This document provides information about a building technology course on alternative construction systems. It includes the course name, description, units, contact hours, prerequisites, objectives, and outline. The course aims to teach students about non-conventional construction methods, provide working details of different systems, understand advantages, and learn about latest technologies. The outline covers topics like cast-in-place and precast concrete, prestressed concrete, composite construction, tensile structures, and pre-engineered buildings. Studio equipment includes sample drawings.

1. BTAB115
ARCH. JAY LAWRENCE P. MARTINEZ, UAP, PIA

2. Course Name:
BUILDING TECHNOLOGY 5
ALTERNATIVE BUILDING CONSTRUCTION SYSTEMS
Course Description
Construction methods and techniques
for different types of buildings
using any appropriate alternative building construction system.
Number of Units for
Lecture and Studio
Lecture – 2 units
Studio – 1 unit
Number of Contact
Hours per week
Lecture – 2 hrs
Studio – 3 hrs
Prerequisite/
Co-requisite
Building Technology -3
Course Objectives
At the end of the course, the student should be able:
1. to gain knowledge on the fundamental principles governing the
design, purpose and application of the different types of non-
conventional systems of construction.
2. to acquire ability to provide working details of the various types
of alternative building construction systems and systems
components.
3. to understand better the advantages of using such system.
4. to acquire working knowledge of the latest system of
construction available in the building industry.

3. Course Outline
Alternative Building Construction Systems
1. Cast-in- place and Pre-cast
1. Floor System and Roof Slab System
1. Flat Slab
2. Flat Plate
3. Ribbed Floor Slab
4. Waffle Slab
5. Lift Slab
6. Spanstress Floor System
7. Slipform Method
2. Wall Panel Systems
1. Flat type
2. Ribbed type
3. Window type and wall type
4. Tilt-up Wall Panel System
2. Prestressed Concrete
1. Pre-tensioning
2. Post-tensioning
3. Composite Construction Method
4. Cable/ Tensile Structures
5. Membrane Structures
6. Shell Structures
7. Pre-Engineered Buildings
8. Geodesic Structure
Studio Equipment Sample working drawing and detailed drawing documents

5. General Term
 Composite construction is a generic term to describe any building
construction involving multiple dissimilar materials.

6. Structural Engineer
 Composite construction exists when two different materials are
bound together so strongly that they act together as a single unit
from a structural point of view. When this occurs, it is called
composite action.
House Building
 A flitch beam is a simple form of composite construction
sometimes used in North American light frame construction. This
occurs when a steel plate is sandwiched between two wood joists
and bolted together. A flitch beam can typically support heavier
loads over a longer span than an all-wood beam of the same cross
section.

7.  Composite construction refers to two load-carrying structural members that are
integrally connected and deflect as a single unit
 An example of this is composite metal deck with concrete fill, steel filler beams,
and girders made composite by using headed stud connectors
 A steel beam which is made composite by using shear connectors, composite metal
decking and concrete is much stronger and stiffer.
 Composite floor systems are considered by many to be the highest quality type of
construction
 This has become a standard type of construction.

8. It dominates the non-residential multi-
storey building sector.
This has been the case for over twenty
years.
It can be achieved, with minimum use of
materials.

9.  Composite construction is often so good can be expressed in one simple way.
 By joining the two materials together structurally these strengths can be
exploited.
 The reduced self-weight of composite elements has a knock-on
 Composite systems also offer benefits in terms of speed of construction.
 The floor depth reductions that can be achieved using composite construction can
also provide significant benefits in terms of the costs of services and the building
envelope.

10.  Composite columns may take a range of forms.
 As with all composite elements they are attractive because they play to the
relative strengths of both steel and concrete.
 This can result in a high resistance for a relatively small cross sectional area,
thereby maximizing useable floor space.
 They also exhibit particularly good performance in fire conditions.

12. Three general types of composite beam are
considered below. The drivers that are
relevant to a particular project will affect
which flooring system is the most
appropriate.
Downstand Beam
Long Span Solutions
Shallow Floor Solution

13.  The most common type of composite beam is one where a composite slab sits on
top of a down-stand beam, connected by the use of a through deck welded shear
studs.
 This form of construction offers a number of advantages
 the decking acts as external reinforcement at the composite stage, and during the
construction stage as formwork and a working platform.
 It may also provide lateral restraint to the beams during construction.

15.  A number of variations on the idea of down-stand beams are available to
meet long-span needs.
 They provide the opportunity to achieve longer spans (20 m or more) than are
possible using a 'standard' solid web, rolled down-stand beam.

16.  Shallow floors offer a range of benefits, which must be considered in the context of
a given project to identify when they are most appropriate.
 The shallowness of the floors is achieved by placing the slabs and beams within
the same zone.
 An added benefit is that a flat soffit is achieved.
 Encasing the steel sections within the slab also has benefits.
 A number of shallow floor solutions are available.
 The beams may either be rolled or fabricated, and a number of alternatives are
available.

18.  Composite slabs comprise reinforced concrete cast on top of profiled steel decking.
 The decking may be either re-entrant or trapezoidal.
 Trapezoidal decking may be over 200 mm deep.
 Additional reinforcing bars may be placed in the decking troughs.
 They are sometimes required in shallow decking when heavy loads are combined with
high periods of fire resistance.

19. COMPOSITE SLABS
•Re-entrant Decking •Trapezoidal
Decking

20.  Composite decking works together with the concrete fill to make a stiff, light-
weight, economical floor system
 Compare the composite decking ( above left), non-composite decking (above center), and
the form decking (above right)
 Composite decking is available in various profiles and thicknesses

22.  Decking with deformed ribs (or embossed decking), as shown, is commonly used
 The deformations on the ribs allow for a stronger bond between the concrete and
the decking
 Less common styles of composite decking include:
 Decking with the ribs formed in a dovetail or fluted pattern
 Decking welded wire welded to the ribs with fabric
 Decking with steel rods welded across the ribs

23.  Metal decking is placed on the structural steel at predetermined points in the
erection sequence
 Metal decking may be installed by the steel erection contractor or a separate
decking contractor
 As an alternative to welding, powder actuated tools may be used to attach metal
decking to structural steel
 Powder actuated tools use the expanding gases from a powder load, or booster, to
drive a fastener
 A nail-like fastener is driven through the metal deck into the steel beam
 The powder actuated tool, powder load, and fastener must be matched to the
thickness of the structural steel beam flanges

24.  Although design guidance exists for composite connections, they have been very
little used in the UK (or indeed elsewhere in Europe).
 In theory they appear to be attractive, as slab reinforcement can be used to avoid
the need to add to the steelwork connection.
 However, it is difficult to achieve the correct detailing for composite connections,
because the needs for strength, stiffness and ductility can border on the mutually
exclusive.

25.  Depending on the welding process used, the tip of the shear connector may be
placed in a ceramic ferrule (arc shield) during welding to retain the weld.
 Shear connectors create a strong bond between the steel beam and the concrete
floor slab which is poured on top of the metal decking
 This bond allows the concrete slab to work with the steel beams to reduce live load
deflection

26. INSTALLATION OF SHEAR
CONNECTORS
 The electrical arc process is commonly used for stud welding
 An arc is drawn between the stud and the base metal
 The stud is plunged into the molten steel which is contained by the ceramic ferrule
 The metal solidifies and the weld is complete
 The ferrules are removed before the concrete is poured

27.  Concrete is installed by a concrete contractor on top of the composite metal
decking, shear connectors, and welded wire fabric or rebar grid (crack control
reinforcing)
 Pumping is a typical installation method for concrete being placed on metal
decking
 10,000 to 15,000 sq. ft. of concrete slab may be installed per day depending on slab
thickness and crew size

28.  The shear connectors used in composite construction require specific inspections
and quality control
 Testing procedures are specified in the contract documents or by a local building
authority
 AWS D1.1 – Structural Welding Code – Steel, Section 7: Stud Welding (AWS 2004)
specifies the tests and inspections for shear studs

29.  It is an essential element of composite
construction if it is to perform adequately.
The main purpose of the shear connector is
to provide longitudinal shear resistance
between the materials so that they act
compositely and to facilitate the
interaction between the different
materials and to allow them to act as one.
(MCRMA,2003)

30.  The shear connections between steel beams and concrete slab is
typically achieved by headed steel studs, welded to the top flange of
steel beam and subsequently encased in concrete. The performance of
the studs depends on their dimensions and the spacing along the
flange of the beam. Near supports, where the shear forces are
greatest, the spacing is reduced. Shear suds can be welded through
steel decking.

31.  HEADED STUDS
 OSCILLATING PERFOBONDSTRIP
 T-RIB CONNECTORS
 WAVEFORM STRIPS
 T-CONNECTORS
 CHANNEL CONNECTOR

32.  The most common for of connecting
materials compositely is with the use of
headed shear studs. The behaviour of
headed studs does not vary significantly
when concrete properties are changed.
Resistance to shear depend on the
number of studs use and performance is
less that achieved by more modern
shear connectors such as perfobondstrip
or a welded T-section (Zingoni,2001)

33.  The advantages of stud connectors is that
the welding process is quick and simple, the
placement of the studs does not interfere
with the placement of reinforcement with in
the slab and they provide uniform
resistance with in the slab and they provide
uniform resistance to the shear in all
directions normal to the axis of the
stud.(Johnson,2004)

34.  The curved from of oscillating
perfobondstrip provides better force
transfer between steel and concrete than
a continuous strip. The load capacity of
this connector is larger than a headed
stud or welded T-section. This form of
connector is most suited to light weight
concrete or high strength normal weight
concrete. Problems with this form of
connections are difficulties in welding
the section to steel beam. (ZINGONI,
2001)

35.  Welded T-section connectors perform very well in comparison to headed studs and
achieve the same load resistance as oscillating perfobondstrip. Load capacity
increases when light weight concrete or high strength concrete is used.

36.  The objective of the curved form is
to improve the transfer of force
between the steel and surrounding
concrete as opposed to a straight
connector.

37.  This connector is a section of a standard
T-sections welded to the “H” or “I” section
with two fillet welds. T-connectors
evolved from the observation by
Oguejiofor (1997) that a large part of the
bearing capacity of a perfobond strip was
the result of the direct bearing of the
concrete at the front end of the
(discontinuous) perfobond strip.

38.  Cannel connector might not need
inspection procedures, such as bending
test of headed studs, due to strength of
most specimens is lower that their
monotonic strength by about 10%-20%.

40.  In a composite floor system the concrete acts together with the steel to create a
stiffer, lighter, less expensive structure
 Connecting the concrete to the steel beams can have several advantages:
 It is typical to have a reduced structural steel frame cost
 Weight of the structural steel frame may be decreased which may reduce foundation
costs
 Shallower beams may be used which might reduce building height
 Increased span lengths are possible
 Reduced live load deflections
 Stiffer floors

41.  The additional subcontractor needed for shear connector installation will increase
field costs
 Installation of shear connectors is another operation to be included in the schedule
 A concrete flatwork contractor who has experience with elevated composite slabs
should be secured for the job

42. VIDEO CREDITS: https://www.youtube.com/watch?v=j5NBk2BwG0c&t=76s

43. LEARNING TASK 4
REQUIRED DRAWINGS: (1:30m)
SECTION DETAILS
(enlarged 1:30m)
Beam Dimension of
250mm X 300 mm
Long size bond paper with standard margin and title block
TYPICAL BEAM CROSS SECTION
COMPOSITE CONSTRUCTION METHOD
Slab Thickness of 10 mm
ISOMETRIC DETAILS
(enlarged 1:30m)
I-BEAM
CONCRETE SLAB SHEAR CONNECTORS

44. Let me know if you
have questions or
clarifications.