If there is a lot of repetition, possibly consider a purpose made 300 wide precast lintel/beam for the top portion.
If there is not a lot of repetition then ask the architect if you can have 330 brickwork instead of a 300 cavity wall. This would then be easy to resolve.
For the manual calcs I would approach it as in sketch. Design in-slab beams (blue lines 1 to 4). Beams 1 to 3 important ones.
Then design simple panels (red) but not modelling the blue beams as support (except beams 5 & 6) with and without to check sensitivity.
When checking deflections...
The video evidence points to the first actual structural failure/collapse being the pool deck area, no disputing that from my side.
I don't have a theory, far too many unknowns, I'm just trying to figure out how the pool deck collapse was preceded by creaking in the walls above the Nirs. It's...
We all speculating of course but for interest sake, my thoughts have been that the sounds are of the masonry units taking up compressive stresses/strains as the vertical load on then slowly increases until they finally fail in crushing and/or buckling and then 'crash' onto the floor slab above...
The walls were cement masonry units so could inadvertently end up carrying vertical load. Just throwing some ideas out there but think about slab deflections, gaps between top of wall and slab (if any), vertical lengths of wall from level 1 to roof on façade, vertical load transfer accumulating...
Wow, this statement could really be seen in the wrong light. Yes, developers/architects push the limits to achieve their own agendas but I would seriously doubt that any engineer would knowingly ignore code requirements and compromise structural safety and serviceability to satisfy them. They...
Watching the crane collapse video, it seems like this general planter area really was in the wars. The crane 'collapse' appears to have dropped the elevator wall formwork onto the deck, bending over the column starter bars on Grid L8.
The crane itself seems to have dropped down onto M10 where...
This may be irrelevant to the general hunt but with reference to the 8” condo floor slabs.
Bending rebar: The top and bottom flexural reinforcement provided on the project is not really lacking, perhaps the placement over columns could have been better but there is not an alarming deficiency at...
I quoted warrenslo, not you! Sorry for the confusion.
Yes, I am uncomfortable with the PH support too. These edges (and others) are not comforting at all.
I would read nothing sinister into this.
floor drilling: I would suggest that he is trying to build a feel for the concrete strength as well as the make-up of the floor to determine the loads. During construction they would need to have raised the penthouse finished floor level above the roof...
I don't disagree and can't stand conspiracy stuff, just trying to make sense of the time lines and exploring options. When 111 was hearing noises the pool slab seemingly had not collapsed yet. But maybe it had already started elsewhere.
From the outset it seems obvious that the main collapse followed the pool deck collapse which caused instability. What is bothering is that 3 separate reports from 111, 611, 1211 (all above each other) report preceding creaking noises.
• 1211 (below top penthouse) 20 hours prior to collapse...
Hi Demented
Those depths you mention refer to the pile cap itself.
Pile depths - Given the 'bulb' at the bottom of the pile (shown on the drawing), this would indicate that these are driven, cast in-situ piles (Franki). Crudely explained, a steel tube (more or less 20" dia) is driven down...
What are the spans, column sizes and height, slab thickness, hole size required and approximate position on plan and the weight and position of the machine/ry.
A coefficient of 0.6 takes into account the difference between lab test and site strength. Then the materials safety factor for concrete in bearing is 1.5
So 0.6 / 1.5 = 0.4
Not that this caused the failure, but fully agree about the lateral stability in the East-West, it seems hopelessly insufficient. Laterally, the building is obviously relying on frame action and some bracing from internal walls and possibly a bit of ‘outrigger’ help from the slabs built into the...
My bet is this is where it started ('cars sinking into basement'). Punching failure and progressive collapse towards main tower and overloading columns I10 & K10. Load transferred on the demising walls on grid K (cracks seen rapidly opening in wall by resident on 6th floor), she got out in time...
