the OP’s. But, part...
Phameng
I am fortunate in that I design mostly structures in high snow load that has a bit of seismic. So, my typical snow old is 75 PSF and I use an average lateral load of 8% which is conservative. That calcs out to about what you use...about 7 PSF.
You are correct that the deck bracing...
Thanks for the comments! These are the stem walls. The tallest walls are 9 ft but only retain about 5 feet. Soils are text book perfect...mountain Valley gravels. Old buildings last 120 years so far on stone foundations. So, it’s hard to tell someone to rip out a $40 k foundation on a 1800...
Last night I got a frantic call from a homeowner/client who is a civil engineer about his new house foundation I designed.
Evidently, the concrete subcontractor placed the last truck at 3 hours out from the batch plant, placed it, tried to trowel the surface and left when it started raining. I...
PhamENG
Thanks. I've used a lateral restraint "technique" similar to steel restraint on a tall glulam beam restrained by floor sheathing. I just have not run this calc (which was not something I would want to run for every deck) on the design of a deck joist. My point was that 2x decking is...
bones206
This is an interesting question that comes up often in our field. Restraint of the compression side of structural members. You mentioned specific "testing that provides a design value". Honestly, I cannot find a design value for diagonal decking, wood planks or even plywood that...
If I understand the OP's original question he was asking, specifically, about the use of decking to provide unsupported compression restraint of the joists (top of the joist on simple spans). Not the global lateral stability of the deck structure.
Thanks for the response.
Since the upper building is part of the property that may allow you to push the limits of the excavation and layback. It also allows your geotechnical engineer to review the bearing of the upper building.
The wall 3 meters away from an existing building might be...
This is a great question. I have no theoretical basis for this. But, I always provide blocking at the third points and figure the decking provides compression zone restraint.
My justification is that I have observed dozens of floors in old houses where the wood flooring is the restraint and...
