Heres another problem you might like to dismiss without debunking:
NIST continues in the tradition of Core Denial, with a number of misrepresentations, including, apparently, in the computer models that it supposedly used to simulate collapse initiation. Figure 6-9 shows sections of the global model for both the North and the South Towers. Both show the core columns to be thinner than the perimeter columns. But we know that the perimeter columns had outside dimensions of about 13.5 by 14 inches, and that most of the core columns had much larger dimensions. The outer row of core columns in each Tower apparently measured 56 by 22 inches for most of its height. We might forgive NIST for skimping on the dimensions of the core columns at the 100th floor of the North Tower, since the box columns apparently transitioned to smaller H-columns around the 100th floor, but their use of tiny core columns on the 85th floor of the South Tower is clearly in error.
This is a zoom-up of Figure 6-9 (p 96/146), which shows the "multifloor global model" for WTC 2, in which the top floor (pictured) is the 85th floor. Note the miniscule size of the core columns (the short, toothpick-like rods in the central area of the floor).
So your contention is that if the graphic display of the model at a magnification that allows the whole thing to be seen on-screen doesn't look
just like a photo of the structure the model is invalid?
Funny, if you go to NIST NCSTAR 1-6 and look at figure 4-28, Long span trusses of converted ANSYS model for floor 96 of WTC 1, or figure 4-29, Core floor beams and columns for converted ANSYS model for floor 96 of WTC 1(page 173 of the pdf), both of which are shown at a closer "zoom" than the multifloor model, it's clear that the core columns are graphically represented as wide-flange shapes.
But then, if you look at figure 4-40 and figure 4-41 (page 188 of the pdf), which show how the exterior panel assemblies were modeled in ANSYS, the columns appear to be mere lines and the spandrel plates look like some sort of net.
WTF is going on here? I think I might understand it; perhaps an analogy will help.
In the circuit simulation software I use, an MMBT5089 and an MJ15024 will both be represented, in the schematic view, by exactly the same symbol- the standard schematic symbol for an NPN bipolar junction transistor. But the former is a low noise, low level amplifier about the size of a matchhead and the latter is a 250V 16A 250W power device about the size of my thumb. The schematic symbol doesn't resemble what either looks like in the least. By CT logic, it's impossible for a simulation using either model to produce an accurate result.
But what's going on is that what shows in the schematic view is only a symbolic representation of a mathematical model. What's behind that "NPN BJT" symbol is a list of several dozen parameters which describe the transistor's electrical behavior. The models of different transistors use different values for these parameters, which is why they will behave differently when used in a simulated circuit.
Whether or not the schematic view from the sim software looks anything like how the circuit will look if built
doesn't have a @#$% thing to do with how well the model describes reality. All that matters is that the physical characteristics of the components be accurately described in numbers and that the mathematical methods used to derive and solve the system of equations that describes the entire circuit be correct.
In the structural simulations, what
matters is that the numerical descriptions of the columns, beams etc. and the properties of the materials they're made of be accurate and that the mathematical methods of solving the equations that describe the behavior of the structure they compose be correct.
Photo-realism or the lack of it is completely irrelevant because what you're looking at is simply a symbolic representation of a mathematical model. Claiming that the model is wrong because it doesn't meet your uninformed expectations of how it should look is just a demonstration of ignorance.
