TIME AND COST STUDY ON COLD-FORMED
STEEL AND REINFORCED
CONCRETE CONSTRUCTION
COMPARISON
-A
HU WET KJET
in fulfillment
A thesis submitted
of the requirements for the degree of Master of Engineering
Faculty of Engineering
UNIVERSITI MALAYSIA SARAWAK
2008
For my beloved parents.
11
ACKNOWLEDGEMENTS
Hereby,
I wish to attribute
and co-supervisor,
during
I would
Associated
gratitude
Professor
Dr. Ng Chee Khoon on their
and advice
guidance
this research.
also like to express
advice, guidance
the following
1. Multi
2.
greatest
Ms. Ting Sim Nee
to my thesis supervisor,
my appreciation
and encouragement
companies
for their
to those who assisted
me in every aspect,
to make this thesis a success. I would like to thank
assistance
and cooperation.
Resources Group of Company
EcoSteel Sdn Bhd
3. Sarawak Housing Development Corporation, and
4. All the companies which provided information
during interview
session
Lastly, I would like to thank everyone who had helped me in completing
thesis, for their meaningful information
and substantial moral support.
111
this master
ABSTRACT
Nowadays,
countries
in building
especially
is still
construction
industry,
as a new
is
steel
method,
construction
There are some barriers
barrier
is market
that limit
design
to cold-formed
steel. Thirdly,
formed
steel construction
in time
familiar
traditional
exposure
The aim
Malaysian
with
the market
experience
cold-formed
favoured
a relatively
expensive
have limited
knowledge
lacks of information
local market
The
steel in Malaysia.
is
steel
and architects
engineers
about the cold-
So, local market
was
still
the
prefers
project,
cold-formed
on the
practice
of site engineers.
material
on real
life
of low-cost
cost for the project
The design of cold-formed
of the reinforced
carried
out based on a pilot
derived
from the sizes of development
project
suppliers
of project
was conducted
on
and architects
steel.
conducted
and the total
2 principles
time and cost. An interview
developers,
method,
construction
done
with
was
in
steel
use of cold-formed
traditional
with
A comparison
based
Based
Sarawak.
the potential
as compared
contractors,
towards
research
on the dimensions
is to study
industry
engineers,
the project
complete
In
construction.
is still greatly
construction
and cost aspects.
for a successful
reactions
This
in
research
construction.
criteria
consulting
project
of this
concrete
management
construction
method.
construction
reinforced
concrete
truss
roof
the usage of cold-formed
that
perception
the local
Secondly,
material.
reinforced
in
seen
commonly
In local
method.
construction
steel
cold-formed
industry.
by local construction
first
only
in some developed
common
in Malaysia,
However,
construction.
considered
cold-formed
traditional
steel is quite
the usage of cold-formed
concrete
Costing
for both cold-formed
project.
IV
housing
were
Time
structure
concrete
the
project,
estimated
framed
steel
structure.
in Kuching.
reinforced
time
based
structure
on the
was based
and cost estimates
and time
estimation
steel and reinforced
to
were
could
be
concrete
Comparative
relatively
material
than
shorter
analysis
than
reinforced
cost for the cold-formed
the reinforced
for
machinery
concrete
the
showed that the time for cold-formed
the
construction.
construction
concrete
Generally,
steel
the
method.
construction
total
than the reinforced
V
From
construction.
steel construction
construction
cold-formed
was still higher
concrete
method
construction
cost
labour,
cost
cost of plant
than
cheaper
of
concrete construction.
aspect,
was
the
more expensive
was slightly
However,
are
steel construction
the
and
reinforced
cold-formed
steel
ABSTRAK
Gelek Sejuk dalam
Keluli
Struktur
"Pengunaan
di
umum
ini
sebagai
keluli
tempatan,
pembinaan
kekuda
bumbung
pembinaan
konkrit
bertulang
pembinaan
bagi
cara
gelek
baru
hanya
bangunan.
banyak
masih
gelek sejuk adalah
pembinaan.
Tetapi,
di Malaysia.
Dalam
dalam
bidang
industri
pembinaan
sejuk
sesebuah
keluli
rangka
dalam
terutamanya
dianggap
masih
pembinaan
dalam
maju
negara-negara
pembinaan
industri
kegunaan
masa kini,
Pada
dan Kos"
Masa
Kajian
-
Tempatan
Pembinaan
Industri
digunakan
Cara
digunakan
tradisional,
pembinaan
dalam
industri
pembinaan
tempatan.
beberapa
Terdapat
Malaysia.
Halangan
maklumat
aspek
terhad
yang
tentang
kos.
Jadi,
Ketiga,
ini.
tempatan
pasaran
tempatan
tidak
ada
gelek sejuk dalam
keluli
banyak
masih
mempunyai
tempatan
pasaran
pembinaan
persembahan
harga keluli
menganggap
pereka dan arkitek
Kedua, jurutera
pembinaan
sentiasa
gelek sejuk di
menggunakan
cara
tradisional.
pembinaan
Tujuan
utama
gelek sejuk
dalam
pembinaan
konkrit
dibandingkan.
industri
2 aspek projek
ini
bahan
terhadap
dijalankan
mentah
i. e. masa
dengan
dan
jurutera
arkitek
kos telah
dan
pereka,
telah
keluli
tradisional,
cara pembinaan
pengurusan,
tem. uduga
perbandingan,
pembekal
dengan
pengunaan
potensi
membandingkan
Malaysia
pembinaan
bertulang.
reaksi pasaran
Penyelidikan
ini ialah
penyelidikan
Sebelum
tempatan,
mengetahui
tentang
mencukupi
dan
masa
pembina
pertama
tempatan
keluli
pengunaan
yang menghadkan
ialah pasaran
lebih tinggi.
gelek sejuk adalah
pengetahuan
halangan
kontraktor,
diadakan
untuk
sebenar
konkrit
keluli gelek sejuk.
dengan
menggunakan
projek
bertulang di Sarawak. Dengan project rumah kos rendah ini, masa untuk pembinaan
dan kos untuk projek ini dapat dijangka
keluli
gelek sejuk
direka
mengikut
dengan pengalaman jurutera.
dimensi
vi
yang
sama
dengan
Struktur
rangka
struktur
konkrit
bertulang.
gelek
Jangkaan
berlainan
kos penyewaan
sejuk adalah
untuk
adalah
untuk
konkrit
pembinaan
bertulang.
ini, jangkaan
Secara
lebih tinggi
dan
masa
kos bahan
termasuk
pertama
keluli
saiz projek
yang
projek
kos untuk
kos pemasangan,
mentah,
pembinaan
Tetapi
daripada
konkrit
pembinaan
keluli
gelek
sejuk
bagi kos pekerja
lebih
gelek sejuk adalah
keseluruhan,
ini, masa pembinaan
penyelidikan
daripada
bertulang.
keluli
berdasarkan
kos
kos
dan
dan
rekaan.
mesin
alat
lebih pendek
mentah
pembinaan
Selain
kepada keputusan
Merujuk
dibuat
kos projek
Kos tersebut
dijalankan.
pekerja,
bahan
masa
di Sarawak.
sejuk
dan
jumlah
pembinaan
kos projek
konkrit
vii
bertulang.
adalah
untuk
Bagi
lebih
rendah
bagi pembinaan
bertulang.
gelek
aspek kos, kos
daripada
tinggi
dan kos penyewaan
daripada
keluli
dn
mesin
alat
pembinaan
keluli
konkrit
gelek
sejuk
TABLE
OF CONTENTS
Page
CONTENT
TITLE
i
PAGE
DEDICATION
11
ACKNOWLEDGEMENT
iii
ABSTRACT
iv
TABLE
OF CONTENTS
viii
LIST OF TABLES
xii
LIST OF FIGURES
xv
Chapter
1
INTRODUCTION
1.1
General
1
1.2
What is Cold-Formed Steel
2
1.2.1 Common
Shapes of Session
4
6
1.2.2 Connections
1.2.3 Common
7
Applications
10
1.2.4 Code/Regulatory
1.2.5 Properties
1.3
of Cold-Formed
Steel
11
1.2.6 Installation
11
1.2.7 Fire Protection
12
Aim and Objectives
12
viii
Chapter
2
LITERATURE
2.1
2.2
REVIEW
General
15
2.1.1 Time
17
2.1.2 Cost
18
2.1.3 Quality
19
Comparison
between
Cold-Formed
Steel and
21
other materials
21
2.2.1 Cold-Formed
Steel and Wood
2.2.2 Cold-Formed
Steel and Hot-Rolled
2.2.3 Cold-Formed
Steel and Reinforced
Steel
29
31
Concrete
2.3
Chapter
3
33
Case Study
METHODOLOGY
3.1
General
3.2
Information
39
39
Sources
39
Information
3.2.1 Background
40
3.2.2 Interview
3.3
Data Collection
41
and Analysis
41
3.3.1 Case Study
3.3.2 Cold-Formed
Steel Framing
Design
43
3.3.3 Assumptions
3.3.4 Time, Cost, and Quality
3.3.5 Comparison
43
Analysis
3.3.6 Project Cost Projection
ix
Analysis
50
54
55
Chapter
4
RESULTS
4.1
General
4.2
Project
4.3
Results
56
62
Description
Steel
Cold-Formed
of
Framing
63
Construction
4.4
4.5
Chapter
5
4.3.1 Time
64
4.3.2 Cost
71
Result for Reinforced
Concrete
Construction
85
4.4.1 Time
85
4.4.2 Cost
92
Quality
111
DISCUSSIONS
5.1
Time
116
5.2
Cost
120
5.2.1 Total Construction
121
Cost
5.2.4 Installation
123
Cost
5.2.5 Plant and Machinery
5.3
120
120
Cost
5.2.2 Material
5.2.3 Labour
Cost
Costs
123
5.2.6 Design Charges
124
5.2.7 Other Costs
124
5.2.8 Cost Projection
125
Quality
127
X
Chapter 6
130
CONCLUSIONS
REFERENCES
138
APPENDICES
143
Appendix A-
Questionnaire
Appendix B-
Drawings
Appendix
C-
Cold-Formed
Appendix
D-
Bondek
Steel Design
Design
Appendix E-
Labour Daily Working Schedule
Appendix F-
Plant and Machinery Rental Duration
Appendix
G-
Grant
Chart
Format
Time
Schedule
(10 houses)
xi
for CFS and RC
LIST OF TABLES
Page
Table
2.1
2.2
2.3
2.4
3.1
3.2
3.3
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
4.15
4.16
4.17
4.18
4.19
4.20
4.21
4.22
4.23
4.24
4.25
4.26
4.27
4.28
4.29
4.30
4.31
Summary of Blower Door Tests
Comparison of Steel and Wood Framing
Light Steel Building versus Reinforced Concrete Building
Cost Comparison between Light Steel Building and Reinforced Concrete
Building
Material Pricing Schedule
Labour Wage Rates Schedule
Machinery Rental Rate Schedule
Steel Structure (1 house)
Time Schedule for Cold-Formed
Construction
Steel Structure (10 houses)
Time Schedule for Cold-Formed
Construction
Time Schedule for Cold-Formed Steel Structure (20 houses)
Construction
Time Schedule for Cold-Formed Steel Structure (60 houses)
Construction
Time Schedule for Cold-Formed Steel Structure (120 houses)
Construction
Steel Structure (180 houses)
Time Schedule for Cold-Formed
Construction
Steel Structure (240 houses)
Time Schedule for Cold-Formed
Construction
Material Cost Schedule for Cold-Formed Steel Structure (1 house)
Material Cost Schedule for Cold-Formed Steel Structure (10 houses)
Material Cost Schedule for Cold-Formed Steel Structure (20 houses)
Material Cost Schedule for Cold-Formed Steel Structure (60 houses)
Material Cost Schedule for Cold-Formed Steel Structure (120 houses)
Material Cost Schedule for Cold-Formed Steel Structure (180 houses)
Material Cost Schedule for Cold-Formed Steel Structure (240 houses)
Cost Schedule for Cold-Formed Steel Structure (1 house)
Installation
Cost Schedule for Cold-Formed Steel Structure (10 houses)
Installation
Cost Schedule for Cold-Formed Steel Structure (20 houses)
Installation
Cost Schedule for Cold-Formed Steel Structure (60 houses)
Installation
Cost Schedule for Cold-Formed Steel Structure (120 houses)
Installation
Cost Schedule for Cold-Formed Steel Structure (180 houses)
Installation
Cost Schedule for Cold-Formed Steel Structure (240 houses)
Installation
Labour Cost Schedule for Cold-Formed Steel Structure (1 house)
Labour Cost Schedule for Cold-Formed Steel Structure (10 houses)
Labour Cost Schedule for Cold-Formed Steel Structure (20 houses)
Labour Cost Schedule for Cold-Formed Steel Structure (60 houses)
Labour Cost Schedule for Cold-Formed Steel Structure (120 houses)
Labour Cost Schedule for Cold-Formed Steel Structure (180 houses)
Labour Cost Schedule for Cold-Formed Steel Structure (240 houses)
Steel Structure
Plant and Machinery Cost Schedule for Cold-Formed
(1 house)
Steel Structure
Cost Schedule for Cold-Formed
Plant and Machinery
(10 houses)
Steel Structure
Plant and Machinery Cost Schedule for Cold-Formed
(20 houses)
4.32
Plant and Machinery Cost Schedule for Cold-Formed Steel Structure
(60 houses)
4.33
Plant and Machinery
(120 houses)
Plant and Machinery
(180 houses)
Plant and Machinery
(240 houses)
4.34
4.35
4.36 Total Construction
(1 house)
4.37
Total Construction
(10 houses)
4.38 Total Construction
(20 houses)
4.39 Total Construction
26
27
31
33
45
46
47
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
78
78
79
79
79
79
79
80
80
80
80
81
81
81
82
82
82
Cost Schedule
for Cold-Formed
Steel Structure
83
Cost Schedule
for Cold-Formed
Steel Structure
83
Cost Schedule
for Cold-Formed
Steel Structure
83
Cost Schedule for Cold-Formed Steel Structure
Cost Schedule for Cold-Formed
Steel Structure
84
84
Cost Schedule for Cold-Formed Steel Structure
84
Cost Schedule for Cold-Formed Steel Structure
84
xii
(60 houses)
4.40
4.41
4.42
4.43
4.44
4.45
4.46
4.47
4.48
4.49
4.50
4.51
4.52
4.53
4.54
4.55
4.56
4.57
4.58
4.59
4.60
4.61
4.62
4.63
4.64
4.65
4.66
4.67
4.68
4.69
4.70
4.71
4.72
4.73
4.74
4.75
4.76
4.77
4.78
5.1
5.2
5.3
Cost Schedule for Cold-Formed Steel Structure
Total Construction
(120 houses)
Cost Schedule for Cold-Formed Steel Structure
Total Construction
(180 houses)
Cost Schedule for Cold-Formed Steel Structure
Total Construction
(240 houses)
Time Schedule for Reinforced Concrete Structure (1 house)
Construction
Time Schedule for Reinforced Concrete Structure (10 houses)
Construction
Time Schedule for Reinforced Concrete Structure (20 houses)
Construction
Time Schedule for Reinforced Concrete Structure (60 houses)
Construction
Time Schedule for Reinforced Concrete Structure (120 houses)
Construction
Time Schedule for Reinforced Concrete Structure (180 houses)
Construction
Time Schedule for Reinforced Concrete Structure (240 houses)
Construction
Material Cost Schedule for Reinforced Concrete Structure (1 house)
Material Cost Schedule for Reinforced Concrete Structure (10 houses)
Material Cost Schedule for Reinforced Concrete Structure (20 houses)
Material Cost Schedule for Reinforced Concrete Structure (60 houses)
Material Cost Schedule for Reinforced Concrete Structure (120 houses)
Material Cost Schedule for Reinforced Concrete Structure (180 houses)
Material Cost Schedule for Reinforced Concrete Structure (240 houses)
Cost Schedule for Reinforced Concrete Structure
Installation
Labour Cost Schedule for Reinforced Concrete Structure (1 house)
Labour Cost Schedule for Reinforced Concrete Structure (10 houses)
Labour Cost Schedule for Reinforced Concrete Structure (20 houses)
Labour Cost Schedule for Reinforced Concrete Structure (60 houses)
Labour Cost Schedule for Reinforced Concrete Structure (120 houses)
Labour Cost Schedule for Reinforced Concrete Structure (180 houses)
Labour Cost Schedule for Reinforced Concrete Structure (240 houses)
Plant and Machinery Cost Schedule for Reinforced Concrete Structure
(1 house)
Cost Schedule for Reinforced Concrete Structure
Plant and Machinery
(10 houses)
Plant and Machinery Cost Schedule for Reinforced Concrete Structure
(20 houses)
Plant and Machinery Cost Schedule for Reinforced Concrete Structure
(60 houses)
Plant and Machinery Cost Schedule for Reinforced Concrete Structure
(120 houses)
Cost Schedule for Reinforced Concrete Structure
Plant and Machinery
(180 houses)
Plant and Machinery Cost Schedule for Reinforced Concrete Structure
(240 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(1 house)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(10 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(20 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(60 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(120 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(180 houses)
Cost Schedule for Reinforced Concrete Structure
Total Construction
(240 houses)
Total Construction Time for Cold-Formed Steel Structure and
Reinforced Concrete Structure
Construction End Date for Cold-Formed Steel Structure and Reinforced
Concrete Structure
Total Construction Cost for Cold-Formed Steel Structure and Reinforced
xiii
84
85
85
85
86
87
88
89
90
91
92
94
96
97
99
101
102
104
104
105
105
105
106
106
106
107
107
108
108
108
109
109
109
110
110
110
110
111
111
116
116
120
5.4
5.5
5.6
5.7
5.8
5.9
6.1
6.2
6.3
Concrete Structure
Total Construction Cost per Unit for Cold-Formed Steel Structure and
Reinforced Concrete Structure
Material Cost for Cold-Formed Steel Structure and Reinforced Concrete
Structure
Labour Cost for Cold-Formed Steel Structure and Reinforced Concrete
Structure
Installation Cost for Cold-Formed Steel Structure and Reinforced
Concrete Structure
Plant and Machinery Cost for Cold-Formed Steel Structure
Reinforced Concrete Structure
Comparison of CFS and RC on Percentage for the Cost
Earlier Completion Time for Cold-formed Steel Construction
With Reinforced Concrete Construction
and
Compared
Total Construction Cost for Cold-Formed Steel Structure and Reinforced
Concrete Structure
Percentage of Material Cost for Cold-Formed Steel Structure and Reinforced
Concrete Structure
xiv
120
121
122
123
123
126
130
132
132
LIST OF FIGURES
Page
Figure
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.1
2.2
Roll Forming Machine
Cold-Roll Forming
Basic Shapes of Cold-Formed Steel
Common Shapes of Cold-Formed Steel Sections
Framing
Cold-Formed Sections Used in Structural
Decks, Panels and Corrugated Sheets
Wall framing
Whole House Framing
Storage Racking
by Application
U. S. Houses Using Steel Framing
1997-1999
for
Colorbond®
Steel
Roofing
Low Cost Housing in Australia
using
and Walling
3
4
5
5
6
6
7
7
10
16
34
2.3
The Coddington House at Bayview features LYSAGHT MINI ORB®
Wall Cladding in COLORBOND® Steel
35
2.4
2.5
2.6
2.7
2.8
4.1
4.2
4.3
4.4
5.1
Steel
Wall Cladding in COLORBOND®
Steel
Wall Cladding in COLORBOND®
Home in Corio Bay Geelong Victoria
Steel Framed House
Lightweight
Steel Framed House
Lightweight
Steel in the Local Building Industry
The Usage of Cold-Formed
Cold-Formed Steel Roofing
Important
Criteria that Industry Considered
Construction
Industry
in
Malaysian
Suitability
Cold-Formed
Steel
of
in Different
Total Construction
Time for CFS and RC Construction
Scale
Construction
Cost Difference per Unit of House
35
35
36
37
37
56
57
59
60
117
5.2
xv
125
CHAPTER
1
INTRODUCTION
1.1 GENERAL
industry
The construction
one should
in
consider
in the
evolution
human
chain.
cold-formed
products,
as the fourth
beauty
and
economy
in construction
century
of
along
has been
B. C, iron
bearing
to PATH
walls
and curtain
steel only attracts
in residential
to design
the
cold formed
(2002), steel framing
structures
could
buildings
More
with
cold-formed
provide
and more
steel
a relatively
for many
and various
stable
floor and roof
wall,
main
However,
years.
architects
as the
more
towers
storage
had been used in interior
for use in load bearing
recently.
to Yu (1997),
and bridge construction,
grain bins, transmission
in commercial
in some
common
and Japan. According
Australia
the attention
construction
steel
has been quite
building
in
used
facilities,
drainage
According
types of equipment.
cold-formed
were widely
steel members
highway
racks,
because
As early
utility,
is a basic ingredient
creation,
States of America,
such as United
countries
prefer
quality,
steel in construction
The use of cold-formed
framing
the
aspects that
is one of the important
of construction
for more
look forward
in China.
discovered
non-load
a new era and one should
to fulfill
order
Steel, a modern
construction.
the way
The material
structures.
advanced
has entered
and engineers
materials.
framework
It
is
for
a
structure.
According to Wagner (2003), Melbourne's Colonial Stadium in Australia
a great steel structure.
The most challenging
feature for this well-built
is one of
stadium
in
The
300
is
The
the
is
the roof.
m.
nearly
roof span
main arch of
engineering perspective
design of the long span roof structure was made of extensive use of cold formed tabular
had
thorough
experimental
undergone
members which
I
testings and research. The main
arch
has
the
a structural
roof
of
efficient
extremely
frequent
experience
earthquakes.
because it has higher
locations
it
can resist
the
natural
lightness,
strength,
and installation,
erection
that
industry
would
and quality
formed
advantages.
method
Usually,
construction
hardly
One
can
stage.
cold-formed
steel truss
Thus
during
such
structures
such as timber
of
fast and easy
there are still other barriers
is the cost. The construction
only if they manage
see many
in terms
advantages
is how the thermal
The second barrier
than lumber.
and handling.
barrier
Malaysia,
In
homes.
in
steel affects energy use
the very beginning
around.
The primary
building
the
new
use
Steel is used in such
and mass production,
framing,
steel
of cold-formed
and
to other materials
the following
ease of prefabrication
its usage in construction.
limit
offer
in
transportation
and economy
Besides the availability
such as hurricanes
strength
residential
to Yu (1997), as compared
stiffness,
disasters
bending
upon
exerted
that
found in Hawaii.
and greater
steel members
cold-formed
and concrete,
forces
destructive
According
disasters.
damage or natural
tensile
locations
used in geographical
is more commonly
homes are commonly
Steel framed
an
represents
steel for such a span.
related
weather
of only
steel weight
use of cold-formed
steel framing
Currently,
85 kg/m2. This
to exhibit
of cold-
conductivity
use of cold-formed
steel is still
element
that
at
buildings
steel framed
cold-formed
is the most common
clear cost
is used in
here.
1.2 What is Cold-Formed
For building constructions,
Steel ?
there are two main types of structural
steels: hot-rolled steel
Structures
Steel
Homes
Sunway
According
to
and cold-formed steel.
formed
temperature.
an
elevated
at
steel shapes are
are formed at room temperature.
plate, sheet and strip material.
(2005), hot-rolled
For cold-formed steel, the shapes
The cold-formed steel is generally shaped from steel
to Chen (NA), the manufacturing
According
involves forming the material by either press-braking
2
process
or cold roll forming to achieve the
floor
and
roof
steel
desired shape. Examples of the cold-formed steel are corrugated
decks, steel wall panels, storage racks and steel wall studs.
Press-braking
Cold rolling-forming
wall
panels.
method
method
is often used to produce
is the most widely
It is also used for production
hat
sections.
and
Sections
can usually
small
used method
of structural
quantity
of simple
in producing
components
shapes.
roof, floor and
Zees,
Cees,
such as
be made from sheets up to 60 inches (1.5 m) wide
long.
feet
(1,000
3,000
from
than
m)
coils more
and
During
rolls,
cold rolled
each of which
works
simple section may require
forming,
sheet stock is fed longitudinally
the sheet progressively
until
of material
formed
can generally
forming
duty
Heavy
(0.79
inches
0.312
cold
mm).
mm) to
mills
thick.
Figure 1.1: Roll Forming Machine
3
a series of
the desired
it reaches
but
few
a complex
as six pairs of roll,
as
The
30.
thickness
24
to
as
many
of an inch (19mm)
through
shape. A
shape can require
as
range from 0.004 (0.10
can handle
3/4
to
steel up
Figure 1.2: Cold-Roll Forming
(Source: Chen, NA. An Overview
Cold-formed
a number
of useful
can be produced
tension
equal
material
structural
It is a strong
1.2.1 Common
loads, and is fully
shapes
shaped
loading
member.
aspects, which
precisely.
member
that
It carries
both
is approximately
deformation
Its
recovered
on removal
at normal
temperature.
is directly
of the loading.
cold-formed
are used in many
steel sections
the particular
application.
In building
industries
purpose,
There
Z
C
the
the
shapes.
are a whole range of variety
and
sections are
those with
edge lips, internal
Other section shapes are the "top-hat"
stiffeners
stiffeners
because unstiffened
compression
inefficient.
However, a highly
stiffened
the most
of these
section and the modified I section. The
wide thin
lips and
plates are not able to resist
the use of steel in the section becomes
and consequently
significant
and
bends
in the webs.
and
sections can also be joined together to form compound members. The additional
are included
It will
of sections
to suit
basic shapes, including
exhibits
material
and reliable
of tension
strength
of compression
strength
to Corus (2003),
are specially
common
crushing
in many
and it can be fabricated
loads. The yield
stable under long-term
also remain
According
characteristics.
to meet specifications
to applied
proportioned
Steel Structures)
steel is an ideal structural
and compression
to the
of Cold-Formed
section is not easy to form and is often not
4
between
Therefore,
its
from
the
a
compromise
connections.
point of view of
practicable
section efficiency and practicability
is often necessary.
Figure 1.3: Basic Shapes of Cold-Formed Steel
(Source: NAHB, NA. Designing Homes Using Cold-Formed Steel)
Figure 1.4: Common Shapes of Cold-Formed
(Source: Chen, NA. An Overview of Cold-Formed
5
Steel Sections
Steel Structures)
IL
CEýZ ILLJF.
I
(b)
(a)
J-1
tcf
L
(i)
I
tdt
-V
(j)
1.5: Cold-Formed
Figure
Inur1
t"" w"`"'1
L...JA.
_J
4 k)
vL
tmi
(I)
(r)
(h}
(ý4
ffi
(q)
lp)
toi
(fY
iel
(g)
(n)
(t)
Sections Used in Structural
(c)
(b)
(a)
Framing
Roof decks
tfý
{e}
(d)
Lo1,g- span roof decks
TL
LJUJ
(1)
(i)
(h)
Floor and roof panels
(g}
(1G)
Curtain wall panels
Figure
i. l U LJ 1J
(1)
Ribbed panels
(m)
Corrugated sheets
1.6: Decks, Panels and Corrugated
Sheets
1.2.2 Connections
According to Yu (1997), welds, bolts, screws, rivets, and other special devices such as
The
for
connections.
steel
cold-formed
metal stitching and adhesives are generally used
AISI Specification
bolted
for
design
the
connections,
welded
provisions
contains only
connections, and screw connections.
6
1.2.3 Common
Applications
to Corus Construction
According
cold-formed
Centre
(2003) and Chen (NA), the structural
these features
sections that utilize
usage of
are as follows:
(a) Roof and Wall Members
Traditionally,
rails
to support
in industrial
the cladding
the Z section (and its variants),
improve
use of cold-formed
predominant
the efficiency
made for eaves members
which
of the members
steel has been as purlins
type buildings.
facilitates
These are generally
incorporation
in multi-span
applications.
Special
Figure 1.7: Wall Framing
(Source: AISI,
1.8: Whole House Framing
NA. Cold-Formed
7
based on
of sleeves and overlaps
and so on.
Figure
and side
Steel Design Gallery)
shapes
to
are
(b) Steel Framing
An increasing
market
for
and panels
walls
in
light
industrial
buildings.
framing
system
column framing
commercial
to Gaylord
to replace
members
is the site-assembled
steel sections
and roofs, and stand-alone
and
According
for cold-formed
buildings.
buildings
and
(1990), cold-formed
the use of lumber
and other structural
in
This approach
mezzanine
frames
has been used
floors
of existing
steel is also used in residential
in the individual
beams,
joists,
steel
studs,
components.
(c) Wall Partitions
A special application
for very light sections is used in conjunction
board panels in stud wall partitioning
with plaster
to form a thin robust wall.
(d) Large Panels for Housing
Storey-high panels can be factory-built
and assembled into housing units on site.
This is an extension of the approach used for timber framing.
(e) Lintels
A significant
lintels
formed
for
is
as
cold-formed sections
specially
market
over
doors and windows in low rise masonry walls. These products are often powder coated
for extra corrosion protection.
(f) Floor
Joist
Cold-formed sections may be used as an alternative
for timber joists in floors of
modest span in domestic and small commercial buildings.
(g) Modular
Frames
A prefabricated
for Commercial
modular framing
Buildings
and panel system using cold-formed channels
had
been
developed
lattice
for use in buildings up to 4-storied height. Although
joists
and
8
developed for commercial building, this modular system has broad application
primarily
in the areas as educational and apartment buildings.
(h) Trusses
(i) Space Frames
(j) Curtain
Walling
A modern
in standard
glazing
application
glazing
framing
steel buildings,
systems,
to multi-storied
and as mullions
mullions
and transoms
in standard
and transoms
systems.
Buildings
(k) Prefabricated
The transportable
a common
prefabricated
(1) Frameless
application
that
prefabricated
use of cold-formed
Steel
steel. Other
applications
site hut) is
are used as
buildings.
Buildings
plates,
barrel
have been developed
beams and which rely partly
(m) Storage
building unit (such as the ubiquitous
"toilet pod" units in multi-storied
Steel folded
systems
in cladding
vaults
and truncated
as so-called
on a "stressed
frameless
pyramid
roofs are examples
buildings
of
(i. e. those without
skin" action).
Racking
buildings
are made
steel sections, mostly consist of special clip attachments,
bolted
or
Storage racking systems used in warehouses and industrial
from cold-formed
joints for easy assembly.
9