COSTEFFECTIVE ARCHITECTURE

(REPORT ALTERNATIVE BUILDING MATERIAL AND WORKS OF LAURIE BAKER)

BY:GROUP-2ASECTION-C, 2nd year

INDEX

INTRODUCTION

NEED FOR ALTERNATIVEBUILDING MATERIALS

INTRODUCTION TO CSEB

MANUFACTURING SOIL IDENTIFICATION STABLIZER PROPORTION CURING COST ANALYSIS

INTRODUCTION TO PULVERISED ASH BRICKS MANUFACTURE ADVANTAGES PRICE PROFIT RATIO

INTRODUCTION TO PRESTRESSED CONCRETE TYPES ADVANTAGES DIRECT COST REDUCTION PERFORMANCE

INTRODUCTION TO BAMBOO ADVANTAGES USES EXAMPLE

INTRODUCTION TO FERRO-CEMENT CONSTITUENT ADVANTAGES COST EFFECTIVENESS APPLICATION

LAURIE BAKER INTRODUCTION TECHNIQUES FAMOUS WORKS INDIAN COFFEE HOUSE, TRIVANDRUM

AUROVILLE EARTH INSTITUTE, TAMIL NADU BUILDING TECHNOLOGY USE OF RAMMED EARTH ENERGY EFFECTIVENESS COST EFFECTIVENESS

NEED FOR ALTERNATIVE BUILDING MATERIALS:

Demand for new buildings as well as the cost of building construction is growing at a steady pace.

Bricks, cement, steel, timber, plastics, glass, are some of the commonly used conventional materials .

Manufacturing processes are detrimental to the environment.

Use of conventional materials alone to satisfy the demand for new buildings, can drain the available energy resources and causeenvironment degradation.

Center for ASTRA (Application of Science and Technology to Rural Areas) formed in the Indian Institute of Science, Bangalore, has developed alternative building technologies looking at utilization of local materials and reducing energy consumption to achieve cost reduction.

INTRODUCTION TO CSEB:-

Soil Cement Blocks or Compressed Stabilized Earth Blocks (CSEB) are dense solid blocks compacted using a machine with a mixture of soil, sand, stabilizer(cement/lime) and water.

Standard sizes are (305x143x100mm) and (230x190x100mm).

AT 7% of cement the wet compressive strength of 3-4Mpa. can be obtained.

CSEB can be used for wall construction without any new technological problems.

The Soil cement blocks can be constructed using cement mortar, lime mortar, lime pozzolana mortar or mud mortar.

Normal cement mortar of 1:6 proportions has been used in the construction of soil-cement block walls of several buildings. To improve the bonding frogs have been introduced on both faces.

MANUFACTURING PROCESS:

Soil Suitability and Stabilization for CSEB

Not every soil is suitable for CSEB in particular. Top soil and organic soils must not be used.

A good soil forCSEB is more sandy than clayey.

Soil Identification:

Grain size distribution, to know quantity of each grain size.

Plasticity Characteristics, to knowthe quality and properties of the binders(clay and silts)

Compressibility, toknow the optimum moisture content ,which will require minimum of compaction energy for the maximum density.

Cohesion, to know how thebinders bind the inert grains.

Humus content to know if thereare organic materials which might disturb the mix.

Stabilizer proportion: Cement stabilization = 5% average The minimum is 3% and the maximum is 8%

Lime stabilization = 6% average

The minimum is 2% and the maximum is 10%

Curing:

The mud blocks stabilized with cement or lime must be cured for 21 days by a gentle sprinkling of water. The top of thestack of blocks must be covered by straw or gunny cloth to prevent evaporation ofwater. After 28 dayscuring, the stabilized mud blocks (SMB)are used forwall construction

TEST RESULTS, COST ANALYSIS:

Change in compressive strength with extra pressure and extra cement

WORKS DONE:BUILDING WITH EARTH IN AUROVILLE

Building with arches, vaults and domes1. Training Centre of AV-BC With stabilized earth Waterproofing

2. Mirramukhi School

10.35 m span Builtin3weeksINTRODUCTION TO PULVERISED ASH BRICK:-

Pulverised ash brick (PAB) technology is a process ofconverting industrial waste materialsinto quality building materials. At present, the technology is well established in converting thermal power plant wasteinto quality bricks.

PAB technology usesdry ash(fly ash collected from ESP or silos of thermal power plants);filler materials(usually coarse sand or stone crusher dust); andadditives(lime, gypsum or cement). The strength of the bricks can be engineered by varying compositions. Equipment used can be manual or mechanized. Mechanized machines deploy hydraulic compaction to produce a variety of bricks and can be operated through electric or diesel power.

PROCESS OF MANUFACTURE:

Fly ash, Hydrated lime, Quarry dust and gypsum are manually fed into a pan mixer where water is added in the required proportion for intimate mixing. The proportion of the raw material is generally in the ratio

62%fly ash

8%lime

5%Gypsum

25%Quarry Dust

depending upon the quality of raw materials.After mixing, the mixture is shifted to the hydraulic Brick Making machines. The bricks are carried on wooden pellets to the open area where they are dried and water cured for 14 days. The bricks are tested and sorted before dispatch.

FLYASH BRICKNORMAL CLAY BRICK

Uniform pleasing colour like cementVarying colour as per soil

Uniform in shape and smooth in finishUneven shape as hand made

Dense compositionLightly bonded

No plastering requiredPlastering required

Lighter in weightHeavier in weight

Compressive strength is around 100 Kg/cm2Compressive strength is around 35 Kg/cm2

Less porousMore porous

Thermal conductivity 0.90-1.05 W/m2 CThermal conductivity 1.25 1.35 W/m2 C

Water absorption 6-12%Water absorption 20-25%

PRICE PROFIT RATIO FaL-G Bricks (Fly ash)(Without Cement):

Fly ash Bricksmade from fly ash, gypsum, sand or stone dust is turning to a highly profitable business in India and all around the world.

Fly ash, the raw material for fly ash bricks is available at very low cost from Thermal power stations.

Fly ash - Rs 100 per tonin Tamilnadu Thermal power stations. Transport charges extra.

INTRODUCTION TO PRESTRESSED CONCRETE:

Prestressed concreteis a method for overcomingconcrete's natural weakness intension. It can be used to producebeams,floorsor bridgeswith a longerspanthan is practical with ordinaryreinforced concrete. Prestressing tendons (generally of hightensilesteelcableor rods) are used to provide a clamping load which produces acompressive stressthat balances thetensile stressthat the concrete compression memberwould otherwise experience due to a bending load. Traditionalreinforced concreteis based on the use ofsteel reinforcement bars,rebars, inside pouredconcrete. Prestressing can be accomplished in three ways: pre-tensioned concrete, and bonded or unbonded post-tensioned concrete.Prestressed concrete is a when cables are placed in the concrete to combat the tensile forces created when weight is put on concrete. There are two ways in which this is done: pretensioning and post-tensioning. In pretensioning the cables are stretched before the concrete is cast, in post-tensioning, the cables are stretched after the concrete has hardened. The advantages are the elimination of cracking in concrete, reduced cross section of members, reduced weight of member, less concrete is needed, longer spans are possible, and there is greater recovery after overloads. The disadvantages are only the highest quality of materials can be used, closer control is needed, skilled workmen are required, greater capital investment for prestressing equipment is needed and the high cost of end anchorage units (in post-tensioned work).TYPES OF PRESTRESSED CONCRETE: Pre-tensioned concreteIn pretensioning, the steel is stretched before the concrete is placed. High-strength steel tendons are placed between two abutments and stretched to 70 to 80 percent of their ultimate strength. Concrete is poured into molds around the tendons and allowed to cure. Once the concrete reaches the required strength, the stretching forces are released. As the steel reacts to regain its original length, the tensile stresses are translated into a compressive stress in the concrete. Typical products for pretensioned concrete are roof slabs, piles, poles, bridge girders, wall panels, and railroad ties. Post-tensionedIn post-tensioning, the steel is stretched after the concrete hardens. Concrete is cast around, but not in contact with unstretched steel. In many cases, ducts are formed in the concrete unit using thin walled steel forms. Once the concrete has hardened to the required strength, the steel tendons are inserted and stretched against the ends of the unit and anchored off externally, placing the concrete into compression. Post-tensioned concrete is used for cast-in-place concrete and for bridges, large girders, floor slabs, shells, roofs, and pavements.

ADVANTAGES: Longer spans Unique designs: irregular shapes Shorter construction cycles Cost reduction Shorter floor-to-floor heights Superior structural performance

DIRECT COST REDUCTION:Post-tensioning offers direct cost reduction over conventionally reinforced slabs primarily by reducing concrete and rebar material quantities as well as rebar installation labor. Typically, savings between 10%20% in direct cost are achieved.

Followings are the factors which contribute to direct cost reduction: Less concrete material Reduction in slab thickness reduces total building height and cost Less rebar Less labor cost for installation of material Reduced material handling

Improved Construction Efficiency:Since post-tensioned slabs are designed to carry their own weight at time of stressing, they can significantly improve construction efficiency and deliver an additional 5%-10% of indirect savings.

Following factors contribute to improved construction efficiency: Shorter construction cycles Less material handling and impact on other trades Simpler slab soffitless beams and drop caps/panels Quicker removal of shoring gives more access to lower slabs Typical 5-Day Construction Cycle schedule for 800-1,000 m2of slab is shown below. 3-day cycle is also achievable with early strength concrete and industrial formwork.

SUPERIOR STRUCTURAL PERFORMANCE:The prestressing in post-tensioned slabs takes optimal advantage of tendon, rebar and concrete properties to deliver an economical structural system.

Factors contributing to superior structural performance are listed here: Use of high-strength materials Deflection control Longer spans are achieved.

INTRODUCTION TO BAMBOO:-The world timber demand is increasing at a rapid rate but the timber supply is depleting. Its been found through research that bamboo can suitably replace timber and other materials in construction and other works. Industrially treated bamboo has shown great potential for production of composite materials and components which are cost-effective and can be successfully utilized for structural and non-structural applications in construction. Bamboo is one of the oldest traditional building materials used by mankind.There are also a number of other benefits to choosing bamboo solutions over wood including: Strength and Durability: Bamboo is heartier than oak and stronger than steel. It is flexible and lightweight, and is water-resistant, minimizing the risk for warping2and Affordability: It is easily grown and harvested, making it one of the most cost effective construction materials available.

ADVANTAGES:Bamboo cultivation has a wide array of advantages, including: Reducing cost per uses of bamboo Increasing jobs 35% higher oxygen emission into the atmosphere than trees 40% more CO2 absorption than trees No fertilizer or pesticides required for growth Establishing an extensive root system into soils, which in turn draws in and stores double the amount of water into watersheds, thus preventing soil erosion.

USES:Internal Uses for Bamboo: Flooring Support columns Electrical wire coverings Interior walls Eco-friendly products for kitchen and bath

External Uses of Bamboo: Structural frames Corner posts Girders Joists Studs Braces Tie beams King posts Purlins Ridgepoles

BAMBOO AS CONSTRUCTION MATERIAL:

Through research it has been found that some species of bamboo have ultimate tensile strength same as that of mild steel at yield point and this coupled with other merits boosts the usage of bamboo as construction material.Bamboo is a versatile material because of its high strength-to-weight ratio, easy workability and availability. Bamboo needs to be chemically treated due to their low natural durability. It can be used in different ways for roof structure as purlins, rafters and reapers, forflooring, doors and windows, walling, ceiling, man-hole covers.

Bamboo Trusses:The bamboohas strength comparable to that of teak and sal. An experiment with the construction and testing of a 4m span truss made of round bamboo and different jointing techniques for web-chord connections gave results that were matching with the strength of timber.

Bamboo Roofs Skeleton:It consists of bamboo truss or rafters over which solid bamboo purlins are laid and lashed to the rafter by means of G.I.wire. A mesh of halved bamboo is made and is lashed to the purlins to cover the roof.

Bamboo walling/ceiling:Asthe bamboomaterial is light in weight it is more advantageous in earthquake prone areas as its chances of falling are very less and even if it falls it can be re-erected easily with less human and property loss with least efforts and minimum cost. Bamboo walls can be constructed in different modes likeWhole stem, halved or strips of bamboo can nailed to one or both the sides ofthe bambooframeSplitbamboo mats can be fastened tothe bambooposts or mats can be woven, mud can also be applied to both sides of such matsBamboo strips nailed to bamboo frame or posts for interior wallingCement or lime plastering can be done on the mud covering for better appearance and hygiene.It has been found that the bamboo in the vertical position is more durable than in horizontal direction. For partition walls only single layer of bamboo strips are used. Bamboo Doors and Windows:Bamboo frames can replace timber frames appropriate to function. Bamboo mat shutters fixed to bamboo frame or a panel of bamboo board fixed to the frame which is hinged to the wall can be used as door. Small framed openings hinged to the top in the wall can serve as windows.

Bamboo Flooring:Bamboo can be used as flooring material due to its better wear and tear resistance and its resilience properties. Whole culms act as frame work and the floor covering is done using split bamboo, bamboo boards, mats etc by means of wire lashing these to the frame.

Reed Boards:Reed boards are made by flat pressing the reed at high temperatures. These reed boards are used in elements like flooring, walls, ceiling and roofing. They can also be used for partitions, doors, windows etc. Scaffolding:Bamboo poles lashed together have been used as scaffolding in high rise structures due to their strength and resilience. The timber planks can be replaced with bamboo culms and these can be lashed to the vertical culms.

EXAMPLE:Green Building Features in India Pavilion:The following green building features have been included in the construction:i. Site selection though ITPO had no control over it as there is no cutting or scouring effect in the area.ii. Architectural concept of open veranda and courtyardiii. Energy efficiency through ventilation and dome shaped structureiv. Rain water harvestingv. Recycling of water, through which green plants will be irrigated.vi. Wind millvii. Solar panelsviii. Use of bamboo which resulted in saving of steel and cementix. Use of natural materials like terracotta and bamboo in false ceiling and benchesx. Use of ferrocement and plants on top of dome which will result in energy efficiency by reduction in air conditioning load.xi. Plantation of grown up trees and plants in the area.xii. Use of bricks in flooring in open spacesxiii. Use of natural materials like thatch over roof of the vault.xiv.

INTRODUCTION TO FERRO-CEMENT:-Ferrocement, also referred to as ferro concrete orreinforced concrete, a mixture of Portland cementand sand applied over layers of woven or expanded steel mesh and closely spaced small-diameter steel rodsrebar. It can be used to form relatively thin, compound-curved sheets of concrete ideal for such applications ashullsfor boats, shell roofs, and water tanks. It has a wide range of other uses including sculpture and prefabricated building components. The term "ferrocement" has been applied by extension to othercomposite materials, including some containing no cement and no ferrous material.

Typical cross section of ferro-cement structure.Constituent Materials: Cement Fine Aggregate Water Admixture Mortar Mix Reinforcing mesh Skeletal Steel Coating

Advantages: Basic raw materials are readily available in most countries. Fabricated into any desired shape. Low labour skill required. Ease of construction, low weight and long lifetime. Low construction material cost. Better resistance against earthquake.

Cost Effectiveness of Ferro-cement Structures: The type of economic system. Type of applications. Relative cost of labour. Capital and local tradition of construction procedure. Doesnt need heavy plant or machinery. Low cost of construction materials.Recent Applications: Residential and Public Buildings

Transportation Structures

Industrial Structures

LAURIE BAKER

Introduction Born(1917-03-02)2 March 1917Birmingham, England

Died1 April 2007(2007-04-01) (aged90)Thiruvananthapuram, Kerala, India

NationalityIndian

AwardsPadma Shri, MBE

renowned for his initiatives in cost-effective energy-efficient architecture and for his unique space utilization and simple but aesthetic sensibility. Influenced by Mahatma Gandhi, he sought to incorporate simple designs with local materials and achieved fame with his approach to sustainable architecture as well as in organic architecture. He has been called the "Gandhi of architecture. He founded COSTFORD (Centre of Science and Technology for Rural Development), an organization to promote low-cost housing.

Construction Techniques: Laurie Baker lived and practiced architectural principles of cost-effectiveness, use of locally available materials, respect for nature, avoidance of energy-intensive materials and wastage minimization to create beautiful, high quality, cost-effective buildings which conformed to concepts such as eco-friendliness and sustainable architecture; decades before these concepts became mainstream considerations in the built environment.

Some Of His Works:1. Institutions and Buildings

Leprosy homes for Mission to Lepers across IndiaPithoragarh house, school and hospital complexNepal HospitalAllahabad Agricultural UniversityLucknow Psychiatric Centre, Noor ManzilLiteracy Village, LucknowCentre for Social Studies, SuratAhmedbad & Baroda factoriesJyothi Pumps, BarodaChildrens Village, 1965, Kulashekaram, Tamil NaduMitraniketan , VagamonHorst Kowski orphanages and homes across India (other than Childrens Village Nagercoil)Houses for the Archbishop of TrivandrumTourist Resort near MuttamLoyola Womens Hostel, 1970, SreekaryamLoyola Chapel and Auditorium, 1971, SreekaryamCentre for Development Studies (CDS), 1971, UlloorSt Johns Cathedral, 1973, Thiruvella

Residences:

Jayan and Asha, KakkanadNeetas HouseHUDCO SureshIAS ColonyAbu Abraham, 1989Major Jacob, 1988, KulasekharamLeela Menon, 1973Mr. Narayans Mango houseVellayaniA M JacobAnirudhin 1969 first house in Trivandrum to have a preponderance of jalisNambudiripaad, 1973, KEsavadasapuramNalini, 1989, AnayarKN Raj, 1970, KumarapuramTN Krishnan, 1971, KumarapuramPK Panikar, 1974, KumarapuramVaidyanathan, 1972, KumarapuramT C Alexander, 1982, Vikramapuram HillP J Thomas, 1972, KuravankonamLt Gen Pillai, 1971, Jawahar NagarP Ramachandran, 1975, PottakuzhyRavindranath, 1975, GourishapattomVarghese Jacob, 976, KottayamK V George, 1987, KarakullamVasanth Gawerekar, 1982, ManvilaBeena Sarasan, 1989, Kowdiar

About One Of His Renowned Structures LAURIE BAKER'S INDIAN COFFEE HOUSE, TRIVANDRUM: Now although the building is unique in design, there are a few functional issues. Due to the placement of the kitchen on the ground level, it becomes difficult for the serving staff as they have to continuously climb up and down the ramp to place the orders & then to serve the people sitting on the upper levels. Thus, they in fact ask the customers to occupy the lower seating first before going up the spiral. The entire building is conceived as a continuous spiral ramp, with a central circular service core and with dining spaces provided on the outer side. The form of the building is thus unconventional & bears Bakers trademark jaalis to let in light & ventilation. The building is well proportioned, a cylindrical brick-red spiral continuing for a couple of floors and then terminating in a smaller cylindrical volume on top, giving a very unsymmetrical balance to the whole structure.

Negatives Of The Structure Now although the building is unique in design, there are a few functional issues. Due to the placement of the kitchen on the ground level, it becomes difficult for the serving staff as they have to continuously climb up and down the ramp to place the orders & then to serve the people sitting on the upper levels. Thus, they in fact ask the customers to occupy the lower seating first before going up the spiral.

Low Cost Construction: Rat trap bond Rat trap bond brick masonry is an alternative to normal English bond masonry walls by which 15% of cost can be reduced without comprimising the quality, strength and appearances. Baker creates a variety of textures and patterns by simple manipulation of the way in which bricks are placed in the wall.

Filler slabs

Filler slabs employ replacing 'un-productive' concrete by a 'Filler' material which reduces the weight of the slab and also the cost by reducing the amount of concrete used. Also, since the weight of the slab is thus reduced, lesser steel is required for reinforcement, further reducing the cost.

AUROVILLE EARTH INSTITUTE,TAMIL NADURaw earth for building has been used worldwide for millennia but during the 20thcentury most of the skills of earth builders were lost and building with earth became marginal. Through the endeavour of the Auroville Earth Institute, Auroville is today reviving these traditional skills and demonstrating that earth is a noble building material which can be used for manifesting modern, harmonious and progressive architecture for the third millennium.Most of the projects are built with compressed stabilised earth blocks (CSEB), as this technology benefits of more than half a century of research and development worldwide. There are also three other earth techniques used in Auroville. These techniques are very marginally used as only about 10 buildings have been built with them: Raw rammed earth Adobe blocks, the traditional sun dried mud brickWattle and daub which is mud plastered on a wattle made of split bamboo or palmyra tree.

APPROPRIATE BUILDING TECHNOLOGIES BASED ON EARTH:This research aims at making extensive use of raw earth as the main building material, thereby using a local resource to help develop technologies that are energy saving, eco-friendly and sustainable.The main research and development is focussed on minimising the use of steel, cement and reinforced cement concrete (RCC). Training Centre of the Auroville Earth Institute is constructed entirely with stabilised earth, from the foundations to the waterproofing: Stabilised rammed earth foundations (with 5 % cement) Stabilised rammed earth walls (with 5 % cement and a homeopathic milk of lime and alum) Composite columns (round and hollow CSEB with reinforced concrete) Composite beams (U shape CSEB with reinforced concrete) Stabilized earth mortars and plasters Wide variety of compressed stabilised earth blocks (17 moulds are presently available for producing about 75 different types of blocks) Various vaults with compressed stabilised earth blocks Alternative stabilizers to cement (homeopathic milk of lime and alum) Alternative waterproofing with stabilized earth (various mixes of soil, sand, cement, lime, alum and juice of a local seed).

STABILISED RAMMED EARTH:In Auroville, the earth is rammed by hand. Until 1994, Auroville had only one house made of raw rammed earth. Stabilised rammed earth was promoted since 1995, after the construction of Mirramukhi School (presently named Deepanam). Stabilised rammed earth presents the advantage of being cheaper than compressed stabilised earth blocks.

ENERGY EFFECTIVENESS:Costs are too often limited only to a monetary value. Another important aspect is the environmental cost, especially with the embodied energy into the material. The initial embodied energy of CSEB is about 4 times less than country fired bricks. Of course the carbon emission is also about 4 time less for the CSEB, compared to the country fired bricks.Initial embodied energy (MJ/m3of materials)CSEB are consuming 4 times less energy than country fired bricks:CSEB produced on site with 5 % cement = 1,112.36 MJ/m3Country fired bricks = 4,501.25 MJ/m3

Carbon emission (Kg of CO2 /m3of materials)CSEB are polluting 4 times less than country fired bricks:CSEB produced on site with 5 % cement = 110.11 Kg of CO2 /m3Country fired bricks = 444.12 Kg of CO2 /m3

COST EFFECTIVENESSEarthen buildings have the advantage of using local resources and being labour intensive. Therefore, most of the time, they cost less than conventional materials and technologies. The final cost of a building will depend mainly on the design, the type of finishes and the project management. In all cases, the technologies implemented are cost effective.