ct3 group project

1. 1
School of Architecture, Building and Design
Bachelor of Quantity Surveying (Honours)
Construction Technology 3[QSB 2514/BLD 60304]
Group Assignment
Name : Tan Shen Sin 0324602
Thasia 0329051
Wong Sher Sheng 0329950
Topic :Steel Framing System
[ Cold-Form Structures + Composite Floor Slab ]
Lecturer : Mr Chai Voon Chiet

2. 2
Table of content Pages
Introduction of Steel framing system 3
Cold form structures 4-7
Composite floor slab 8
Installation of compositeslab 9
Advantages & disadvantages of cold form structures 10-11
Advantages & disadvantages of compositeslab 12-13
Case study 14-18
Reference 19

3. 3
Steel framing system
Introduction
Steel was first produced in the Middle Ages, but it was only used for building structural
purposes until just over a century ago. Today many remarkable structures demonstrate the
possibilities of using this material in their appearances. Among which include the Eiffel Tower.
The strength-to-volume ratio, the wide range of possible applications, the reliability of the
material and the ability to give shape to nearly all architectural wishes are the reasons to choose
this material for the main structure of a building.
For the structural framing purposes, the steel sections are normally used for beams,
columns and roof truss constructions. In Malaysia, these steel sections are manufactured to
specific British Standards. These sections could be either hot-rolled or welded. Universal Beam
(UB) is a common section used for structural beam, while Universal Column (UC) is a common
section for structural column. The main difference between the UB and UC is the depth (D) to
width (B) ratio of the section.
Houses that adopted Steel Framing System

4. 4
Cold form structure
Cold-formed steel framing is made from strips of structural quality sheet steel that are fed
through roll forming machines with a series of dies that progressively shape the steel into C-
shaped sections, or formed into a variety of other shapes, including “U”, “Z”, and even hat-
shaped sections. Cold-formed steel framing members can be formed from a wide range of
material thickness that enables them to meet the requirements of nearly all structural and non-
structural applications.
Manufacturing process
1. Cold-formed steel starts with the production of raw steel, which is made by combining
iron ore or steel scrap with small amounts of carbon in a Basic Oxygen Furnace (BOF) or
Electric Arc Furnace (EAF)

5. 5
2. Molten steel is poured into slabs that are reduced into thinner strips of steel, called “hot
band.” Increasingly, steel mills are employing a new, very efficient process called direct
reduction to make “hot band.”
3. In the steel finishing process, the hot band is reduced once again into “cold rolled
steel.” A protective coating of zinc is then added through the galvanization process. The
final product is called a “coil.”

6. 6
4. To convert coils into cold-formed steel framing members, they are first slit into widths
that match the intended dimensions of the final product.
5. The slit coils of cold-formed steel are formed into C-sections and other shapes usually by
roll forming the steel through a series of dies. Penetrations for plumbing and electrical
runs are also punched at pre-determined locations, helping reduce installation times. No
heat is required to form the shapes and thus the name cold-formed steel.

7. 7
6. The cold-formed steel framing materials are then either used to build wall and floor
panels, and roof trusses, or delivered to the job site in bundles.

8. 8
Composite floor slab
Composite slabs comprise reinforced concrete cast on top of profiled steel decking. This acts as
formwork during construction and external reinforcement at the final stage. The decking can be
either re-entrant or trapezoidal. Trapezoidal decking may be over 200 mm deep which known as
deep decking. Additional reinforcing bars may be placed in the decking troughs, particularly for
deep decking. They are sometimes required in shallow decking when heavy loads are combined
with high periods of fire resistance.
Trapezoidal decking Re-entrant decking
Re-entrant or trapezoidal decking of 50 to 60 mm depth can span around 3 m unpropped, 80 mm
deep trapezoidal profiles can span up to around 4.5 m unpropped, and deep decking can achieve
around 6 m. Overall slab depths range from 130 mm upwards.

9. 9
Installation of Composite Slab
1. Installation of decking
First, the contractor will place metal decking on the structural steel at predetermined
points in the erection sequences. Powder actuated tools can be used as an alternative of
welding to attach metal decking to the structural steel. A nail-like fastener is driven
through the metal deck into the steel beam.
2. Shear connectors
Installing shear connector to create a strong bond between the steel beam and the
concrete floor slab which is poured on top of the metal decking. The tip of the shear
connector may be placed in a ceramic ferrule to retain the weld during the welding
process.
The ferrules are removed before the concrete is poured.
3. Installation of concrete
Lastly, after the decking has been installed, concrete contractor will cast the concrete,
usually by pumping method on top of the composite metal decking, shear connectors, and
welded wire fabric or rebar grid.

10. 10
Advantages of cold form structures
 Strength
Steel has the highest strength to weight ratio of any building material. The strength of
cold-formed steel provides architects with greater flexibility.
 Durable
Steel can last hundreds of years without any deterioration due to the fact that steel is
inorganic, and thus impervious to termites and rot. A protective layer is used to provide
high resistance to corrosion.
 Non-combustible
Steel will not contribute to the spread of a fire. Because of this, cold-formed steel projects
can easily be designed to meet code fire rating requirements. This gives lower costs and
broader coverage for many types of construction insurance.
 Sustainable
Steel is the only building material that is infinitely recyclable. As a recognized green
building material, cold-formed steel framing projects can earn credits for green building
ratings such as LEED.
 Cost-effective
By helping to minimize the risk, the use of cold-formed steel results in lower insurance
costs for builders and owners. The cold-formed steel construction methods allowing
builders to complete the projects months faster than with other framing materials due to
shorter construction cycles,
 Lightweight
Cold-formed steel are usually lightweight, making it easy to transport and erect

11. 11
Disadvantages of cold-form structure
 Low fire resistance
Even though light gauge steel won’t burn, it can still lose strength in a fire.
 Unit price
Cold rolling process is expensive compare to hot-rolled system due to the equipment and
labour cost in production.
 Careful requirement
Careful treatment is required when assembling as it can caused buckling as cold-formed
steel is not as strong in physical structure compare to hot-rolled steel.
 Difficult connecting
Due to the thinness of cold-form steel, connecting steel section must be done in caution,
especially for welded joints.
 Thermal and sound insulation
It has low thermal and sound insulation. Steel also transmit sound more readily than
wood therefore installing internal soundproofing may be required.
 Rusting
Steel is subject to rusting due to moisture or water.

12. 12
Advantages of composite slab
 Versatility
Composite slab can be adapted to many practical cases and a multitude of solutions.
 Resistance weight ratio
Have a great resistance with less weight, thus enabling a global reduction of the
structure’s weight. The minimum slab edge measures is only 12 cm.
 Quick installation
The time taken for installation is shorter than timber flooring. The absence of props
means that more than one floor can be concreted at the same time, thus reducing
construction time per floor.
 Cost reduction
Cost reduction in both in terms of labour costs and material cost as there is no need for
props, and less concrete is used.
 Safe
The concrete slab is being poured progress is not hindered in other areas e.g. the floors
above.
 Strength
Steel decking provides flexible reinforcement, combined with the comprehensive strength
of the concrete, for an all-round stronger slab.
 Easy on site handling
Steel decking is transported to site in pre-cut lengths, and in pre-packaged bundles.

13. 13
Disadvantages of composite slab
 Brittle
Composite is more brittle than wrought metal thus it is easily damaged.
 Crack
The biggest problem for composite slab is cracking.
 Temperature sensitive
Can cause expands and contracts with temperature change
 Might cause overloading
During placement on concrete, care should be taken to avoid overloading the decking or
supporting structural member.
 Replacement
Damaged or faded material must be replaced, and it is a soft material that wears easily.

14. 14
CASE STUDY
Embassy Suites ,Columbus, OH
Background
Building: Embassy Suites
Location: Columbus Ohio
Size: 135000 square foot
Capacity: 224 guest rooms, 7 storey
Completion: 2009
Designteam
Project architect: Bird Houk Collaboration
Project Engineer: Jezerinca Geers
General contractor: Brackett Builder

15. 15
CFS Use at Embassy Suites
Cold form steel(CFS) framing was used for interior and exterior load-bearing and non load-
bearing walls, and floor and roof joists. A very small amount of structural steel was used within
the top six floors of the cold-form steel portion of the structure. The podium level was
constructed of a 3 1/2” concrete over 3” deep composite metal deck on top of structural steel. In
order to provide the fire-resistance necessary in a residential building of this type, the floors and
flat roof are constructed with the Trade-Ready joist system supporting metal deck. The Trade-
Ready system is a proprietary system that allows for ease of utility installation through pre-
fabricated holes in the joists.
Cost Vs Competition
The general contractor initially estimated the cost of hotel buildings of this type to evaluate the
differences between steel and concrete. They determined that steel beats the competition by a
wide margin. The contractor estimates that the cost savings of CFS compared to concrete is at
least $10/SF of floor area. For the Embassy Suites, this would equate to approximately
$1,350,000 for the 135,000 square foot of floor area framed with CFS.
Construction Cycle Time
For hotel owners, timing is extremely important. The time from groundbreaking to finish was 13
months. The CFS framing was complete in 96 days. According to Hoying, “ the panelised
Worthington Integrated Building Systemschedule is very dependable and predictable. Panelized
steel systems obviously do not experience weather delays during cold weather was you would
see with concrete, block, and precast planks.” Because there is no concrete shoring to get in the
way, mechanical and electrical trades can get started quicker with their rough-in work.

16. 16

17. 17
Case Study II
Background
Building: Poly Canyon Village Student Housing
Location: San Luis Obispo, California
Size: 1,400,000 square foot
Year completed: 2009
Contract value: $250,000,000
Certification: LEED Gold
Designteam
Client: California Polytechnic State University
Architect: Niles Bolton Associates
CFS Use At Poly Canyon Village
CFS for this project was used for the wall framing exclusively relying on four-inch studs ranging
from 33 to 78 mil thickness. The thicker 68 mil studs were used at the ground floor and the stud
thickness decreased as additional floors were added. Floor framing was accomplished with
Dietrich TradeReady CFS floor joins with 9/16-inch shallow metal decking, and USG Levelrock
was poured one inch over the top of the decking for the subfloor. Roof framing consisted of steel
trusses fabricated by Pacific Coast Truss Fabricator, a CEMCO Company. Fire-treated structural
plywood was used on the roof.

18. 18
Tegan Sullivan of Clark Design/Build, who has served as the captain for the team, confirmed the
LEED certification requirement is one of the main reasons steel framing was selected. Cold-
formed steel and the panaelization process was attractive because of the off-site plant. In addition
to qualifying for LEED credit because of steel’s recycled content, the project also earned LEED
points because the manufacturing plant was located within 500 miles of the job site. The project
achieved a LEED Gold Certification from the U.S. Green Building Council.
Construction Cycle Time ( Schedule )
The construction was completed in six months less time using CFS framing compared to the
schedule for a concrete structural frame. The entire project could have been turned over a year
early but the lead time for some of the logistics like furnishings, retail build-out and training of
facility managers was not enough to advertise and lease the rooms.
The flexibility to pre-fabricate panels off-site definitely contributed to the project’s success, and
the speed at which the steel framing installer, KHS&S of California, was able to install the
structures on site allowed for all the subcontractors to be productive. The efficiencies gained
through pre-fabrication made it possible to start several components in several places at the same
time, which significantly cut down on any potential downtime for workers and subcontractors.”
The use of new techniques using steel helps reduce costs of the overall project and makes project
like Poly Canyon Village more marketable since steel is a stable, engineered material with
consistent properties. On completion inmate 2009, Poly Canyon Village is an impressive
apartment development for Cal Poly students with amenities including a swimming pool,
community center and a central retail plaza.

19. 19
Reference:
Emma Goodgion(2016). How Cold-Formed Steel is Made. Retrieved from 1 December 2017
from https://sfia.memberclicks.net/how-cold-formed-steel-is-made
Composite construction. Retrieved from 1 December 1, 2017 from
https://www.steelconstruction.info/Composite_construction
Composite construction. Retrieved from 1 December 2017 from
http://www.enme.umd.edu/~ccfu/ref/CompConstCamber1_Fu.pdf
Advantages of Composite Slabs. Retrieved from 1 December 2017 from
https://www.incoperfil.com/advantages-cms-1-51-189/
Metal deck(2017).The Advantages of Steel Decking. Retrieved from 1 December 2017 from
https://www.raisedfloor.co.uk/the-advantages-of-steel-decking/
Bill Hutchison(2007).Advantages-and-6-disadvantages-of-composite-decking. Retrieved from 1
December 2017 from http://www.renovateaustralia.com/2007/03/03/6-advantages-and-6-
disadvantages-of-composite-decking/
Emma Goodgion(2016). Advantages of Cold-Formed Steel Framing. Retrieved from 1
December 2017 from http://www.cfsteel.org/advantages-of-cold-formed-steel-framing
Prof. S.R.Satish Kumar and Prof. A.R.Santha Kumar(2015). Design of Steel Structures.
Retrieved from 1 December 2017 from
http://nptel.ac.in/courses/105106113/5_cold_form_steel/2_advantages.pdf
Steel framing alliance(2016). The Embassy suites is a seven story hotel built by Brackett Builder
of Troy, Ohio. Retrieved from 1 December 2017 from
http://www.steelframing.org/PDF/cycletime/EmbassySuites.PDF
Steel framing alliance(2016). Park 4200 is a six story apartment project built over a three story
parking garage. Retrieved from 1 December 2017 from
http://www.steelframing.org/PDF/cycletime/PolyCanyonVillage-FINAL-1.pdf