new building materials
TRANSCRIPT
USE OF NEW MATERIALS AND TECHNOLOGIES BY CPWD AT
MUMBAI
DR K M SONICHIEF ENGINEER, CPWD, MUMBAI
Post Tensioned Slabs• POST TENSIONED SLABS– CBI OFFICE BUILDING– NISM BUILDINGS (PARTLY)– INCOME TAX BUILDING UNDER CONSTRUCTION– IDBI BUILDING UNDER CONSTRUCTION
Advantages of PT Slab• Material Savings• Reduction in concrete is due to thinner concrete
members.• Reduction in rebar in floor elements.• Reduction in dead load resulting into saving in
concrete and reinforcement of structural members including foundation.
• Saving in building cladding, vertical mechanical/service elements, rebar and concrete in shear walls and other materials due to lesser sizes.
Steps in construction • Design
– The existing design has been based on Presscrete Post-Tensioning System (PPS). Concrete in one member panel shall be placed in one operation continuously without interruption.
• Concreting– Care is taken that the pre-stressing tendons do not get displaced or damaged prior to casting and during
casting. It is ensured that discharge of concrete is not directed onto the pre-stressing tendons. Vibrating is avoided from coming into contact with the pre-stressing tendons whenever possible. Proper compaction of the concrete in anchorage areas is ensured due to high local stresses in these areas and care taken that all the grout hoses remain exposed and protruding from the concrete surface.
• Stressing– After concreting, the carpenter removes the vertical sides end form work. All the stressing recesses are
cleared and pre-stressing barrels and wedges fixed to all pre-stressing castings. When concrete has reached the transfer strength as per the shop drawings (from the results of cube tests), stressing of cables is carried out. All cables are tensioned to the required jacking force and monitored through the pressure gauges.
• Grouting– Excess cable length is cut after the stressing. All pre-stressing tendons are ensured to be flushed with clean
water. Grout is mixed according to the design mix for at least two minutes until a colloidal consistency is produced. The water is put into the container first and the cement is then slowly added. When the cement and water are thoroughly mixed, the non-shrink additive added to the mix. The grout then is injected into the pre-stressing tendons. Grouting is carried out by injection at one end of the duct until clear grout flows out from the other end. The grout hose at the both end is then sealed. Grouting works commence when all scaffolds at a particular storey where grouting works are to be carried out, are removed.
Limitations• Since the cables or tendons in the slab have
been stretched to high tensile strengths, it is extremely important that the slab is not drilled, cut, chiselled or disturb in a way so as to expose the tendons
AAC BLOCKS• LOW DENSITY• GREEN MATERIAL
Service trenches• Not a very new concept• Being adopted in NISM
GFRC PANELS IN FACADE• Can be manufactured in many shapes• Can be painted
STAMPED FINISH CONCRETE
• Can be achieved in desired colours• The process includes – preparation of sub-grade, – placing of forms, – providing reinforcement for stability, – placing the concrete, – screeding and finishing the concrete, – applying colour and – stamping the concrete using desired moulds.
Stamped finish concrete
Innovative Floorings• Wood plastic composite flooring, • Maple hardwood sports flooring for special
applications, • Geofoam block flooring • Crazy patterned flooring of leather finish,
flamed and polished granite • Italian marble flooring
GEOFOAM FLOORING IN STEPS
Seating arrangement of class rooms
Innovative False Ceiling• Acoustic false ceiling • Cloud acoustic false ceiling
ACCOUSTIC FALSE CEILING
• Anutone False ceiling
Double Stack Car Parking
Glass• Structural Glazing• Partitions• Fire resistant Lobbies• Doors• Murals• Solar PV Panels
Dry Stone Cladding
STP
SOLAR ROOF TOP PANELS
AHU ON TOILET SLAB
SYNTHETIC GRASS
FOLDABLE PARTITION
LOUVERS
Energy efficiency• In new buildings only LED fitting or energy
efficient T5 fittings are provided.• Energy efficient Chillers are provided • Solar roof top PV Panels• Recycling waste water• Rain water harvesting
Pumping system• CPWD has adopted hydro-pneumatic
pumping system for water supply in most of large projects.
Green buildings• CPWD is constructing all green buildings and
getting them rated in Mumbai• CBI – 4 star GRIHA• IDBI Belapur – 3 star GRIHA• NISM – 4 star GRIHA• NTH – 3 star GRIHA• Income Tax Building – 4 star GRIHA
CBI OFFICEBUILDING
NATIONAL INSTITUTE OF SECURITIES MARKETS
Student and MDP Hostel blocks
Residential Block
NISM : Images
Orientation Block
Academic Block
Amphitheater
Hostel & MDP Block
Landscape development
Orientation Block
THANK YOU