Here is the Shear Retrofit (above) update:
Full welding (but with rebar inserted) done at the full-open corner joints.
The welders use entirely 1/8" 6013 welding rod. It's supposed to be used on metal sheet only. What happened when it's use for full weld on a full-open corner joints?
Can the...
The welder put the shear retrofit in place (see photo above). He said he will put them first in all columns before doing full weld on the corners and top plates.
The top plate corner joints use half-open corner joint as centordollar suggested. But the corners at sides can't be done that way...
All the 16 pcs of baseplates have already been cut months ago. 4 sides for each column. So the half-open corner joint (your minimum throat thickness (<5mm) can only be done in between the top original baseplate and the top of the 4 sides. It can't be done for all the corners because the side...
Yes to encase the top of each column (first photo) with 4 pieces of 400mm (16") depth 5/8" thick baseplates at all sides (4 plates shown at 2nd photo) and welding all around and to the top of the original baseplate forming an iron cap (imagine 5 baseplates total in one concrete pedestral). To...
Thanks for all the tips. We were able to use cardboard (and some plywood) but aligning the edges of the cardboard/plywood to the column edges were difficult at first because the columns not perfectly rectangle.
Tomorrow we will have the baseplates drilled with the marking pen drawn on them. But...
No problem for 1 or 2mm of the edge gone but the problem is during explosive spalling of heated concrete, the debris can hit the welder body like grenade.
What material (list) has the most heat resistance (can't conduct much heat of the Shield Metal Arc Welding machine)?
Something that can be...
The concrete can't be removed because the top baseplate was already installed years ago with anchor bolts at the four corners. Imagine an old baseplate and concrete pedestal (with the top baseplate covering the entire top to the edge) The baseplate to be put at side is new. So I'm thinking what...
We need to put side baseplates right below the main baseplates. Both are 16mm thick (5/8 inch). It need to be full open corner joint like the above illustration and not flush or half open joint. The welder is an expert. But this configuration is not common. So I need to ask something here:
I...
Imagine post installed chemical epoxy anchor bolts. That is, sometimes you have to drill at 3 or 4 spots to avoid rebars that blocks the chemical bolts. Here you only know the anchor bolts exact locations after the bolts are epoxied. So how do you make the template this way for the machine shop...
A picture is worth a hundred words.. So how are you supposed to make new baseplate holes that are totally aligned with these anchor bolts that are already put? It's just example because I know it's too near the edge. It was an old photo before the baseplate was put and the anchor bolts hammered...
The columns have already existing cast-in-sitiu anchor bolts. We just have to let machine shop drill the baseplate holes to fit the position of the column existing anchor bolts without having the contractor hammer the anchor bolts again to fit the baseplates to-be-drilled holes.
If you made the hole a bit bigger. During shear sideway movement, the bolts nearest the hole edge at one side can go into bearing or shear failure first because you don't engage them all simultaneously, That is why, making baseplate holes same size as the anchor bolt or 1mm larger would be more...
It's for a column anchor bolts. I was just asking how do yo usually layout the hole.. like do you put the baseplate directly on the column and mark it or do you use films. So I need answer from practicing structural engineers. Because last time we did them, the holes were not aligned so the...
Hi,
(the above are 4 baseplates with 3 painted with epoxy (for the inner side) and first few holes marked with pen and the 4th baseplate showing the unpainted side).
Do you use cardboard or big paper and punch against the anchor bolts to layout the holes in the baseplates to be drilled by the...
There are no windows in the higher wall (7 storey) or the lower 3 storey.
The higher 7 storey building has only big columns in the left and right perimeter. They don't have columns in the middle of the building. So if the column in either side got burned let's say for an hour or two. The entire...
I'm one engineer of a waterproof subcon company and just learning basic structural engineering. Remember all structural engineers were once used to be ordinary engineer and learning from others. I review building waterproof and just study the structural members for comment to the code people...
In a fire with typical office paper fire load. What is the temperature usually at the top of the metal roof. Can it reach 1300 C? If it only reaches half or 700 C? The metal roof can't melt?
For those material with rated 1 hour or 2 hour fire rating.. what is the temperature usually considered?
But how many minutes before it can melt? 5 minutes? 15 minutes? or you mean 0 minutes? Please give me ideas how long in minutes.
What temperature before a metal roof melt?
I couldn't see even one picture of melted metal roof in the entire internet. Thanks.
This is the great reference about fire spread from lower roof that I read entirely.
https://www.branz.co.nz/pubs/research-reports/sr409/
But after hours of searching and even asking roof contractors, they don't know how long before a 0.5mm (0.02") metal roof can melt 3.5 meters high from fire...
HTURKAK and others,
HTURKAK wrote:
Ok let us focus on this as this is my main concern, the 60cm firewall extension above the roof. But first let's be clear we are talking of firewall in this context:
But the existing building I'm analyzing has one roof much lower than the adjacent...
