Re: WTC e 9/11: é lecito fare una distinzione fra gestione dell'emergenza e responsabilità dell'atta

Inviato da  Henry62 il 24/8/2006 9:16:37

Ciao,
quando parlavo di "lezione tecnica" da imparare dala tragedia del WTC, pensavo a qualcosa di questo genere:

http://www.nist.gov/public_affairs/releases/final_towers_rpt102605.htm
http://wtc.nist.gov/recommendations/index.htm

oppure dal sito: http://vincentdunn.com/wtc.html

"Recommendations for constructing the new high rise buildings on ground zero
The steel columns, girders and floor beams should be encased in masonry or other more effective fire retarding material. Spray-on fire retarding is ineffective. Post fire investigations reveals the spray on fire retardant has scaled off and steel beams and concrete and steel floor slabs crack and allow flame spread.

Lightweight bar joists should not be used to support floors in high-rise buildings. The National Fire Protection Association has shown unprotected steel bar joist fail after five or ten minutes of fire exposure.

For life safety in high-rise buildings bring back the smoke proof tower. This allows people to escape fire using smoke free stairways.

Stairs and elevator shaft ways should be enclosed in masonry to prevent smoke spread.

Heating ventilation and air condition HVAC systems should be provided by unit system serving only one or two floors. Central air system serving 10 or 20 floors creates shaft ways and duct systems that penetrate fire rated floors walls partitions and ceilings. Smoke spreads throughout ducts of central HVAC systems.
The high rise building framework should be skeleton steel framing not center core steel column framing. There should be no bearing wall high rise construction. Reduce the size of open floor design.
Increase the thickness of concrete in floor construction. The two or three inches of concrete over corrugated steel fails during most serious high rise fires and must be replaced.
Automatic sprinklers should protect all high rise buildings. Firefighters can extinguish approximately 2,500 square foot of fire with one hose line. Two hose steams may quench 5,000 square feet of fire. The World Trade Center floor areas were 40,000 square feet in area.
Federal, State and Port Authority buildings should comply with New York City building codes and actually in some cases should exceed them. Remember building codes are only minimum standards. "

Spero di aver chiarito la mia posizione.
Ciao