...any advertiser. I couldn't publish in the NFPA Journal because I name names, he says.
Schulte also slams some other expert witnesses for allegedly false statements. They commit perjury, but it never gets out because lawsuits are often settled, he says.
Schulte says he never has been sued, though he expects to be. But he is not worried: As long as I have documentation, I can say whatever I want.
U.S. Building Fires | ||||
Fires (mil.) | Civilian deaths | Civilian injuries | Direct property damage ($ bil.) | |
1985 | 2.37 | 6,185 | 28,425 | 7.32 |
1986 | 2.27 | 5,850 | 26,825 | 6.71 |
1987 | 2.33 | 5,810 | 28,215 | 7.16 |
1988 | 2.44 | 6,215 | 30,800 | 8.35 |
1989 | 2.12 | 5,410 | 28,250 | 8.66 |
1990 | 2.02 | 5,195 | 28,600 | 7.82 |
1991 | 2.04 | 4,465 | 29,375 | 9.47 |
1992 | 1.96 | 4,730 | 28,700 | 8.3 |
1993 | 1.95 | 4,635 | 30,475 | 8.55 |
1994 | 2.05 | 4,275 | 27,250 | 8.15 |
1995 | 1.97 | 4,585 | 25,775 | 8.92 |
1996 | 1.98 | 4,990 | 25,550 | 9.41 |
1997 | 1.8 | 4,050 | 23,750 | 8.53 |
1998 | 1.76 | 4,035 | 23,100 | 8.63 |
1999 | 1.82 | 3,570 | 21,875 | 10.02 |
Source: NFPA |
U.S High-Rise Fires | ||||
Fires (thous.) | Civilian deaths | Civilian injuries | Direct property damage ($ mil.) | |
1985 | 23.4 | 73 | 850 | 125.2 |
1986 | 20 | 48 | 658 | 80 |
1987 | 18.3 | 73 | 856 | 72 |
1988 | 19.7 | 98 | 909 | 216.7 |
1989 | 19.5 | 121 | 915 | 183.7 |
1990 | 16.8 | 87 | 731 | 122.1 |
1991 | 17.8 | 40 | 832 | 216.3 |
1992 | 18.2 | 44 | 1,013 | 176.8 |
1993 | 15.3 | 45 | 831 | 86.2 |
1994 | 15 | 61 | 1,136 | 89.9 |
1995 | 13 | 56 | 758 | 65.6 |
1996 | 15.2 | 66 | 861 | 263.9 |
1997 | 14.4 | 46 | 633 | 144.1 |
1998 | 13.3 | 37 | 804 | 121.2 |
1999 | 15.3 | 39 | 708 | 80.8 |
Source: National estimates based on National fire incident reporting system survey |
Concrete Is No Better Than Steel for Structural Fire Resistance
Steel frames have been on the defensive since 9/11, when jet-fuel-triggered fires sapped the strength of the structure of the twin towers of the World Trade Center, ultimately finishing off the job the terrorists started. But sources say there is no preferred structural material for fire resistance. All building materials, including concrete, are fire-resistant, not fireproof, they say.
|
At higher temperatures, steel loses both yield and tensile strength, along with the modulus of elasticity. At 1,100° F, steel generally retains about half of the strength and stiffness it has at ambient conditions, according to the American Institute of Steel Construction in Facts for Steel BuildingsFire. This is comparable to the strength and stiffness reductions for ordinary concrete, says AISC.
Steel loses about 80% of its strength and stiffness at 1,300° F and almost all at about 2,200° F. Although likely deformed, fire-damaged steel will regain its pre-fire properties at ambient conditions, but there likely will be annealing and a reduction in yield strength. Fire-resistant steel, developed in Japan and not widely used in the U.S., has improved strength retention ratios at elevated temperatures, though it has similar variations in modulus of elasticity, says AISC.
Concrete spalls when exposed to elevated temperatures. This action exposes the reinforcing steel to the heat, causing the steel and structure to lose strength.
Spalling can be violent, like an explosion. The entrained water in concrete heats up in a fire, turns to steam and expands. The expansive force can be strong enough to...