More inconsistencies in your links....
From http://algoxy.com/conc/core.html#anchor1149808
The design was a "tube in a tube" construction where the steel reinforced, cast concrete interior tube, was surrounded with a structural steel framework configured as another tube with the load bearing capacity bias towards the perimeter wall with the core acting to reduce deformation of the steel structure maximizing its load bearing capacity. All steel structures with the proportions of the WTC towers have inherent problems with flex and torsion. Distribution of gravity loads was; perimeter walls 50%, interior core columns 30% core 20%.
Steel, no matter what temper, no matter what bracing is used, ends up with an overall flexation that exceeds design parameters for defining when deformations and failures occur. These were facts I learned from a documentary in 1990 about the construction of the north tower. Yamsaki's decision making process was outlined and rejected core designs identified.
Both the WTC 1 & WTC 2 towers had a rectangular cast concrete core structure formed into rectangular cells that had elevators and stairways in them.
And from http://www.ussartf.org/world_trade_center_disaster.htm
The structural system,derived from the I.B.M.building in Seattle, is impressively simple.The 208 ft facade is, in effect, a prefabricated steel lattice, with columns on 39 inch centers acting as wind braces to act on all overturning forces; the central core takes only gravity forces. A very light, economical structure results by keeping the wind bracing in the most efficient place, the outside of the building, thus not transferring the forces through the floor membrane to the core, as in most curtain-wall construction.
Do you see the contradiction here? algoxy says that the core provides the resistance to flex and torsion - from wind load, and ussartf says the exterior walls give the resistance to wind load.....
It can't be both...... To me it looks like algoxy is making shit up in order to advance the theory that the core was concrete.
And then there are numerous references in numerous docs that mention how office space was extended into the core wherever the elevator shaft was shorter.
Numerous counter evidence to your claim that the core was concrete.... Time to put that to rest unless you can come up with some building plans.....
From http://algoxy.com/conc/core.html#anchor1149808
The design was a "tube in a tube" construction where the steel reinforced, cast concrete interior tube, was surrounded with a structural steel framework configured as another tube with the load bearing capacity bias towards the perimeter wall with the core acting to reduce deformation of the steel structure maximizing its load bearing capacity. All steel structures with the proportions of the WTC towers have inherent problems with flex and torsion. Distribution of gravity loads was; perimeter walls 50%, interior core columns 30% core 20%.
Steel, no matter what temper, no matter what bracing is used, ends up with an overall flexation that exceeds design parameters for defining when deformations and failures occur. These were facts I learned from a documentary in 1990 about the construction of the north tower. Yamsaki's decision making process was outlined and rejected core designs identified.
Both the WTC 1 & WTC 2 towers had a rectangular cast concrete core structure formed into rectangular cells that had elevators and stairways in them.
And from http://www.ussartf.org/world_trade_center_disaster.htm
The structural system,derived from the I.B.M.building in Seattle, is impressively simple.The 208 ft facade is, in effect, a prefabricated steel lattice, with columns on 39 inch centers acting as wind braces to act on all overturning forces; the central core takes only gravity forces. A very light, economical structure results by keeping the wind bracing in the most efficient place, the outside of the building, thus not transferring the forces through the floor membrane to the core, as in most curtain-wall construction.
Do you see the contradiction here? algoxy says that the core provides the resistance to flex and torsion - from wind load, and ussartf says the exterior walls give the resistance to wind load.....
It can't be both...... To me it looks like algoxy is making shit up in order to advance the theory that the core was concrete.
And then there are numerous references in numerous docs that mention how office space was extended into the core wherever the elevator shaft was shorter.
Numerous counter evidence to your claim that the core was concrete.... Time to put that to rest unless you can come up with some building plans.....