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Cast Insitu
Precast
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FLOW OF PRESENTATIONFLOW OF PRESENTATION
1 NEED FOR INNOVATION IN CONSTRUCTION
2 COMPARISON OF CONVENTIONAL AND PRECAST TECHNOLOGY
3 PRECAST TECHNOLOGY
4 CASE STUDIES
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
6 SUSTAINABLE GOALS
7 RISK MANAGEMENT
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION--Shortage of skill & ExpertsShortage of skill & Experts
Construction industry employs approx 49 million personnel.
Sharp decline in skilled workers and engineers.
The table below shows statistics from Planning Commissions 11th five year
plan (2007-2012).
SR NO. DESCRIPTION NOS. IN 1995(IN 1000S) % WITH TOTALNOS. NOS. IN 2005(IN 1000S) % WITH TOTALNOS.
1 ENGINEERS 687 4.71 822 2.65
2 TECHNICIANS &
FOREMAN
359 2.46 573 1.85
3 CLERICAL 646 4.4 738 2.38
4 SKILLED WORKERS 2,241 15.34 3,267 10.57
5 UNSKILLED WORKERS 10,670 73.08 25,600 82.45
6 TOTAL 14,600 100 31,000 100
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51.0
52.0
53.0
54.0
55.0
56.0
57.0
58.0
59.0
60.0
61.0
0
100
200
300
400
500
600
2011 2012 2013 2014 2015
Supply
Demand
Gap(%)
Demand for affordable housing in top seven cities is likely to outstrip
supply by 2015, according to global consultant Cushman & Wakefield. Total demand of 3.94 million units of residential property in the next five
years at CAGR of 11%.
Source: Cushman & Wakefield Research
HOUSINGUN
ITS
(IN
THOUSAN
DS)
YEAR
GAP(
%)
1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION--Demand & SupplyDemand & Supply
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Estimated supply by the use of conventional methods is expected to be
approximately around 1 million units from top 7 cities. Demand for the top 7 cities is forecasted as 2.3 million units indicating a
shortfall of 1.3 million units.
Source: Cushman & Wakefield Research
HOUSING UNITS (IN THOUSANDS)
0 200 400 600 800
Mumbai
Pune
Hyderabad
Kolkata
NCR
ChennaiBangaluru
Supply
Demand
Gap
Demand Supply Projections 2011-2015
1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION--Demand & SupplyDemand & Supply
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Simple adaptation of western ideas for processes does not supporthousing solutions for low-income parts of society.
Use of designs that are appropriate to the economic, social, cultural
and natural conditions of each community are of vital importance.
Outflow of currency to purchase machinery and raw material for local
production should be stopped.
Standards and rules from developed world make housing unavailable
in third world and developing countries.
1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTIONPRINCIPLES IN AFFORDABLE HOUSINGPRINCIPLES IN AFFORDABLE HOUSING
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CONCLUSION: TechnologyCONCLUSION: Technology
"When compared to any other discipline of building construction,
civil construction is conventional in it's approach. We need to
breakaway from the convention to meet the demand and de riskcritical construction activities. One such technology proven
elsewhere in building construction is Precast
-Innovations in other discipline
High speed lifts Automation
Censors to control usage of electricity and water
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION--Cost AnalysisCost Analysis
37%
18%
45%
Concrete Yard set up/Erection
28%
63%
2%
5%
2%
Land
ConstructionDesign Fees
Marketing
Admin9%
51%
21%
7%
2%10%
Cost analysis for structure
Sub structure super structure
Architecture PHE
FPS Electrical
Cost analysis for Precast
Margin
25%
Project
Cost75%
Yard
40%
Erection
60%
Project Costs
Selling Rate
75%
4.5%
Rebar
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- PROJECT MANAGEMENTPROJECT MANAGEMENT
Phase 1 Phase 2 Phase 3 Phase 4
Initiation Planning Execution Close out
Time
Cost of Making Change Curve
High
Low
Project Life Cycle
Plan Act
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- PROJECT MANAGEMENTPROJECT MANAGEMENT
Phase 1 Phase 2 Phase 3 Phase 4
Initiation Planning Execution Close out
Time
High
Low
Project Life Cycle
Plan Act
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- PROJECT MANAGEMENTPROJECT MANAGEMENT
Phase 1 Phase 2 Phase 3 Phase 4
Initiation Planning Execution Close out
Time
Value Addition Curve
High
Low
Project Life Cycle
Plan Act
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- PROJECT MANAGEMENTPROJECT MANAGEMENT
Phase 1 Phase 2 Phase 3 Phase 4
Initiation Planning Execution Close out
Time
Amount of Stake Curve
High
Low
Project Life Cycle
Plan Act
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Precast Concrete construction
a) Full Precast system
All elements including faade are precast
b) Precast column / walls with flat plate / flat slab
c) Precast beam and precast slab
Floor system could be
Precast hollow core slab + cast-in-situ topping
(this can be used for long span structure of 8.0m to 15.0m
Spans) Precast plank with cast in situ topping
1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTIONPRECAST SYSTEMPRECAST SYSTEM -- OPTIONSOPTIONS
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- BENEFITS OF PRECAST SYSTEMBENEFITS OF PRECAST SYSTEM
Construction time can be reduced by 40%.
- Layout should be suitable for mechanization
Labour requirement can be reduced by 40%.
High Quality Finishes.
Design flexibility by maximizing repetition can reduce cost and
aids speed of construction.
Faster construction results in earlier cash flows and leads to
reduced capital costs.- Central yard can be a strategy for huge developments
Reduces Environmental impact.
Enhances Energy Performance.
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- BENEFITS OF PRECAST SYSTEMBENEFITS OF PRECAST SYSTEM
Durable and require little or no maintenance to preserve theiroriginal look.
Fireproofing material is not required as Precast concrete is non-
combustible.
Acoustical isolation and vibration attenuation.
Improved air quality
Various kinds of architectural finishes can be easily incorporated
in design.
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1.NEED FOR INNOVATION IN CONSTRUCTION1.NEED FOR INNOVATION IN CONSTRUCTION-- LIMITATIONS OF PRECAST SYSTEMLIMITATIONS OF PRECAST SYSTEM
The system has certain limitations. Precast member sizes will be restricted by crane capacity
Progress depends on hoisting facilities. If it breaks down
progress of work will be affected
Lack of planning will derail the schedule. Missing of anycomponents will affect the progress of work seriously.
Proper logistic planning and inventory checks are required
Requires skilled labour for erection.
BACK
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2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
Sr No. Description Conventional technology Precast technology
For construction of 1 Million sq.ft. G+20 (6 bldgs).
1 Construction time 34 Months 24 Months.
2
Cost
(considering labour and
construction costs)
100% 95%
3 Labour requirement 5 Lakh man days/year 2.5 Lakh man
days/year
4 Quality
Quality control at site is
difficult owing to variable
parameters.
Factory production
ensures quality
product.
5 Safety
Safety at site requires
more attention and
comparatively more
expensive
Less safety
measures needed
when compared
with conventional.
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2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
Accumulatedcosts/pa
yments
Design Period
Mobilization
Construction Time
Conventional
Construction
Precast
Construction
Construction Payment Schedule
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
ting of Precast Elem
Substructure
Superstructure
Finishing
Handing Over
Proposed Tentative Construction Schedule-Precast
ActivityMonth
Mobilization
Design
Precast Yard Set up
2M
3M
6 M
10M
6M
11M
11M
1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
Finishing
Handing Over
Proposed Tentative Construction Schedule-Conventional
ActivityMonth
DesignSubstructure
Superstructure
3M6M
25 M
20 M
1
2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
2.COMPARISON WITH CONVENTIONAL
CONSTRUCTION
BACK
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3.PRECAST TECHNOLOGY3.PRECAST TECHNOLOGY
Following are the two widely accepted systems suitable for Residential buildingconstruction:
1. Large Panel System.
2. Framed System.
PrecastTechnology
Large PanelSystem
Panel
System
ModularSystem
Combinationof Both
FramedSystem
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3.PRECAST3.PRECAST TECHNOLOGYTECHNOLOGY
--LARGE PANEL SYSTEMLARGE PANEL SYSTEM
Consists of large concrete walls and slab panels
Horizontal slabs acts as a diaphragm in transferring load.
Height of panels is one floor high.
Gravity load is resisted by vertical panels.
Panel connection are the key structural components.
Seismic shear forces are resisted by horizontal and
vertical joints.
Horizontal panels can be hollow or solid.
Vertical panels can be load bearing and non load bearing
Vertical panels can be solid or sandwich panels.
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3.PRECAST TECHNOLOGY3.PRECAST TECHNOLOGY
--FRAMEDFRAMED SYSTEMSYSTEM
CONCEPT:
All elements including facade are precast.
Precast column, precast beam and precast slab.
Nonstructural Infill walls were also cast along with Precast column and
beam.
Foundation Cast in situ, Few non typical elements can be cast insitu.
Floor system consists of Precast plank with cast in situ topping.
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Columns, beams and slabs are factory made precast elements.
SCHEMATIC DIAGRAM OF FRAMED SYSTEMS.SCHEMATIC DIAGRAM OF FRAMED SYSTEMS.
3.PRECAST TECHNOLOGY3.PRECAST TECHNOLOGY
--FRAMEDFRAMED SYSTEMSYSTEM
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3.PRECAST TECHNOLOGY3.PRECAST TECHNOLOGY
--FRAMEDFRAMED SYSTEMSYSTEM
3 PRECAST TECHNOLOGY3 PRECAST TECHNOLOGY
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3.PRECAST TECHNOLOGY3.PRECAST TECHNOLOGY
--FRAMEDFRAMED SYSTEMSYSTEM
BACK
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Full advantage of precast concrete construction is
achieved when the building has been designed for high
construction speed and maximum repetition.
In every precast concrete projects the following aspects
are important for the design team:
Architecture
MEP services
Structure
Manufacturing
Erection
5. DESIGN ASPECTS OF PRECAST CONCRETE
CONSTRUCTION
5. DESIGN ASPECTS OF PRECAST CONCRETE
CONSTRUCTION
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The architect should be considering the following
points:
Simple and symmetrical layout and elevations.
Achieve standardization and repetition.
Modular grids.
Modular design has big impact on costing.
Design with larger floor spans.
Minimize joints.
Keep precast elements as large as possible, but
maximum around 5 to 6 Tons.
ELEVATION
HOLLOW CORE SLAB FINISHES
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
ARCHITECTURAL ASPECTSARCHITECTURAL ASPECTS
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5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
ARCHITECTURAL ASPECTSARCHITECTURAL ASPECTS
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Integrate architecture services and structure .
Avoid last minute changes.
Modular Design modular principles can be
strictly followed.
A balance should be found between modular
design and customized prefabrication.
Flexibility Flexibility in precast concrete building
projects can be achieved by creating larger floor
spans with larger open spaces.
HOLLOW CORE SLAB FINISHES
HOLLOW CORE SLAB FINISHES
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
ARCHITECTURAL ASPECTS
Precast Architectural Designs
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In precast concrete building projects, it is important that the MEP service
consultants and the MEP vendors are part of the design team. Services like airconditioning, electrical and plumbing have to be an integrated part of the precast
design.
MEP SERVICES IN HOLLOW CORE SLABS
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
MEP SERVICES
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Wall panels can be provided with electricity conduits , electricity boxes and
openings for ducts. Hollow core slabs (HCS) can be provided with electricity boxesand block outs.
Precast planks with RCC toppings can be provided with electricity boxes and
conduits.
PLUMBING WORK IN HCS WITHOUT SUNK
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
MEP SERVICES
MEP SERVICE IN HOLLOW CORE SLABS.
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India being an earthquake prone country the seismic resistant requirements
are the most important criteria of the structural design.Looking at the requirements, the following design rules should be followed:
Simple and symmetrical layout.
Uniform distribution of mass and structural stiffness over the height.
Avoid torsion.
Ductile behaviour of the structure.
Transfer of vertical loads between wall panels can be achieved by direct
structural connection.
The precast floor units should be properly joined together to act as a floor
diaphragm that transfers the lateral load to the shear walls.
The shear walls will transfer the lateral loads to the foundation by acting as
cantilevered walls.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
STRUCTURAL ASPECTS
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Customization according to the requirements of the project
Capabilities of manufacturing unit to be considered in
design stage
Standardization of embedded parts, lifting anchor,
reinforcement etc.
Reduction of damage by chamfering the edges of the wall.
Tapering of block outs.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
MANUFACTURING ASPECTS
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5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
MANUFACTURING ASPECTS
Mould Design.
Suitable material including steel, timber/
plywood is selected on the basis of
No of repetitions.
Required surface finish.
Complexity of Precast Element.
Cost competitiveness is enhanced by
using adjustable moulds.
Adequate no of braces, ties and struts
should be provided for proper casting
of elements.
3 D Pod Mould
Adjustable Mould
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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Crane position and lifting capabilities.
Lifting speed and speed of erection.
Space for mobile cranes / Crawler cranes.
Easy access to connections.
Tolerances (Ref:IS 15916:2010, PCI 117,Appen I).
Erection Sequence.
Easy and fast erection.
Filling of joints with grout / mortar.
Position of Props and supporting structures.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
ERECTION ASPECTS
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
DESIGN ASPECTS
Design of Precast elements. Involves understanding the method
of fabrication.
Involves aspects that facilitate the
erection and assembly of elements
on site.
Integration of different elements,
such as beam-wall system, multi-
tier columns and three dimensional
units.
Parapet Beam
3 - D Pod elements
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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Structural integrity - Diaphragm action
lateral forces (seismic & wind)
Ref : Seismic design of floor
diaphragms - Farzad Naeim & R.Rao
Boppana
Designed against progressive
collapse/Robustness/ accidental
actions.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
CONNECTION DESIGN ASPECTS
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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The wall panels connections can be classified into horizontal joints and
vertical joints.
The horizontal joints have to transfer vertical loads as well as lateral
loads.
The vertical joint can either be structural joints which have to transfer
shear forces or non structural joints which dont have to transfer any
forces.
For fully monolithic behaviour the protruding reinforcement
connection in combination with drop in stirrups can be used.
The connection in Hollow core slabs should transfer the internal
diaphragm forces and it should be designed as structural integrity tie.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
CONNECTION DESIGN ASPECTS
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
CONNECTION DESIGN ASPECTS
Joints and Connections
Joints are designed on the basis of
Transfer of loads from a precast
concrete element to the supporting structure
to form the structure.
Avoiding congestion at joints.
Avoiding penetration of forms.
Allow for erection and production tolerances.
Easy assembly and accessibility.
Column-BeamJoint.
External wall joint.
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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Progressive collapse / Robustness
These effects may generally be prevented if the following precautions are
taken. (Ref : IS 15916:2010)
o Notional horizontal load
o Design of ties
Peripheral ties
Internal ties
Floor to wall ties
Vertical wall ties.
Ref : Precast concrete structures
by Kim.S.Elliot.
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
CONNECTION DESIGN CONCEPTS
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
LOCATION OF TIES IN PRECAST SKELETAL STRUCTURES
1 Internal floor ties
2 Peripheral floor ties
3 Gable peripheral floor ties4 Floor to wall ties
5 Internal Beam ties
6 Peripheral Beam ties
7 Gable Peripheral beam ties
8 Corner Column ties
9 Edge Column ties10 Vertical Column ties
11 Vertical wall ties Location of ties in Precast Skeletal Structures
5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5 DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
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Typical Cross section
Typical Plan view
Reinforcement
designed for chord
forces (tension)
5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION5. DESIGN ASPECTS OF PRECAST CONCRETE CONSTRUCTION
CONNECTION DETAILS : FLOOR TO FLOOR DIAPHRAGM
BACK
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Resource Efficient
Concrete- made from water, sand, aggregates and cement(limestone)
Abundantly available materials.
Waste by products from power plants and manufacturing facilities can
be used in concrete
Energy Efficient
Thermal mass of concrete saves energy by reducing temperature
swings in buildings.
Concrete has low energy requirements for production.
Concrete has low transportation energy costs as it is produced by
materials available locally.
Light colored precast concrete roof pavers reduces Heat Island
Effect.
6.6. Sustainable GoalsSustainable Goals
i bl li bl l
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Highly Durable
Concrete gets stronger with age.
Strength gained by concrete for years and even decades.
Ecologically Preferable
compared to wood, iron ore mining, extraction for constituents of
concrete is less disruptive to land
Concrete reduces construction waste and can be recycled.
Recyclable
Concrete- crushed and used as aggregate in new concrete mixtures for
infrastructure projects.
Steel reinforcement can be recycled again.
6.6. Sustainable GoalsSustainable Goals
66 S i bl G lS i bl G l
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6.6. Sustainable GoalsSustainable Goals
Reduction of CO2 emissions.
Industrial wastes such as slag cement and silica fume reduces the
amount of cement which in turn reduces CO2 emissions
Reduces the amount of materials used.
Precast concrete is designed to optimize the amount of concrete
used. For ex: hollow core slabs.
0
20
4060
80 Total self
weightGravel & Steel
Cement
Water
45% savings in hollow
core slabs
66 S i bl G lS i bl G l
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Reduces the toxicity of materials.
As a manufactured product under controlled conditions in the plant,
precast concrete generates less waste and waste generated has low toxicity.
Indoor Air Quality.
Concrete contains low to negligible VOCs.
Also, concrete has resistance to moisture.
No renders and plasters required for internal applications.
6.6. Sustainable GoalsSustainable Goals
BACK
7 RISK MANAGEMENT7 RISK MANAGEMENT
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Risk Management is the process of planning, leading and controlling
the resources and activities of the organization to
To fulfill its objectives cost effectively
To protect and grow corporate assets
To enhance shareholder value.
Risk Management Techniques in Construction:
Structural design principles
Codal standards against Progressive collapse
Case study Effective Progressive collapse design
7. RISK MANAGEMENT7. RISK MANAGEMENT
7 RISK MANAGEMENT7 RISK MANAGEMENT
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7. RISK MANAGEMENT7. RISK MANAGEMENT-RONAN POINT, LONDON
22 storey block of flats built in 1966-68 (one
of nine identical blocks).
Precast concrete walls and floors with in
situ joints between units. No in situ core or
shear walls.
Collapse of south east corner over full
height of building caused by a gas explosion
in corner flat on the18th floor in May 1968.
5 people died. Emergency strengthening
works carried out.
South east corner of building rebuilt and
occupation of building continued.
7 RISK MANAGEMENT7 RISK MANAGEMENT
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Precast floor units 7in thick and reinforced.
Wall panels 6in thick with little or no
reinforcement.
Diagram shows typical connection detail with
emergency strengthening angles.
5th Amendment to the Building Regulations
in 1970 (includes requirements for the
prevention of progressive collapse).
Evacuation of Ronan Point and 8 sister blocks
1984.
Detailed survey carried out 1984.
Building dismantled 1986.
7. RISK MANAGEMENT7. RISK MANAGEMENT-RONAN POINT, LONDON
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7 RISK MANAGEMENT7 RISK MANAGEMENT
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Detailing
The code adopted addresses progressive collapse,
ties and ductile detailing.
Protruding reinforcement from floor planks
overlap with the reinforcement in adjacent plank.
After erection overlapping bars are threaded with
11mm steel strands effectively interlocking them
and are grouted.
Wall panels were casted with protruding loops
which is threaded with steel bars and grouted
with adjacent wall panels.
Bars from one level to another were connected
with nuts inside connecting bracket.
7. RISK MANAGEMENT7. RISK MANAGEMENT- KHOBAR TOWERS, SAUDI ARABIA
7 RISK MANAGEMENT7 RISK MANAGEMENT
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Performance
The code addresses progressive collapse, ties and
ductile detailing.
Collapse was limited to the external facade wall.
Exterior shear wall was completely destroyed
but no progressive collapse.
Interior walls and slab panels had extensive
damaged but did not collapse
The precast elements had sufficient ductility
detailing to with stand the impulse force.
The interlocked ductile connections maintained
integrity of the structure preventing progressive
collapse.
7. RISK MANAGEMENT7. RISK MANAGEMENT- KHOBAR TOWERS, SAUDI ARABIA
BACK
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THANK YOU