National Symposium on ‘Affordable Housing’, New Delhi 22 July 2013
Affordable Rapid Mass Housing
Department of Civil Engineering IIT Madras, Chennai
As of 2012:
Urban Housing Shortage : 18.78 Mi Units
Rural Housing Shortage : 40 Mi Units 80 m2 MIG+ : 0.82 Mi Units
LIG: 7.41 Mi Units 50 m2
EWS: 10.55 Mi Units
25 m2 Carpet area
“Affordable”? Annual Income: EWS: Rs 90,000 LIG: Rs 120,000 MIG: Rs 300,000
Distribution of 2012 Housing shortage among Economic categories (in Millions) 2
OPPORTUNITIES …
Earlier Mass Housing was mostly a Government activity
Archaic laws restricted availability of Urban Land for Large Housing Projects
Emphasis on labor orientated Technologies led to lower productivity
There were No Incentives for Standardization of Designs & Use of Prefabricated Building Elements
High Cost of Capital
Need for Applied Research for Infrastructure Development of India
Affordable housing: design & construction method optimization
Technology relevant to India
Experience of other countries not directly usable due to high costs
Social relevance and acceptability
Comprehensive solution to make private & public sectors deliver with reasonable profit
Issues of Concern Affordability: target clientele Scalability: mass housing, prefabrication, modular construction Sustainability: embodied energy, CO2 emission, recycling
Local availability / scarcity of materials (river sand) Rapidity in construction Structural stability and strength (earthquake resistance)
Functionality: space utility, lighting, ventilation Aesthetics Constructability: quality, planning, skill and safety issues Durability: maintenance issues, life of structure Government policies, subsidies
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Recent methods in Housing construction Precast construction Tunnel form construction Large area formwork construction Lightweight concrete construction Cold-Formed Steel (CFS) housing system GFRG building system
GFRG wall panel (Rapidwall®) – an alternative building material, introduced in 1990 3m
Largest light weight wall panel 44 kg/m2
Gypsum plaster, reinforced with chopped glass fibres, 300 – 350 mm long (0.8 kg/m2) 9
Advantages of GFRG Building Systems
reduction in structural weight of building saving of cement, steel, sand, water more carpet area saving of construction time reduction in emission of CO2 effective use of industrial waste product suited for affordable mass housing
Applications
As lightweight load bearing walls
As partition infill walls in framed buildings
As shear walls*
As floor slabs / roof slabs: with reinforced concrete micro beams*. * Design and construction methodology developed at IIT Madras
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Outcome of R&D work at Structural Engg Lab, IIT Madras, since 2004:
To enable IIT Madras to complete R&D efforts and promote technology transfer, Dept of Science & Technology, Govt of India has recently awarded a project with funding of 11 Rs 13.2 million; additional support from industry.
Axial Loading with Out-of-plane Bending Recommendation for minimum eccentricity causing out of plane bending: 0.05×wall thickness t (6.2 mm for t = 124 mm) P
2850 mm
e
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Design options : positioning of rebars
Presence of rebars in the concrete does not add to the axial strength 13
Hysteretic Behaviour
1.02 m Wide panel Subjected to only reverse cyclic load 14
2.02 m wide panels having door opening and subjected to constant axial load & in-plane lateral reversed cyclic loading.
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GFRG Building System ------ G+7 at Mumbai
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With 2-3 GFRG panels a small house can be built which is strong and durable, with living comfort.
By cutting into required sizes, 4 for four walls, 2 pieces as roofing panels for sloped roof, a small house can be built within days … 17 17
Mass Housing Using GFRG Panels – single storey
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GFRG demo building at IIT Madras (1981 sq ft)
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GFRG demo building at IIT Madras (1981 sq ft) kindly check youtube link: http://www.youtube.com/watch?v=UUQEUcB7cMM
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GFRG Demo Building at IIT Madras
Typical floor plan
Built area =1981.3 sq.ft.
PRECAST HOUSING
Ground + 4-floor structure 45 flats each of built-up area 28 square metre Total precast concept
Precast components used
Footings Columns
Floor / Roof beams
Floor / Roof planks
Wall panels
Stair flights
Cup boards
Kitchen platforms
Water tanks
Precast Technology in Housing
Precast Integral Wall System
Project: Slum rehabilitation housing at Bhoiwada, Mumbai for M/s Omkar Realtors.
Ground Floor: Cast-in-Place construction (H=4.15m) Typical Floors (1-23): Precast Bearing Wall system (H=2.85m)
Tallest Precast Building in India 70 m tall with plan 45.8m × 19.69m
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(Photo Courtesy: L&T, Mumbai)
Tallest Precast Building in India
Side Elevation
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Front Elevation
Ground Floor Plan (Cast-in-Situ)
Ground Floor Plan ( 250 and 200 mm thick Walls ; Built-up Area 745 m2) 26
Typical Floor Plan (Precast)
Typical Floor Plan (160 mm thick Walls and 150 mm27thick slabs; Built-up Area 875 m2)
Typical Floor Elements (Precast)
Types of Precast Elements used for construction 28
(Courtesy: L&T )
Typical Floor Elements (Precast)
Assembling of one unit with common area (Courtesy: L&T ) 29
Precast Construction Sequence
Sequence of Execution of Precast Portion (Courtesy: L&T ) 30
Precast Construction
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(Photo Courtesy: L&T, Mumbai )
MECHANIZED FORMWORK SYSTEM … TUNNEL FORM • RCC floor slab & walls cast in one pour • Quick stripping & form removal • One / two flats in one-day cycle
ALUMINIUM FORMWORK • Light weight • Simple connection arrangement • Easy to handle • More than 100 repetitions
• Eliminates use of P & M • Improves Labour productivity
TISCO Jamshedpur
L&T FLEX TABLE SYSTEM
TENEMENTS FOR SLUM REHABILITATION AT MUMBAI NO. OF HOUSES 5,900
CIDCO MASS HOUSING
KHARGAR, MUMBAI NO. OF HOUSES
1456
Aluminium Formwork -MIVAN
Cold Form Steel
G+3 CFS House at Raigarh, Chattisgarh, --- J B Infra Pvt Ltd
