The document discusses housing construction technology and materials. It provides an introduction and outlines guiding principles. It then describes various construction methods and materials that have been developed over the past 2-3 decades for foundations, walls, blocks, and reinforced concrete. These include techniques like under-reamed pile foundations, lean concrete mixes, cavity walls, modular bricks, load-bearing walls, stone block masonry, ferrocement, use of flyash, and fibre-reinforced concrete. The document also discusses seismic isolation technologies, passive energy dissipation devices, and retrofitting options to improve earthquake performance of housing.

1. HOUSING CONSTRUCTION
TECHNOLOGY
AR.VIJAY KUMAR

2. CONTENTS:
 INTRODUCTION
 GUIDING PRINCIPLES FOR HOUSING DESIGN &
CONSTRUCTION TECHNOLOGY.
 AVAILABLE CONSTRUCTION TECHNOLOGY & BUILDING
MATERIALS.
 TECHNICAL ISSUES & RECOMMENDATIONS
 SESMIC ISOLATION
 PASSIVE ENERGY DISSIPATION DEVICES.
 EARTHQUAKE PERFORMANCE
 RETROFIT
 RISK & CHALLENGES.

3. INTRODUCTION
 WHEN A DISASTER AFFECTS HOUSING, THERE ARE
IMPORTAINT CHOICES TO BE MADE IN THE REBUILDING
EFFORTS RELATED TO THE DESIGN & CONSTRUCTION
TECHNOLOGY.
 THESE CHOICES MUST BE TAKE INTO ACCOUNT :
ENVIORMENTAL, ECONOMIC, SOCIAL, INSTITUTIONAL &
TECHNICAL FACTORS.
 THE SIZE & SCALE OF THE PROJECT AS WELL AS THE
GEOGRAPHIC CONCENTRATION OF THE AFFECTED AREA
PLAYS A SIGNIFICANT ROLE IN THE DESIGN PROCESS.
 IGNORING THE TECHNICAL FACTORS IN THE CONSTRUCTION
MAY RESULT UNSATISFIED DESIGN.

4. GUIDING PRINCIPLES FOR HOUSING DESIGN &
CONSTRUCTION TECHNOLOGY
 THE HOUSING DESIGN & CONSTRUCTION TECHNOLOGY( HDCT’s)
USED IN THE CONSTRUCTION SHOULD BE SELECTED BY TAKING
CONSIDERATION LOCAL BUILDING PRACTICES, DESIRED
STANDARDS, CULTURE, ECONOMIC & CLIMATIC CONDITIONS.
 THE HDCT’s USED IN THE CONSTRUCTION MAY AFEECT PRICES &
SUPPLY IN THE BUILDING MATERIALS MARKET
 LOCAL EXPERTISE IS INVALUABLE IN SELECTING HDCT’s BUT IF
CHANGES ARE NEEDED TO IMROVE THAN BUILDER SHOULD BE
SUPPRTED BY BEST TRAINEES.
 A STRUCTURE DURING ITS LIFE SPAN FROM CONSTRUCTION TO
MAINTAINENCE SHOULD BE CONSIDERED IN USING BEST TYPE OF
TECHNOLOGY OPTIONS.
 REPAIRING & RETROFITTING PARTIALLY DAMAGED HOUSE ARE
ALTERNATIVE TO FULL CONSTRUCTION BUT DESERVE SIMILLAR
ATTENTION TO IMROVE THEIR STATE.

5. AVAILABLE CONSTRUCTION TECHNOLOGY &
BUILDING MATERIALS THAT DISCOVERED OVER
2 – 3 DECADES
 FOUNDATION: THE FOUNDATION DESIGN, FOR BUILDINGS
SHOULD BE ON THE BASIS OF THE TOTAL LOAD COMING AT A GIVEN
POINT AND THE BEARING CAPACITY OF THE SOIL. BUT NOW THERE IS
A TENDENCY TO OVER DESIGN FOUNDATION WITHOUT CONSIDERING
SOIL PROPERTIES.
 UNDER REAMED PILED FOUNDATION: THEY ARE USED IN LOOSE
& WEAK SOIL WHERE BEARING CAPACITY OF SOIL IS SO POOR. BY
CENTRAL BUILDING RESEARCH INSTITUTE PILED FOUNDATIONS
FOUND TO BE CHEAP & SUITABLE IN SUCH CONDITIONS. MOSTLY
USED IN BLACK COTTON SOIL.
 LEAN CONCRETE 1: 8: 16 : USUALLY PROPORTION USED FOR
FOUNDATION CONCRETE IS 1:4:8. BUT IT IS EXPERIMENTED THAT MIX
CAN BE LEANER FOR THE BEDS. NBO RECCOMED THE PROPORTION
1:8:16 LEAN CONCRETE FOR THE FOUNDATION BEDS.
 BRICK CAVITY WALLS: A BRICK CAVITY WALL IS MADE UP OF 2
INDEPENDENT BRICK MASONARY WALL EACH 7.5CM TH. WITH AN AIR
GAP BETWEEN THEM. THE WALL GAPS ARE TIED TOGETHER WITH
METAL BRICKS OR CONCRETE BLOCKS. IT REDUCES THE WEIGHT OF
THE WALL MAKING POSSIBLE LESSER SIZE OF BEAMS, COLUMNS
ETC. IT ALSO IMPROVES THERMAL QULAITY OF SPACE.

6.  MODULAR BRICKS: OCCUPIES LESSER FLOOR AREA & INCREASE IN THE
HEIGHT OF BRICK AS 7-9CM, THE NO. OF JOINTS IS REDUCED WHICH REDUCE
THE CONSUMPTION OF MORTAR.
 LOAD BEARING WALLS FOR MULTISTORIED BUILDINGS: WHEN THE NO.
OF FLOORS EXCEEDS 3-4 IT INCREASES THE THICKNESS OF WALL IN LOWER
AREAS. BUT IF GOOD QULATIY OF BRICK IS USED THAN SINGLE BRICK
THICKNESS WALL CAN BE ADOPTED UPTO 4-5 FLOORS .THE THICKNESS OF
MASONRY WALLS DEPENDS ON VARIOUS FACTORS LIKE STRENGTH OF BRICK
AND THE MORTAR USED, UNSUPPORTED HEIGHT AND LENGTH OF WALLS,
ECCENTRICITY IN VERTICAL LOADING, LOCATION AND SIZE OF THE OPENINGS
AND POSITION OF INNER CROSS WALLS.
 STONE BLOCK MASONARY: CASTING OF BLOCKS CAN BE DONE BY
SEMISKILLED WORKERS, WALL THICKNESS IS ALSO REDUCED THEREBY
SAVING IN MATERIALS AND LEADING TO LARGER USABLE FLOOR AREA ,
PLASTERING CAN BE ELIMINATED IF PROPER CARE IS TAKEN DURING
PRODUCTION AND LAYING.
 FERROW CEMENT :FERRO CEMENT IS VERSATILE FORM OF RCC MADE UP
OF CEMENT MORTAR(1:2) & WIRE MESH REINFORCEMENT & POSSESES
UNIQUE QUALITIES FOR STRENGTH & SERICEABILITY. FERRO CEMENT IS THIN
AND LIGHT AND THEREFORE REDUCES SELF WEIGHT, AS IT IS LIGHT, IT IS EASY
TO TRANSPORT FROM ONE PLACE TO ANOTHER, SAVING IN COST OF
FORMWORK, LESS CONSUMPTION OF STEEL AND CEMENT, EASY FOR REPAIRS
IN CASE OF ANY DAMAGE, GOOD FOR WATER TANKS, FRAMES FOR WINDOWS
AND DOORS, RAFTERS, SANITARY CORE UNITS, ROOFS ETC.
 FLYASH IN CEMENT COMPOSITES: FLYASH IS A PUZZOLANA MATERIAL
OBTAINED AS WASTE BYPRODUCT FROM THERMAL POWER PLANTS.
NORMALLY 10% TO 20% OF CEMENT CAN BE REPLACED BY 15%TO 27% OF
FLYASH . ADDING FLYASH REDUCES RESISTANCE TO CORROSION .

7.  LATO BLOCKS LATERITE SOIL IS WIDELY AVAILABLE IN MANY PARTS
OF INDIA. IT CONTAINS SILICA, ALUMINA AND FERROUS OXIDE. GOOD
QUALITY BLOCKS CAN BE MADE USING LATERITE SOIL. MATERIALS
LIKE LIME ARE ADDED TO IMPROVE QUALITY. BLOCKS ARE EITHER
STEAM CURED OR HOT WATER CURED. TESTED PROPERTIES ARE :
 WET COMPRESSIVE STRENGTH = 50 TO 15 KG/CM3
 NO WARPING
 MOISTURE ABSORPTION IS LESS THAN 12%
 GOOD PLASTERABILITY
 FIBRE REINFORCED CONCRETE
 FIBRE REINFORCED CONCRETE IS A TYPE OF CONCRETE MADE
FROM HYDRAULIC CEMENT WITH OR WITHOUT AGGREGATES OF
VARIOUS SIZES AND INCORPORATING FIBRE REINFORCEMENT. IF
NO AGGREGATE IS ADDED THE MATERIAL IS CALLED FIBRE
CEMENT WHICH IS SIMILAR TO ASBESTOS CEMENT. ASBESTOS
GLASS, STEEL AND CARBON FIBRES CAN BE USED TO
REINFORCE THE CEMENT MATRICES. THE MATERIAL IS USED
EXTENSIVELY FOR MANHOLE COVERS, SILOS, CONTAINERS,
CLADDING PANELS, PERMANENT FORMWORK ETC.

8. RELEVANCE & RECOMMENDATIONS :
 HOUSING DESIGN MAY BE INFLUENCED BY HOUSING
CONSTRUCTION TECHNOLOGY OR VICE VERSA.
 WHEN POSSIBLE THAN APPROPRIATE TRADITIONAL
TECHNOLOGIES. THEY OFTEN PROVIDE THE BEST SOLUTIONS
BY INTEGRATING COSTS, CLIMATE, CULTURE & TECHNICAL
CAPACITY.
 ADAPTAION OF TRADITIONAL WITH MODERN TECHNOLOGIES
MAKES THE SOLUTION APPROPRIATE.
 ASSESS & FACTOR INTO THE DESIGN AVAILABILITY OF LOCAL
MATERIALS & MANPOWER.
 IN MANY CASES REUSE & RECYCLING OF MATERIALS CAN BE AN
ALTERNATIVE SOURCE HOWEVER MEASURES MAY BE NEEDED
TO STORE, SORT & REPROCSS RUBBLE.

9. SEISMIC ISOLATION:
 SEISMIC ISOLATION IS A RELATIVELY NEW CONCEPT IN EARTHQUAKE
ENGINEERING, HAVING BEEN INTRODUCED IN THE EARLY 1980’s.
 MAIN CONCEPT : QUITE SIMPLY, THE IDEA UNDERLYING THE TECHNOLOGY IS
TO DEATCH THE BUILDING FROM THE GROUND IN SUCH A WAY THAT THE
EARTHQUAKE MOTIONS ARE NOT TRAMSMITTED UP TO THE BUILDING, OR ARE
GREATLY REDUCED
 PRINCIPLE: INTRODUCE FLEXIBLITY AT THE BASE OF THE STRUCTURE IN THE
HORIZONTAL PLANE, WHILE AT THE SAME TIME INTRODUCING DAMPING
ELEMENTS TO RESTRCIT THE AMPLITUDE OF THE MOTION CAUSED BY
EARTHQUAKE.
 THREE BASIC ELEMENTS IN SESMIC ISOLATION:
 A FLEXIBLE MOUNTING SO THAT THE PERIOD OF VIBRATION OF THE TOTAL
SYSTEM IS LENGTHENED SUFFICIENTLY TO REDUCE THE FORCE RESPONSE.
 A DAMPER OR ENERGY DISSIPATOR SO THAT THE RELATIVE DEFLECTIONS
BETWEEN BUILDING AND GROUND CAN BE CONTROLLED TO A PRACTICAL
DESIGN LEVEL.
 A MEANS OF PROVIDING RIGIDITY UNDER LOW (SERVICE) LOAD LEVELS, SUCH
AS WIND AND MINOR EARTHQUAKES.
 SEISMIC ISOLATION ACHIEVES A REDUCTION IN EARTHQUAKE FORCES BY
LENGTHENING THE PERIOD OF VIBRATION IN WHICH THE STRUCTURE
RESPONDS TO THE EARTHQUAKE MOTIONS
 THE MOST SIGNIFICANT BENEFITS OBTAINED FROM ISOLATION ARE THUS I
STRUCTURES FOR WHICH THE FUNDAMENTAL PERIOD OF THE BUILDING
WITHOUT ISOLATION IS SHORT—LESS THAN ONE SECOND

10. VERTICAL SECTION THROUGH A BASE ISOLATED BUILDING

11. • PASSIVE ENERGY DISSIPATION SYSTEMS REPRESENT AN
ALTERNATIVE TO SEISMIC
ISOLATION AS A MEANS OF PROTECTING BUILDING STRUCTURES
AGAINST THE EFFECTS OF DAMAGING EARTHQUAKES.
• THE BASIC FUNCTION OF PASSIVE ENERGY DISSIPATION DEVICES
IN A BUILDING IS TO ABSORB OR CONSUME A PORTION OF THE
EARTHQUAKE INPUT ENERGY, THEREBY REDUCING ENERGY
DISSIPATION DEMAND ON PRIMARY STRUCTURAL MEMBERS AND
MINIMIZING STRUCTURAL DAMAGE.
• THE MEANS BY WHICH THE ENERGY IS DISSIPATED IS EITHER
THROUGH THE YIELDING OF MILD STEEL, SLIDING FRICTION,
MOTION OF A PISTON OR A PLATE WITHIN A VISCOUS FLUID, MOTION
OF AN ORIFICE VISCOUS FLUID DEVICE, OR VISCOELASTIC ACTION
OF POLYMERIC MATERIALS.
• THE MOST COMMON TYPES OF PASSIVE DEVICES USED-TO-DATE
INCLUDE VISCOUS FLUID DAMPERS, FRICTION DAMPERS, METALLIC
DAMPERS, AND TUNED MASS DAMPERS THESE DEVICES CAN BE
EFFECTIVE AGAINST WIND MOTIONS AS WELL AS AGAINST
EARTHQUAKES.
PASSIVE ENERGY DISSIPATION DEVICES