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Building construction Materials use and behavior in fire > Metals > Flashcards

Flashcards in Metals Deck (9)
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1
Q

What only metals are used in construction to carry load

A

Iron

Steel

2
Q

Unprotected metal surfaces may

constitute a serious risk in a fire because

A

Expansion

conduction

3
Q

Structural steel,

for example, loses two-thirds of its strength at what temp, and then will…

A

about 600 degrees c

expand, bend , twist

4
Q

There are two distinct ways in which steel is used

in building construction

A

structural material or

reinforcement in concrete

5
Q

How does steels tensile strength relate to its compressive strength

A

Steel’s compressive strength is equal to
its tensile strength. Its shear strength is about 75%
of its tensile strength

6
Q

List some insulating materials for steel

A
Brick
Concrete
Insulating boards
Sprayed coatings
intumescent paints
7
Q

Discuss the risk of expanding heated metal beams

A

it is built into a loadbearing wall, such expansion
may cause collapse.
In a framed building, the failure
of a single beam or column is unlikely to cause
more than a local collapse

8
Q

Increasing use is being made of aluminium and its
alloys for structural and cladding members and
this has created new fire problems. The advantages
of using aluminium alloy in buildings are

A

Resistance to corrosion;
A reduction in the weight of the structure;
Ease of handling and working; and
The high strength to weight ratio

9
Q

The disadvantages of aluminium are

A

0 The very rapid loss of strength in fire
(stability is affected at 100°C to 225°C);
0 The high expansion rate (approximately twice
that of steel);
0 Its very low melting point (pure aluminium
melts at 660°C).