STD FINALS TERMS

Bessemer Process

A way to manufacture steel quickly and cheaply by blasting hot air through melted iron to quickly remove impurities.

Steel

An alloy made by combining iron and other elements-mostcommon is carbon

True

true/ false:

Steel is environmentally friendly, 100% recyclable

tensile, compression

Steel is high in __________ strength, low resistance to _______________

hot rolled steel

Common manufacturing process toproduce structural steel shapes. Wide-Flange I-Section Angle Bars Flat Plates Makes use of raw steel (steel billets)roll-pressed at very hightemperatures usually over 930⁰C(1700 ⁰ F) 10

cold formed steel

Made by rolling or pressing thin gauges of steel intopre-determined shapes. Ranges from 0.3mm to 6mm only

Built up sections

Welding together standardshapes to create desiredsection

-carbon steel

- high strength low alloy steels

- heat treated carbon

heat treated construction alloy steel

structural steel classes

elastic range

strain range, no permanent deformation

yielding/ plastic range

strain range where strain increases with no appreciable increase in stress

strain hardening

strain range where increase in strain is accompanied by a significant increase in stress

necking

Mode of tensile deformation where relatively large amounts ofstrain localize disproportionately in a small region of material Occurs just before failure

Yield Point, Yield Strength

Usually associated to the strength of the material The stress corresponding to a specified deviation from perfectly plastic behavior.

Ductility

An important property of steel which allows absorption and redistribution of stresses in continuous members and at points of high local stress caused by external forces.

Proportional Limit

Stress corresponding to the first visible departure fromlinear-elastic behavior. Has little practical significance and is not usually recordedin a tension test

Poisson's Ratio

Ratio of transverse to longitudinal strain.

Same for all structural steels

0.30 in elastic range

0.50 in plastic range

American Institute of Steel Construction

what does AISC mean

American Iron and Steel Institute

what does AISI mean

W SHAPE (Wide Flange)

steel shape Used as Beams, Columns, top & bottom chord of long span Trusses• Most Common, and commercially available locally.Source: ASEP Steel Handbook (1994)

S SHAPE

Previously referred to as I-beams Have relatively narrow flangeswith sloping interior face

yield strength or yield point

In designing steel members the________________________ will dictate the sizes of the sections.

yield point (Fy)

All allowable stresses will stem from the value of the _______

A36 or 36 ksi (248MPa)

A50 or 50 ksi (347 MPa) by special order

Locally available Fy of steel section

Allowable Stress Design

waht does ASD mean

Load and Resistance Factor Design

What does LRFD stand for?

less than or equal to

actual stress is ____________ to allowable stress

0.66 Fy

compact section allowable bending stress (Fb)

0.60 Fy

non-compact section allowable bending stress (Fb)

A307 steel

common bolts are classified by ASTM as

True

True or False:L-shapes can have equal or unequal legs.

Snug Tight Condition

The tightness that exists when all plies in a joint are in firm contact

Smaller safety factor against slippage

In a bearing type of connection, the allowable stress is higher because of:

AISC

What association was founded in 1921 as a non profit, technical institute and trade association for the use of structural steel in the construction industry?

Can be disassembled easily

advantage of bolted connections compared to riveted and welded connections?

Bolted connections

the most common and economical connection used?

gage

The center-to-center distance of bolt lines perpendicular to axis of member.

Rivets, Bolts, Welds

Individual parts or members assembled together compose every structure. These members must be fastened together by means of:

Local flange buckling may occur

What happens when the flange width-to-thickness ratio (bf/tf) exceeds the prescribed limit?

Oversized Hole (OVS)

Which type of bolt hole has a diameter larger than the bolt diameter, requiring hardened washers for bearing applications in outer plies?

compact steel beam section

A beam with a flange-to-thickness and web-to-thickness ratio within code limits

KL/r

formula for slenderness ratio

It fills the hole and shrinks, providing a clamping force.

What happens to the shank of a hot-driven rivet as it cools?

all criteria

for a section to be considered as compact how many criteria must be met

Slip-critical/friction connection

Which of the following is a type of connection designed for fatigue loading and for connections subject to direct tension?

Major structural connections.

High-strength bolts are primarily used in

.30

typical range of the ratio of transverse to longitudinal strain for most common metals in the elastic range

Shear stress and deflection.

Once a steel section is tentatively selected for a beam, what are the two main structural requirements that must be checked according to the module?

Truss members

L-Shapes (Angles) are mainly utilized as which type of structural members according to the module?

Stress increases due to dislocation interactions and strain hardening

When analyzing strain hardening in a tensile test, which of the following correctly describes the relationship between true stress and true strain beyond the yield point?

Carbon Steel

A class of structural steel that can yield strength of 36-50 ksi (A36-A50).

Maximum Moment.

When designing a steel beam using AISC procedures, what is the first structural requirement typically determined after calculating the applied loads?

Choose the lightest of all possible sections that meet the requirement.

From the Steel Tables, how should a designer typically select a steel section that meets the required Section Modulus?

Over 930°C

At what temperature is raw steel (steel billets) typically roll-pressed during the hot rolling process?

50 to 75 ksi

What is the yield strength range of Heat Treated Carbon/HSLA Steel?