Originally posted by baumusc
A large portion of the core on multiple floors was damaged or destroyed by the collision. They explain that in the video. Architects were actually amazed that the buildings stood as long as they did with all the damage done to them.
Also don't forget that the WTC buildings were really the first of their kind. Light weight components. Thin layers of fireproofing. There was obviously major damage to the core which is why you see buckling occurring on the outer trusses with a deflection of up to 55" right before the collapse. You also haven't answered one simple question. If this was a demolition how did they set up c4 or thermite or whatever you are claiming at exactly the correct floor where the maximum damage occurred and where it is obvious the collapse begins? Also how did those charges possibly survive the initial explosion from the plane crash.
Since I do not have that inside knowledge, everything I have tried to teach you is invalid. I could make an assumption, much like with ACE elevator (we know how that went for you guys.... "now you're blaming an entire elevator company... you're cray cray". Even though you asked who would have access, and I showed you a group who had access, then disappeared. I will give it a shot though!
Originally posted by MIT
(1) Type. Select steel-cutting charges that operate with a cutting effect. Percussive charges
are not very effective for steel cutting. Plastic explosive (C4) and sheet explosive (Ml 18) are best.
These explosives have very effective cutting power and are easily cut and shaped to fit tightly into
the grooves and angles of the target. These explosives are particularly effective when demolishing
structural steel, chains, and steel cables.
(2) Placement (Figure 3-7). To achieve the most effective initiation and results, ensure that—
The charge is continuous over the complete line of the proposed cut.
There is close contact between the charge and the target.
The width of the charge’s cross section is between one and three times its thickness. Do
not use charges more than 6 inches thick because you can achieve better results by
increasing the width rather than the thickness.
Long charges are primed every 4 to 5 feet. If butting C4 packages end to end along the
line of the cut, prime every fourth package.
The direction of initiation is perpendicular to the target
Size. The size of the charge is dictated by the target steel’s type and size and the type of
charge selected. Use either C4 or TNT block explosives for cutting steel. C4 works best. Each
steel configuration requires a unique charge size.
(a) Block charge. Generally, the following formula will give you the size of charge necessary
for cutting I-beams, built-up girders, steel plates, columns, and other structural steel sections. (When
calculating cutting charges for steel beams, the area for the top flange, web, and bottom flange must
be calculated separately.) Built-up beams also have rivet heads and angles or welds joining the
flanges to the web. You must add the thickness of one rivet head and the angle iron to the flange
thickness when determining the thickness of a built-up beam’s flange. Use the thinnest point of the
web as the web thickness, ignoring rivet-head and angle-iron thickness. Cut the lattice of
lattice-girder webs diagonally by placing a charge on each lattice along the line of the cut. Use
Tables 3-2 and 3-3 (page 3-10) to determine the correct amount of C4 necessary for cutting steel
sections. Use the following formula to determine the required charge size (Table 3-3, page 3-10,
is based on this formula)
FM 5-250
Section III. Special Cutting Charges
3-7. Purpose.
When time and circumstances permit, you can use the special cutting charges
(ribbon, saddle, and diamond charges) instead of conventional cutting charges. These charges may
require extra time to prepare, since they require exact and careful target measurement to achieve
optimal effect. With practice, an engineer can become proficient at calculating, preparing, and
placing these charges in less time than required for traditional charges. Special cutting charges use
considerably less explosive than conventional charges.
Use plastic-explosive (M112) or
sheet-explosive (Ml18 or Ml86) charges as special charges.
C4 requires considerable cutting,
shaping, and molding, which may reduce its density and, therefore, its effectiveness. Sheet
explosive is more suitable than C4, since sheet explosive is more flexible and requires less cutting.
Use of these charges requires considerable training and practice. The charges are thin and require
blasting caps crimped to a detonating-cord branch line for initiation. (A detonating-cord knot will
work but is difficult to place and can ruin the advantage of the special charge shape).
3-8. Ribbon Charges.
Use these charges to cut flat, steel targets up to 3 inches thick (Figure 3- 11).
Make the charge thickness one-half the target thickness but never less than 1/2 inch. Make the charge
width three times the charge thickness and the length of the charge equal to the length of the desired
cut. Detonate the ribbon charge from the center or from either end. When using the ribbon charge
to cut structural steel sections, place the charge as shown in Figure 3-12. The detonating-cord branch
lines must be the same length and must connect in a junction box (Figure 2-35, page 2-27). Example
A-5 (page A-5) shows how to calculate steel-cutting charges for steel plates. The formula for the
ribbon charge is as follows:
a.
Charge Thickness.
The charge thickness equals one half the target’s thickness; however, it
will never be less than 1/2 inch.
b.
Charge Width.
The charge width is three times charge thickness.
c.
Charge Length.
The charge length equals the length of the desired cut.
So we know that there are several different types of charges and explosives that can be used
now, on to some others and how to attach them
Originally posted by
In actual fact, thermite
also “
can
” cut through a structural steel target material
in less than one second
.
Moreover, there are at least two devices that have
the capability of cutting through steel
in a matter of
fractions
of a second.
Linear Thermite Cutting Apparatus; US Patent
Application No. 2006/0266204.
The term “generally adjacent” is further defined
as requiring the nozzle to be approximately 1/16 in
ch to ¼ inch away from the target
material (depending on the thickness of the materia
l to be cut
The ease that such devices can be attached to a tar
get surface is quite evident, and can be
accomplished by various conventional meansFor example, the device patented in Febr
uary 2001 indicates that conventional
fuses from “Pyrofuse Corporation in Mt. Vernon, N.Y.
” may be utilized as the activation
device and can be accessed for
remote ignition
Spectre
Corporation tested the device on various target ma
terials. The cutting time was between .4 (point
four) seconds, and 2 (two) seconds for an I-beam.
The number of cutters needed for an I-beam
test were 3 devices (“ganged”).These were then atta
ched to the I-beam with either a simple
“bracket” or a “rare earth magnet.”
See, US Patent Application No. 2006/0266204 (appl
ication published, Nov. 30, 2006), where
it states: A “linear thermite charge’s modular uni
t design will allow adaptation for a desired
geometry and will be easily deployed in the field.”
See also, US Patent No. 6183569, where it
states: “The present invention also provides a form
able, and separately storable, thermite powder
charge...” In addition, several embodiments mentioned
in US Patent Application No.
2006/0266204 provide that the devices can be deploy
ed in the field with a smaller degree of
preparation and “preconditioning” of the target. In
fact, thermite cutting device kits can be
provided, which contain “modular linear thermite ch
arges,” connectors, wiring, mounting
mechanisms, and an ignition system. Remote detonati
on can be accomplished as stated in, US
Patent 6183569 (Feb. 6, 2001).
xvii
See US Patent No. 6183569, where it states that in
one embodiment, the “ganged apparatus” is
“accessible for receiving external or remote activa
tion.”
edit to add source http://web.mit.edu/semenko/Public/Military%20Manuals/Explosives%20and%20Demolitions/CH3.PDF
And say sorry bout the pdf to forum fail.... my bad
A large portion of the core on multiple floors was damaged or destroyed by the collision. They explain that in the video. Architects were actually amazed that the buildings stood as long as they did with all the damage done to them.
Also don't forget that the WTC buildings were really the first of their kind. Light weight components. Thin layers of fireproofing. There was obviously major damage to the core which is why you see buckling occurring on the outer trusses with a deflection of up to 55" right before the collapse. You also haven't answered one simple question. If this was a demolition how did they set up c4 or thermite or whatever you are claiming at exactly the correct floor where the maximum damage occurred and where it is obvious the collapse begins? Also how did those charges possibly survive the initial explosion from the plane crash.
Since I do not have that inside knowledge, everything I have tried to teach you is invalid. I could make an assumption, much like with ACE elevator (we know how that went for you guys.... "now you're blaming an entire elevator company... you're cray cray". Even though you asked who would have access, and I showed you a group who had access, then disappeared. I will give it a shot though!
Originally posted by MIT
(1) Type. Select steel-cutting charges that operate with a cutting effect. Percussive charges
are not very effective for steel cutting. Plastic explosive (C4) and sheet explosive (Ml 18) are best.
These explosives have very effective cutting power and are easily cut and shaped to fit tightly into
the grooves and angles of the target. These explosives are particularly effective when demolishing
structural steel, chains, and steel cables.
(2) Placement (Figure 3-7). To achieve the most effective initiation and results, ensure that—
The charge is continuous over the complete line of the proposed cut.
There is close contact between the charge and the target.
The width of the charge’s cross section is between one and three times its thickness. Do
not use charges more than 6 inches thick because you can achieve better results by
increasing the width rather than the thickness.
Long charges are primed every 4 to 5 feet. If butting C4 packages end to end along the
line of the cut, prime every fourth package.
The direction of initiation is perpendicular to the target
Size. The size of the charge is dictated by the target steel’s type and size and the type of
charge selected. Use either C4 or TNT block explosives for cutting steel. C4 works best. Each
steel configuration requires a unique charge size.
(a) Block charge. Generally, the following formula will give you the size of charge necessary
for cutting I-beams, built-up girders, steel plates, columns, and other structural steel sections. (When
calculating cutting charges for steel beams, the area for the top flange, web, and bottom flange must
be calculated separately.) Built-up beams also have rivet heads and angles or welds joining the
flanges to the web. You must add the thickness of one rivet head and the angle iron to the flange
thickness when determining the thickness of a built-up beam’s flange. Use the thinnest point of the
web as the web thickness, ignoring rivet-head and angle-iron thickness. Cut the lattice of
lattice-girder webs diagonally by placing a charge on each lattice along the line of the cut. Use
Tables 3-2 and 3-3 (page 3-10) to determine the correct amount of C4 necessary for cutting steel
sections. Use the following formula to determine the required charge size (Table 3-3, page 3-10,
is based on this formula)
FM 5-250
Section III. Special Cutting Charges
3-7. Purpose.
When time and circumstances permit, you can use the special cutting charges
(ribbon, saddle, and diamond charges) instead of conventional cutting charges. These charges may
require extra time to prepare, since they require exact and careful target measurement to achieve
optimal effect. With practice, an engineer can become proficient at calculating, preparing, and
placing these charges in less time than required for traditional charges. Special cutting charges use
considerably less explosive than conventional charges.
Use plastic-explosive (M112) or
sheet-explosive (Ml18 or Ml86) charges as special charges.
C4 requires considerable cutting,
shaping, and molding, which may reduce its density and, therefore, its effectiveness. Sheet
explosive is more suitable than C4, since sheet explosive is more flexible and requires less cutting.
Use of these charges requires considerable training and practice. The charges are thin and require
blasting caps crimped to a detonating-cord branch line for initiation. (A detonating-cord knot will
work but is difficult to place and can ruin the advantage of the special charge shape).
3-8. Ribbon Charges.
Use these charges to cut flat, steel targets up to 3 inches thick (Figure 3- 11).
Make the charge thickness one-half the target thickness but never less than 1/2 inch. Make the charge
width three times the charge thickness and the length of the charge equal to the length of the desired
cut. Detonate the ribbon charge from the center or from either end. When using the ribbon charge
to cut structural steel sections, place the charge as shown in Figure 3-12. The detonating-cord branch
lines must be the same length and must connect in a junction box (Figure 2-35, page 2-27). Example
A-5 (page A-5) shows how to calculate steel-cutting charges for steel plates. The formula for the
ribbon charge is as follows:
a.
Charge Thickness.
The charge thickness equals one half the target’s thickness; however, it
will never be less than 1/2 inch.
b.
Charge Width.
The charge width is three times charge thickness.
c.
Charge Length.
The charge length equals the length of the desired cut.
So we know that there are several different types of charges and explosives that can be used
now, on to some others and how to attach them
Originally posted by
In actual fact, thermite
also “
can
” cut through a structural steel target material
in less than one second
.
Moreover, there are at least two devices that have
the capability of cutting through steel
in a matter of
fractions
of a second.
Linear Thermite Cutting Apparatus; US Patent
Application No. 2006/0266204.
The term “generally adjacent” is further defined
as requiring the nozzle to be approximately 1/16 in
ch to ¼ inch away from the target
material (depending on the thickness of the materia
l to be cut
The ease that such devices can be attached to a tar
get surface is quite evident, and can be
accomplished by various conventional meansFor example, the device patented in Febr
uary 2001 indicates that conventional
fuses from “Pyrofuse Corporation in Mt. Vernon, N.Y.
” may be utilized as the activation
device and can be accessed for
remote ignition
Spectre
Corporation tested the device on various target ma
terials. The cutting time was between .4 (point
four) seconds, and 2 (two) seconds for an I-beam.
The number of cutters needed for an I-beam
test were 3 devices (“ganged”).These were then atta
ched to the I-beam with either a simple
“bracket” or a “rare earth magnet.”
See, US Patent Application No. 2006/0266204 (appl
ication published, Nov. 30, 2006), where
it states: A “linear thermite charge’s modular uni
t design will allow adaptation for a desired
geometry and will be easily deployed in the field.”
See also, US Patent No. 6183569, where it
states: “The present invention also provides a form
able, and separately storable, thermite powder
charge...” In addition, several embodiments mentioned
in US Patent Application No.
2006/0266204 provide that the devices can be deploy
ed in the field with a smaller degree of
preparation and “preconditioning” of the target. In
fact, thermite cutting device kits can be
provided, which contain “modular linear thermite ch
arges,” connectors, wiring, mounting
mechanisms, and an ignition system. Remote detonati
on can be accomplished as stated in, US
Patent 6183569 (Feb. 6, 2001).
xvii
See US Patent No. 6183569, where it states that in
one embodiment, the “ganged apparatus” is
“accessible for receiving external or remote activa
tion.”
edit to add source http://web.mit.edu/semenko/Public/Military%20Manuals/Explosives%20and%20Demolitions/CH3.PDF
And say sorry bout the pdf to forum fail.... my bad
Edited by wormser1971 on Dec 21, 2013 18:51:58
