There's this from wiki:
"Forensic engineering is the investigation of materials, products, structures or components that fail or do not operate or function as intended, causing personal injury or damage to property. The consequences of failure are dealt with by the law of product liability. The field also deals with retracing processes and procedures leading to accidents in operation of vehicles or machinery. The subject is applied most commonly in civil law cases, although it may be of use in criminal law cases. Generally, the purpose of a forensic engineering investigation is to locate cause or causes of failure with a view to improve performance or life of a component, or to assist a court in determining the facts of an accident. It can also involve investigation of intellectual property claims, especially patents."
and this:
"There is some common ground between forensic science and forensic engineering, such as scene of crime and scene of accident analysis, integrity of the evidence and court appearances. Both disciplines make extensive use of optical and scanning electron microscopes, for example. They also share common use of spectroscopy (infrared, ultraviolet, and nuclear magnetic resonance) to examine critical evidence. Radiography using X-rays (such as X-ray computed tomography), or neutrons is also very useful in examining thick products for their internal defects before destructive examination is attempted. Often, however, a simple hand lens may reveal the cause of a particular problem.
Trace evidence is sometimes an important factor in reconstructing the sequence of events in an accident. For example, tire burn marks on a road surface can enable vehicle speeds to be estimated, when the brakes were applied and so on. Ladder feet often leave a trace of movement of the ladder during a slipaway, and may show how the accident occurred. When a product fails for no obvious reason, SEM and Energy-dispersive X‑ray spectroscopy (EDX) performed in the microscope can reveal the presence of aggressive chemicals that have left traces on the fracture or adjacent surfaces. Thus an acetal resin water pipe joint suddenly failed and caused substantial damages to a building in which it was situated. Analysis of the joint showed traces of chlorine, indicating a stress corrosion cracking failure mode. The failed fuel pipe junction mentioned above showed traces of sulfur on the fracture surface from the sulfuric acid, which had initiated the crack.
Extracting physical evidence from digital photography is a major technique used in forensic accident reconstruction. Camera matching, photogrammetry, and photo rectification techniques are used to create three dimensional and top-down views from the two-dimensional photos typically taken at an accident scene. Overlooked or undocumented evidence for accident reconstruction can be retrieved and quantified as long as photographs of such evidence are available. By using photographs of the accident scene including the vehicle, "lost" evidence can be recovered and accurately determined.[1]"
and this:
"One of the first major inquiries conducted by the newly formed Railway Inspectorate was conducted by Captain Simmons of the Royal Engineers, and his report suggested that repeated flexing of the girder weakened it substantially. He examined the broken parts of the main girder, and confirmed that the girder had broken in two places, the first break occurring at the center. He tested the remaining girders by driving a locomotive across them, and found that they deflected by several inches under the moving load. He concluded that the design was flawed, and that the wrought iron trusses fixed to the girders did not reinforce the girders at all, which was a conclusion also reached by the jury at the inquest. Stephenson's design had depended on the wrought iron trusses to strengthen the final structures, but they were anchored on the cast iron girders themselves, and so deformed with any load on the bridge. Others (especially Stephenson) argued that the train had derailed and hit the girder, the impact force causing it to fracture. However, eye witnesses maintained that the girder broke first and the fact that the locomotive remained on the track showed otherwise"
and this:
"Causes of Failure
Structural failure does not have to be a "catastrophic collapse"; it may be a "nonconformity with design expectations" or a "deficient performance." Collapse is usually attributed to inadequate strength and/or stability, while deficient performance, or so-called serviceability problems, are usually the result of abnormal deterioration, excessive deformation, and signs of distress. In short, failure may be characterized as the unacceptable difference between intended and actual performance.
What can go wrong in the design-construction process and in the use of a structure that may result in immediate or eventual failure? A lot!
Negligence: failure to properly analyze or detail the design, or disregard codes and standards.
Incompetence: failure to understand engineering principles or respect the technical limitations of materials or systems.
Ignorance, oversight: failure to follow design documents and safe construction practices.
Greed: Short-cuts; intentional disregard of industry requirements and safe practices.
Disorganization: failure to establish a clear organization and define roles and responsibilities of parties.
Miscommunication: failure to establish and maintain lines of communication between parties.
Misuse, abuse, neglect: using the facility for purposes beyond its design intent or foregoing preventive maintenance.
Any one of these can be the underlying reason for an eventual failure of the structure and the resulting claims/disputes/litigations.
All of the parties on a construction project have legal responsibilities as defined by their contracts, and by state and federal laws. But professionals performing "value engineering" and "peer reviews" generally do not have liability for the safety of the constructed facility.
I don't feel we got our money's worth from NIST. I was surprised (aren't you?) that the key steel failiures were not located and tested?
So absent a reason for confidence in NIST I default to the position that they were "incompetent" or for some reason failed to produce the best fit explanations without having to essentially make up the inputs for the models (and 7wtc's didn't even match real world).
While details may not matter...broad strokes do...and use of "heat" as the broad stroke is not worth $16MM and reveals nothing we hadn't suspected back on 9/11/01.
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