The basic properties of steel are as follows: ____________ of the building materials Non-_________, resistant to _________ and dimensionally stable Consistent ___________ due to controlled industrial process used in its manufacture Relatively ___________, but strength and variety of forms enable it to be used in __________ quantities than other materials.

Strongest rotting / aging quality expensive / smaller p 258

The speed with which unprotected steel fails when it is exposed to a fire depends on several factors, including the following: _______ of the steel members __________ of the exposing fire ______ supported by the steel Types of ______________ used to join the steel members Type of _______

Mass Intensity Load connections steel p 260

Chapter 9 - Steel Construction Flashcards by Michael Baldwin

Steel is a _______ and ________________ building material.

strong and non combustible

p 257

How well did you know this?

Not at all

Perfectly

The basic properties of steel are as follows:

____________ of the building materials
Non-_________, resistant to _________ and dimensionally stable
Consistent ___________ due to controlled industrial process used in its manufacture
Relatively ___________, but strength and variety of forms enable it to be used in __________ quantities than other materials.

Strongest
rotting / aging
quality
expensive / smaller

p 258

How well did you know this?

Not at all

Perfectly

Steel is basically an alloy of _______ and _________.

iron / carbon

p 258

How well did you know this?

Not at all

Perfectly

Common structural steel has less than _______ _______ of one percent carbon.

three tenths

p 258

How well did you know this?

Not at all

Perfectly

Cast iron has a carbon content of _________ to ______ percent.

three to four

p 258

How well did you know this?

Not at all

Perfectly

The higher carbon content of cast iron produces a material that is _______ but _________.

hard / brittle

p 258

How well did you know this?

Not at all

Perfectly

The composition of steel can be altered by adding other materials. ______________, for example, can be added to increase strength. ____________ increases strength and toughness. ____________ increases the resistance of steel to abrasion.

Molybdenum / vanadium / manganese

p 258

How well did you know this?

Not at all

Perfectly

The lower carbon content of steel compared to that of cast iron results in a material that is _________ rather than brittle.

ductile

p 258

How well did you know this?

Not at all

Perfectly

Capable of being shaped, bent, or drawn out.

Ductile

p 258

How well did you know this?

Not at all

Perfectly

The rolling process consists of repeatedly passing ingots of steel heated to ________*F between large rollers until the desired shape is achieved.

2,200

p 258

How well did you know this?

Not at all

Perfectly

The ductility of steel allows it to be rolled in a ______ _______.

cold state

p 258

How well did you know this?

Not at all

Perfectly

A very commonly used steel for structural purposes is designated _______ ______.

ASTM A36

p 259

How well did you know this?

Not at all

Perfectly

Because excessive deformation of steel is undesirable, the maximum stress that develops within steel members under conditions of loading must be kept below the ________ ________.

yield point

p 259

How well did you know this?

Not at all

Perfectly

Steels for special application, such as those used in bridge strands, have strengths as high as __________ psi but very little __________.

300,000 / ductility

p 259

How well did you know this?

Not at all

Perfectly

Steel possesses two inherent disadvantages:

Tendency to _______ when exposed to air and moisture
Loss of __________ when exposed to the heat of a fire

rust
strength

p 259

How well did you know this?

Not at all

Perfectly

Steel can be protected in several ways from the formation of ______. Methods include painting the surface with a _______-inhibiting paint and coating the materials with ______ and ___________.

rust / rust / zinc and aluminum

p 259

How well did you know this?

Not at all

Perfectly

Steel can also be produced using ingredients that resist rust, as in the case of ___________ steel.

stainless

p 259

How well did you know this?

Not at all

Perfectly

The fires typically encountered by firefighters do not create temperatures hot enough to _______ steel. However, they do create enough heat to greatly ________ steal, resulting in structural failure.

melt / weaken

p 259

How well did you know this?

Not at all

Perfectly

Note that at a temperature of around 1000*F the yield point of the steel has dropped from ________ psi to approximately _______ psi.

36,000 / 18,000

p 259

How well did you know this?

Not at all

Perfectly

At 1200 *F the yield point has dropped to approximately ________ psi - a loss in strength of approximately _____ percent.

10,000 / 72

p 259

How well did you know this?

Not at all

Perfectly

The loss of strength because of increased temperature is not a _________ occurrence, rather, the steel loses its strength _________ as its temperature increases.

sudden / gradually

p 260

How well did you know this?

Not at all

Perfectly

The speed with which unprotected steel fails when it is exposed to a fire depends on several factors, including the following:

_______ of the steel members
__________ of the exposing fire
______ supported by the steel
Types of ______________ used to join the steel members
Type of _______

Mass
Intensity
Load
connections
steel

p 260

How well did you know this?

Not at all

Perfectly

Although steel is a good conductor of heat, it is also a very heavy material, having a density of around ______ pounds per cubic feet.

490

p 260

How well did you know this?

Not at all

Perfectly

A wide flange steel beam 14 inches in depth with a 10 inch wide flange would have a weight of ____ pounds per foot of length. A beam 20 feet long would weigh _______ pounds.

74 / 1480

p 260

How well did you know this?

Not at all

Perfectly

When lower _________ exist in the steel, it must be heated to a higher temperature for the yield point to be reached.

stresses p 260

When individual steel members are rigidly ________ and _______ into a large structural system, they are better able to resist failure than if they are simply supported.

welded or bolted p 260

The amount of expansion for slender members, such as beams and columns, can be determined through a property known as the linear coefficient of __________ __________.

thermal expansion p 260

If an unrestrained steel beam 20 feet long were heated from 70*F to a uniform temperature of 1000*F, it would expand _____ inches.

1.4 p 260-261

The basic method by which steel is used in the design of buildings is the construction of a structural framework that supports the _______, _______, and exterior _______.

floors, roof, and exterior walls p 262

- Large, horizontal structural member used to support joist and beams at isolated points along their length.

Girder p 262

Beams and columns in steel frame buildings are connected by one of two methods: __________ or _________.

bolting or welding p 262

The connections of a beam to a column not only transfers the _______ between members but also determines the _________ of the basic structure.

loads / rigidity p 263

Beam and girder steel frames can be classified as _______, ________, or _____-_______.

rigid, simple or semi-rigid p 263

When a framing system is classified as a ________ frame, the connection between the beams and the columns are designed to resist the bending forces resulting from the supported loads and lateral forces.

rigid p 264

In a rigid frame connection, sufficient rigidity exists between the beam and the column so that ____ ________ occurs in the angle between the beam and the column as the loads are applied.

no change p 264

In the case of a simple frame, the joints are designed primarily to support a __________ force.

vertical p 264

Simple frame: A degree of __________ change between beams and columns can occur if some form of diagonal bracing is not provided.

angular p 264

In a semi-rigid frame, the connections are not completely rigid but provide some ____________ support to the structure.

diagonal p 264

When rigid connections are not used, lateral stability for a frame must be provided through the use of __________ bracing or ________ _________.

diagonal / shear panels p 264

________ ________ are reinforced walls located between columns and beams to brace them laterally.

Shear panels p 264

________ _________ provide a structural member that can carry loads across greater spans more economically than beams can.

Steel trusses p 264

Steel trusses: They are frequently used in three-dimensional space frames, in which case they are known as _______ trusses because the cross-section resembles the Greek letter _______.

delta / Delta p 264-265

Two commonly encountered applications of the basic steel truss are the ______ _____ joist and the joist ________.

open web / girder p 265

Open web joist are mass produced and are available with depths of up to ____ feet and span up to ______ feet. However, they are more frequently found with depths less than ____ feet and spans of ____ feet.

6 / 144 / 2 / 40 p 265

- Open web truss constructed entirely of steel, with steel bars used as the web members.

Bar joist p 265

When round bars are used for the diagonal members, the open web truss is known as a ______ _______.

bar joist p 266

________ _________ are heavy steel trusses used to take the place of steel beams as part of the primary structural frame.

Joist girders p 266

Gabled rigid frames: Steel rigid frames usually are used for spans from _____ to ______ feet and are fabricated by welding or bolting together steel shapes and plates.

40 to 200 p 267

Gabled rigid frames: The top of the rigid frame is known as the ________ and the points where inclined members intersect the vertical members are known as the ________.

crown / knees p 267

Steel arches are used to support roofs on buildings where large unobstructed ________ are needed. These include occupancies such as _____________ and ____________ _______.

floors / gymnasiums / convention halls p 267

Steel arches can be constructed to span distances in excess of ______ feet.

300 p 267

A ________ arch is constructed as a solid arch that may be built up from angles and webs with cross section similar to that of a beam.

girder p 267

A ________ arch is built using truss shapes with pin connections. The pin connections allow for slight movement between two halves due to ____________ or _____________ change.

trussed / settling / temperature p 267

The strength of steel is such that it can be used in very slender forms such as ______ and ________.

rods / cables p 268

Drawing steel bars through a ______ to produce wire greatly increases the strength of the steel.

die p 268

It is possible to produce wire for use in bridge cables with strengths as high as ___________ psi.

300,000 psi p 268

Because of the high compressive strength of steel, the cross section of steel columns can be very small compared to their to ________. Because of this slenderness, the possibility of ___________ is greater with steel columns than with columns made of other materials.

length / buckling p 268

The most common column cross-sections are the hollow _________, the rectangular _______ and the wide ________ shape similar to the cross sections of an I-beam.

cylinder / tube / flange p 268

Steel columns A property of a given column, known as its "______________ _______" is used in combination with the condition of the column end to determine the load that can be safely supported without buckling.

"slenderness ratio" p 269

The ___________ the numerical value of the slenderness ratio, the more likely it is that buckling will occur. In general, columns used for structural support in buildings should not have a slenderness ratio greater than ______.

higher / 120 p 269

Columns that are erected so they cannot _________ at their ends have less tendency to buckle than columns that are free to _________ at their ends.

rotate / rotate p 269

A very common floor design in steel frame buildings uses a lightweight concrete with a minimum thickness of ____ inches supported by __________ steel decking.

2 / corrugated p 270

Light gauge steel joist: The steel joist are produced with depths of ____ to ____ inches and can be spaced _____ to ____ inches apart depending on the span and the load to be supported.

6 to 12 / 16 to 48 p 270

The rigid connections used in the beam and girder type of frame have a greater _______ of _________ at the point of connection than do simple connections. Therefore, it takes much more heat to produce failure in _______ connections than it does in the less massive simple connections.

mass of steel / rigid p 270

Although the primary purpose of a gusset plate is to strengthen the connection, the gusset plate also increases the _______ _______ at the connection, thereby decreasing it possibility of failure.

steel mass p 271

In gabled rigid frame structures the ______ _______ between the roof and the wall will be the strongest part of the frame and the last part to fail.

knee joint p 271

In a structure with a large beam and girder frame made of repeating sections, the adjacent sections of the frame tend to be mutually ___________. These adjacent sections provide a degree of _____________ to the overall system that reinforces the structures strength.

supporting / redundancy p 271

If steel trusses are constructed with ________ chords and ___________ members and are simply supported on a bearing wall or beam, they can easily fail and collapse under fire conditions.

slender / diagonal p 272

A steel column encased in 3 inches of concrete with a siliceous aggregate would have a fire resistance of ______ hours.

four p 272

__________ can be used as an insulating material either in the form of flat boards or a plaster.

Gypsum p 272

Gypsum board is available as _________ or _________.

regular or type X p 272

Gypsum consists of approximately _____ percent entrapped water.

21 p 272

Gypsum The water turn to steam upon exposure to fire and, in doing so, absorbs the heat. This process is known as ___________.

calcination p 272

The most commonly used spray-applied fire resistive materials (SFRMs) are _________ fiber or expanded aggregate coatings such as ___________ and _________.

mineral / vermiculite / perlite p 273

The applied fireproofing can vary from ____ to ____ inches to produce a fire resistive rating of ___ to ___ hours.

7/8 - 1 7/8 / 1 to 4 p 273

______-_________ mineral fibers are relatively soft and can be easily dislodged from the steel.

Low-density p 273

High density SFRMs that use magnesium oxychloride have densities ranging from _____ to _____ lb/cu ft.

40 to 80 p 273

- Containing or composed of cement. Has cement like characteristics.

Cementitious p 273

The cementitious materials have densities varying from _____ to _____ lb/cu ft.

15 to 50 p 273

- Coating or paint like product that expands when exposed to the heat of a fire to create an insulating barrier that protects the material underneath.

Intumescent coating p 274

Intumescent coating The coating material will expand to _____ to ____ times its original volume. The expanded coating then acts as an ___________ material to protect the steel.

15 to 30 / insulating p 274

_________ coatings function in a manner similar to intumescent coatings except they are based on more complex organic materials and their reaction to heat is more complex.

Mastic p 274

- Usually refers to a suspended, insulating ceiling tile system.

Membrane ceiling p 274