Post on 21-Mar-2017
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REINFORCED BRICKWORKREINFORCED BRICK WORK IS THE ONE IN WHICH THE BRICK MASONRY IS STRENGHTENED BY THE PROVISION OF MILD STEEL BARS, HOOP IRON, EXPANDED MESS.
(RBW)
Group Members :BINDRESH KR.SATYA PRAKASHRAHUL KR.
INTRODUCTION
Reinforced brick masonry (RBM) consists of brick masonry which incorporates steel reinforcement embedded in mortar.
This masonry has greatly increased resistance to forces that produce tensile and shear stresses.
The reinforcement provides additional tensile strength, allowing better use of brick masonry's inherent compressive strength.
The two materials complement each other, resulting in an excellent structural material.
HISTORY
Brick masonry is one of the oldest forms of building construction, and reinforcement has
been used to strengthen masonry since 1813.
SIR MARC ISAMBARD BRUNEL
BORN 25 April , 1769
DIED 12 Dec. 1849
NATIONALITY French
KNOWN FOR Thames Tunnel
REINFORCED BRICK WORK USES
• FIRST CLASS BRICK
CEMENT MORTAR
• REINFORCEMENT
FIRST CLASS BRICK well burnt table moulded brick uniform in colour uniform length and wide sharp well defined edges Smooth surface without having any : Flaws Cracks Stone grits
FIRST CLASS BRICKPROCESS OF MANUFACTURE
Preparation of earth Moulding
drying
Burning
CEMENT MORTAR This term is used to
indicate a paste prepared by adding required quantity of water to a mixture of
matrix like cement adulterant like sand.
The combined effect of the two components of mortar is that the mass is able to bind the bricks or stones firmly.
BINDING MATERIAL
AGGREGATE
CEMENT MORTAR cement mortar uses in R.B.W. has HIGH DENSITY.
it holds reinforced at desired position
cemen:sand ratio :
1 : 3 (MOST COMMON) 1 : 4
BINDING MATERIAL OPC (Ordinary Portland Cement) PPC (Portland Pozzuolana Cement) SRC (Sulphate Resisting Portland
Cement) Low Heat Portland
Cement Rapid Hardening Portland
Cement
REINFORCEMENTPRINCIPLES OF REINFORCEMENTS
tension occurs when bending forces act on structural elements such as
beam
cantilevers
steel is excellent in resisting tension and can be incorporated into brickwork as reinforcement
the steel must be located in the masonry where tension is occur- typically at the bottom of a horizontal beam and at the top of a horizontal cantilever.
WROUGHT IRON FLAT BARS
• Two strips of hoop iron are used per header brick
•One hoop iron per stretcher brick
• steel flats may also be used in place of hoop iron
•Its usual to reinforce every sixth course
STEEL MESS steel messes also known as EXMET made from rolled steel plates Its expanded by machine and is known
as expanded EXMET Provided at every third course Available in widths of 65mm, 176mm and 230 to 305mm with thickness of
0.6mm,0.8mm and 1mm. Supplied in coils of 83m length
BRICK ARCHES
SEGMENTAL ARCH : In college canteen
SEMI CIRCULAR ARCH
BRICK SLAB
REIFORCED BRICK BEAM
VERTICAL REINFORCEMENTS
Mild steel bars is provided in brick columns, brick walls and brick retaining walls
sometimes, in such circumstances special bricks, with one or two holes extending upto the face
Brick retaining walls are often reinforced since such a work is cheaper than R.C.C.
EXAMPLE OF VERTICAL
REINFORCEMENT
PIERS
ISOLATED PIERS
ATTACHED PIER
PIERS
COLUMNS
NOMINAL COVER TO REINFORCEMENTS
Exposure Minimum nominal SIZE (mm)
Mild 20
Moderate 30
Severe 45
Very Severe 50
Extreme 75
WATER Clean water to be used in
the preparation of mortar.
The pH of water not less than 6.
Sea water not to be used in R.B.W.
Limits in Mixing Water Sulphates(as SO3)---
400mg/litre Chlorides (as Cl )---500mg/litre
CURING OF R.B.W. the act of maintaining controlled conditions for freshly
brick work for some definite period following the placing and finishing operations to assure the proper hydration of cement and proper hardening of brick work.
Methods of Curing: Retaining formwork Shading of brick work Covering of surfaces with cotton mats Continuous sprinklings of exposed surfaces Ponding method Membrane curing Steam curing Electrical method of curing
Retaining Formwork: useful for curing vertical
surfaces of structural elements
Useful in cold countries Not sufficient for hot
countries because formwork can only preserve the moisture inside the brick work, but cannot prevent evaporation.
SHADING OF R.B.W. Essential in dry weather
objective of shading to prevent the evaporation of water
Also protects the surface from rain
Limited application
Covering Surfaces with wet material:
• most widely used
Continuous sprinklings of exposed surfaces
Ponding method: most efficient method of curing. suitable for construction of arches, roof slabs, lintel etc.
Membrane curing: membrane serves as a physical barrier to prevent loss of moisture from the brick work to be cured
Steam curing: It leads to increase rate of strength development
Electrical method of curing: by passing alternate current of low voltage
ADVANTAGE OF R.B.W. OVER R.C.C. Additional strength imparted to the masonry
Low cost housing
low labor cost
Reinforced brick beams and lintels allow the designer to achieve exposed brick on the underside of these element.
It plays an important role in earthquake more better than R.C.C.
Brick retaining walls are often reinforced since such a work is cheaper than R.C.C
REASONS FOR DETORIATION • Lower unit cement content.
• Presence of high chloride content
• Inadequate cement mortar cover to reinforcements
• Ingress of moisture
• Carbonation of mortar in the neighbourhood of steel
PREVENTION Basic principle of prevention of
corrosion is to maintain passivity of the embedded steel reinforcement by the high alkalinity.
By dipping the bars in hot tar
In case of mess : the metal in the coil form is coated
with oil and deep in asphaltum paint.
EXAMPLES
OFREINFORCED BRICK WORK
name : Laurence Wilfred BakerBorn : 2nd March 1917Died : 1st April 2007Education: Birmingham Institute
of Art and DesignResided in : Trivandrum, Kerala.
The Gandhi of architecture
KNOWN AS BRICK MASTER
LAURENCE WILFRED BAKER’S HOME
HOUSING IN U.S. Single storey building plan
Less affordable housing plan
9-10 storey housing plan
Thank you