Chapter 9 Flashcards
Primary two metal alloyed in steel are
Iron
Carbon
The 4 Basic properties of steel includes
Strongest of the common building materials
Non Rotting resistant to aging and dimensionally stable
Consisten quality from controlled industrial manufacturing process
relatively expensive but strength and other qualities enable it to be used in smaller quantities that other materials
One disadvantage of steel
Is the tendency to rust
3 ways to protect steel from rusting are
Painting the surface with a rust inhibiting paint
Coating the matererial with since or aluminum
Adding alloy elements that resist rust
3 elements added to increase attributes
Molybdenum -Strength
Vanadium- Strength and toughness
Manganese- Resistance of steel to abrasion
Rolling process consist of
Repeatedly passing ingots of steel heated to 2,200f between large rollers untill the intended shape is achieved
Commercial and drawing steels, shaped after cooling below its recrystallization temperature by being passed through a series of rollers to reduce the thickness incrementally
Cold Rolled Steel (CRS)
Cold rolled steel CRS is used for
IS used for member that have a thin cross section such as floor and roof decking and wall studs
Unrestrained steel beam 20 feet can expand
1.4 inches
Characteristic most significant to the fire service in steel is
The deterioration of steel strength at elevated temperatures
Temperatures hot enough to weaken steel to its yield point
1,200 f
A steel column in encased in 3 inches of concrete with a siliceous aggregate would have a fire resistance of
4 hours
Sprayed applied fire resistive materials SFRM two most common used are
Mineral fiber
Expanded aggregate coatings such as vermiculite and perlite
The applied fire proofing can vary from 7/8 to 1-7/8 to give a rating of
1-4 hours
High density SFRMS that use magnesium oxchoride have densities ranging form
40 to 80 lb/ft
Cementious materials ingredients (4)
Portland cement
Gypsum
Perlite
Vermiculite
Gypsum board is available in two types
Regular
and type X
A board that contains additives to increase its fire resistance and is usually required where specified fire resistance is desired is
Type x Gypsum board
Intumescent coating will expand
15 to 30 times its original volume
Intumescent coating are applied as ____ and have a thickness of
Paint
0.03 to 0.4
3 Advantages included for intumescent coatings
lighter weight
durable surfaces
good adhesion
the most common method is to use membrane ceiling is
to use mineral tiles in a steel framework suspended by wires
The use of membrane ceiling can proved a fire rating of
1-3 hours
two important reasons for the design of the connections in steel frame buildings is
the connection of a beam to a column transfers the loads between members
connections determine the rigidity of the basic structure
