picture compare with Madrid fire
Nellewrites is essential correct, steel is a mavelous material but not indistructable, given enough prolonged to heat and load steel enters it plastic zone and is very maliable. You frequently see this in curved buildings where structural steel is heated a bent into special shapes. This process is reverseable within limits. In requard to WTC 7 structural collapse is explaining Wiki excerpt:
The original 7 World Trade Center was 47 stories tall, clad in red exterior masonry, and occupied a trapezoidal footprint. An elevated walkway connected the building to the World Trade Center plaza. The building was situated above a Consolidated Edison (Con Ed) power substation, which imposed unique structural design constraints. When the building opened in 1987, Silverstein had difficulties attracting tenants. In 1988, Salomon Brothers signed a long-term lease, and became the main tenants of the building. On September 11, 2001, 7 WTC was damaged by debris when the nearby North Tower of the World Trade Center collapsed. The debris also ignited fires, which continued to burn throughout the afternoon on lower floors of the building. The building's internal fire suppression system lacked water pressure to fight the fires, and the building collapsed completely at 5:21:10 pm. The collapse began when a critical internal column buckled and triggered structural failure throughout , which was first visible from the exterior with the crumbling of a rooftop penthouse structure at 5:20:33 pm.
Any architect or engineer can design a structure that would essentially last forever an example is a Roman Empire bridge which stands today. The only problem it was design to accommodate 2 ox carts not very practicial in today. So this is the ying and yang of design every architect/engineer faces today. Would you like carry a decade old bag cell phone, which wouldn't work on today 3/4G networks? Ed
The fire could burn down WTC and Pentagon but couldn’t burn a hair of a monitor and book?
The pentagon was not hit by a airliner. See for yourself
Typical quibble. Then how do you explain the collapse of WTC 7? There was no plane crashing into it.
WTC 7 collapse
Nice try. There was no damage to the structural integrity of the building in 1975, and the 2001 attack caused fires on multiple floors. The structural damage in 2001 was more than sufficient to take down the buildings once fire entered the mix for an extended period.
A bit on its construction...
Prior to the construction of the Twin Towers, skyscrapers were designed to support themselves through large internal columns spaced about 30 feet (9 meters) apart, which interrupted the flow of interior space. For this project however, the engineers came up with a different solution -- the exterior walls themselves would support the bulk of the structure, and they would get a boost from one single column of beams in the center.
(10) Another reason that we know the fires were not as serious as claimed, is that there are photos of people in the impacted region after the planes hit the building (and before it collapsed). The above photos show at least two survivors of the impact and the initial jet-fuel fire.
Actually, paper took out the WTC after it ignited. The jet fuel spent fairly quickly.
Because of the unique design - the buildings were not traditional construction, it was of a radical design where the weight carried along the outside walls and the inner core that housed the elevators. It eliminated the need for inner support posts every so many feet. When the walls were compromised and the paper fire heat buckled other parts, the upper floors fell. Their weight in momentum then pancaked the structure. Methinks the think site needs to do its own rethinking.
What is political about this?
"Resist, we much. Weï»¿ must, and we much. About that, be committed."