Bricks projects

Ø  A brick is building material used to make walls, pavements and other elements in masonry construction.

Ø  Traditionally, the term brick referred to a unit composed of clay, but it is now used to denote any rectangular units laid in mortar.

Ø  A brick can be composed of clay-bearing soil, sand and lime, or concrete materials.

Ø  Bricks are produced in numerous classes, types, materials, and sizes which vary with region and time period, and are produced in bulk quantities.

Ø  Two basic categories of bricks are fired and non-fired bricks.

Ø  Fired bricks are one of the longest-lasting and strongest building materials, sometimes referred to as artificial stone, and have been used since circa 5000 BC.

Ø  Air-dried bricks, also known as mud bricks, have a history older than fired bricks, and have an additional ingredient of a mechanical binder such as straw.

Ø  Bricks are laid in courses and numerous patterns known as bonds, collectively known as brickwork, and may be laid in various kinds of mortar to hold the bricks together to make a durable structure.

Ø  Bricks are one of the oldest known building materials dating back to 7000BC where they were first found in southern Turkey and around Jericho.

Ø  The first bricks were sun dried mud bricks. Fired bricks were found to be more resistant to harsher weather conditions, which made them a much more reliable brick for use in permanent buildings, where mud bricks would not have been sufficient.

Ø  Fired brick were also useful for absorbing any heat generated throughout the day, then releasing it at night.

1.2 CEMENT BRICKS

Cement bricks have an important place in modern building industry. They are cost effective and better alternative to burnt clay bricks by virtue of their good durability, fire resistance, partial resistance to sound, thermal insulation, small dead load and high speed of construction.

                                                                                         

Cement bricks being usually stronger than the normal clay building bricks and less mortar is required, faster of construction is achieved. Also building construction with cement bricks provides facility for concealing electrical conduit, water and sewer pipes wherever so desired and requires less plastering.

1.3 OVERVIEW OF RICE HUSK ASH

The Rice Husk Ash (RHA) is obtained from burning of rice husk. Rice mill generates the by-product husk as well as rice husk ash. This husk contains about 75 % organic volatile matter and the balance 25 % of the weight of this husk is converted into ash during the firing process, is known as rice husk ash (RHA).

So for every 1000 kgs of paddy milled, about 220 kgs (22 %) of husk is produced, and when this husk is burnt in the boiler, about 55 kgs (25 %) of RHA is generated.

1.4 OVERVIEW OF SUGARCANE BAGASSE ASH

            The Sugarcane Bagasse Ash (SCBA) is obtained from burning sugarcane bagasse as well as from Sugar Industry. In general sugarcane industries runs their boilers by burning bagasse to generate electricity. The sugar industries by product is the Sugarcane bagasse ash.

Every 35 kg of sugarcane bagasse produces 2.65 kg of sugarcane bagasse ash.

1.5 OVERVIEW OF CHICKEN FEATHERS ASH

            The Chicken Feathers Ash (CFA) is obtained from burning of chicken feathers, which is by-product of broiler chicken centre all over the world and these feathers are spread over the vast land as solid waste.

            These feathers are also biodegradable but the effect of chicken feathers causes many disease like virus fever. So it can be utilised in the manufacturing of Cement Bricks.

1.6 AMOUNT OF RICE HUSK, SUGARCANE BAGASSE AND CHICKEN FEATHERS ASH PRODUCED IN INDIA PER YEAR

            The amount of rice husk ash produced in India and Tamilnadu is tabulated below.

RICE (Production in lakhs tonnes)
AREA	HUSK	ASH
INDIA	220	55
TAMILNADU	13.2	3.3

Table 1.1 Rice husk Ash Production

SUGARCANE (Production in million tonnes)
AREA	BAGASSE	ASH
INDIA	90	6.3
TAMILNADU	10	0.7

Table 1.2 Sugarcane Bagasse Ash Production

CHICKEN (Production in lakhs tonnes)
AREA	FEATHERS	ASH
INDIA	150	46
TAMILNADU	80	2

Table 1.3 Chicken Feathers Ash Production

1.7 MARKET & DEMAND ASPECTS

Cement bricks are modern construction materials and as such are used in all the constructions viz. residential, commercial and industrial building constructions. Construction industry is a growing a sector.

The demand for this product is always high in all cities and other urban centres due to construction of residential apartments, commercial buildings and industrial buildings.

Growing public awareness of the advantages of the product coupled with Increase in the government and financial institutions support for housing which is a basic human necessity would ensure a healthy growth in the demand.

LITERATURE REVIEW

2.1 GENERAL

            The ashes are used in the project is RHA, SCBA and CFA. The Rice Husk Ash is produced from the rice mill while burning. The Sugarcane Bagasse Ash is produced from the sugar industry, which is used for producing electricity from the boilers. While bagasse burning it becomes ashes. The Chicken Feathers Ash is obtained from the Broiler chicken centre and it can be burned manually to produced ashes.

2.2 CHARACTERISTIC OF ASH

2.2.1 RICE HUSK ASH PROPERTIES

Studies have shown that RHA resulting from the burning of rice husks at control temperatures have physical and chemical properties that meet ASTM (American Society for Testing and Materials) Standard C 618-94a. 

At burning temperatures of 550 ⁰C – 800 ⁰C, amorphous silica is formed, but at higher temperatures crystalline silica is produced.  The silica content is between 90 and 96%. 

The particular chemical and physical properties are given in Table 2, and Fig. 1 shows the X-ray diffraction analysis, which indicates that the RHA mainly consists of amorphous materials (Bouzoubaa, and Fournier 2001). 

Grinding for producing high quality RHA was studied by (Loo et al. 1984).  Studies have shown that to obtain the required particle size, the RHA needs to be grown to size 45 μm – 10 μm.

2.2.2 SUGARCANE BAGASSE ASH PROPERTIES

The sugarcane bagasse consists of approximately 50% of cellulose, 25% of hemicelluloses and 25% of lignin. Each ton of sugarcane generates approximately 26% of bagasse (at a moisture content of 50%) and 0.62% of residual ash.

The residue after combustion presents a chemical composition dominates by silicon dioxide (SiO2). In spite of being a material of hard degradation and that presents few nutrients, the ash is used on the Farms as a fertilizer in the sugarcane harvests.

2.3 LITERATURE REVIEW

2.3.1 EARLIER STUDIES ON RICE HUSK ASH

Mehta, P.K., has conducted investigations on Portland Rice Husk Ash cements up to 50% of Ash showed higher compressive strength than the control Portland cement even at as early as 3 days.

Mehta, and Pirtz in a concrete mixture, when 30% Rice Husk Ash by weight of the total cementing material was present, the 7 days and the 28 days compressive strengths were higher.

Subba Rao.et.al studied the reaction product of lime and silicate from Rice Husk Ash and showed that it is Calcium Silicate Hydrate (CS-H) which accounts for the strength of lime Rice Husk Ash cements.

The use of RHA will contribute not only, to the production of concrete of a higher quality and lower cost, but also the reduction of carbon dioxide (CO₂) emissions from the production of cement. 

The partial replacement of cement by RHA will result in lower energy consumption associated with the production of cement.  The market potential for rice husk-to-energy systems and equipment has been studied by Velupillai et al. (1997). 

The reference also addresses economic development, urbanization, higher living standards, tighter environmental regulations, and consolidation in the rice milling industry are reducing some of the traditional uses of husks, and creating new opportunities for husk utilization.

Ajay kumar et al Rice husk has been used directly or in the form of ash either as a value added material for manufacturing and synthesizing new materials or as a low cost Substitute material for modifying the properties of existing products.

Presence of silica is an additional advantage in comparison to other by-product materials which makes RH an important material for a wide range of manufacturing and application oriented processes.

Easy availability and low price of rice husk in rice producing countries is an extra benefit towards the use of this material. Despite having high potential and suitability in so many well established uses, use of rice husk has been limited.

In the competitive market, proper Utilization of rice husk and its ash will benefit industrial sectors. The use of rice husk as fuel/electricity generation in efficient manner is likely to transform this agricultural waste material in to a valuable fuel for industrial sectors.

A systematic approach to this material can give birth to a new industrial sector of rice husk.

2.3.2 EARLIER STUDIES ON SUGARCANE BAGASSE ASH

Apurva KulkarnI et al. Compressive strength decreases on increase in percentage of Bagasse ash as compare to fly ash. Use of bagasse ash in brick can solve the disposal problem; reduce cost and produce a ‘greener’ Eco-friendly bricks for construction.

Environmental effects of wastes and disposal problems of waste can be reduced through this research. A better measure by an innovative Construction Material is formed through this research.

It provides innovative use of class F fly ash which contains less than 20% lime. This study helps in converting the non-valuable bagasse ash into bricks and makes it valuable. In this study, maximum compressive strength is obtained at 10% replacement of fly ash as bagasse ash. Bagasse ash bricks reduce the seismic weight of building.

Anil Pratap Singh et al. Replacement of sand with SBA resulted in lower weight of the bricks. Therefore produce light weight bricks.

In terms of compressive strength (SBA-SAND-CEMENT) bricks are satisfy the requirement of (I.S 1077(BIS-1992d)).So it is suitable for another alternative material.

To protect the clay resources and environment by using these bricks in structural building, the builder saves around 15 to 20% of structural steel and concrete as these bricks reduce the dead load on the building.

 Ajay Goyal Ashes obtained after control burning of SCB at 600oC/5hour were reasonably reactive given by the fact that little crystallization of minerals occurred. Morphological, XRD and TGA/DTA study of the blended pastes confirmed the hydration reaction of SCBA with in the cement gel.

Compressive and flexural strength tests confirmed the actual behaviour of SCBA blended mortars and it suggested that up to 15% substitution of OPC with SCBA can be made with better strength results than that with pure cement.

EXPERIMENTAL WORK

4.1 GENERAL

At this time India is witnessing a new phase in development. With rapid economic growth and high rate of urbanisation. Construction provides the direct means for the development, expansion, improvement and maintenance of human settlements is particular and economic growth in general. Construction activity accounts for more than 50% of the development outlays in India. Building construction costs are increasing at rates which are so per cent over inflation.

The primary raw material used for bricks is the soil, which is often taken from prime agricultural land, causing land degradation as well as economic loss due to diversion of agricultural land. Use of traditional technologies in firing the bricks results in significant local air pollution. The burnt clay brick industry in India produces over 180 billion clay bricks annually with a strong impact on soil erosion and unprocessed emissions.

4.2 REQUIREMENTS OF FLY ASH LIME BRICKS AS PER IS 12894: 2002

4.2.1 GENERAL REQUIREMENT

Ø  Visually the bricks shall be sound, compact and uniform in shape. The bricks shall be free from visible cracks, war-page and organic matters.

Ø  Hand-moulded bricks of 90 mm or 70 mm height shall be moulded with a frog 10 to 20 mm deep on one of its flat sides.

Ø  Bricks of 40 or 30 mm height as well as those made by extrusion process may not be provided with frogs.

Ø  The bricks shall be solid and with or without frog 10 to 20 mm deep on one of its flat side.

Ø  The bricks shall have smooth rectangular faces with sharp corners and shall be uniform in shape and colour.

4.2.2 DIMENSIONS AND TOLERANCES

The standard modular sizes of pulverized fuel ash-lime bricks shall be as following table

Length (L) (mm)	Width (W) (mm)	Height (H) (mm)
190	90	90
190	90	40

Table 4.1 Size of Modular Bricks

The following non-modular sizes of the bricks may also be used

Length (L) (mm)	Width (W) (mm)	Height (H) (mm)
230	110	70
230	110	30

Table 4.2 Size of Non-Modular Bricks

Tolerances The dimensions of bricks when tested in accordance with 5.1.1 shall be within the following limits per 20 bricks:

For Modular Size

Ø  Length 3720 to 3880 mm (3800 ± 80 mm)

Ø  Width 1760 to 1840 mm (1800 ± 40 mm)

Ø  Height 1760 to 1840 mm (1800 ± 40 mm) (For 90 mm high bricks)

o   760 to 840 mm (800 ± 40 mm) (For 40 mm high bricks)

For Non-modular Size

Ø  Length 4520 to 4680 mm (4600 ± 80mm)

Ø  Width 2160 to 2240 mm (2200 ± 40mm)

Ø  Height 1360 to 1440 mm (1400 ± 40mm) (For 70 mm high bricks)

o   560 to 640 mm (600 ± 40mm) (For 30 mm high bricks)

4.2.3 CLASSIFICATION

The fly ash-lime bricks shall be classified on the basis of average wet compressive strength as given in Table.

Class Designation	Average compressive strength
	Not Less Than N/mm2	Less Than N/mm2
350	35	40
300	30	35
250	25	30
200	20	25
175	17.5	20
150	15	17.5
125	12.5	15
100	10	12.5
75	7.5	10
50	5	7.5
35	3.5	5

Table 4.3 Classification of Bricks Class Designation

4.3 PHYSICAL CHARACTERISTICS

4.3.1 COMPRESSIVE STRENGTH

The minimum average wet compressive strength of fly ash-lime bricks shall not be less than the one specified for each class. When tested as described in IS 3495 (Part 1). The wet compressive strength of any individual brick shall not fall below the minimum average wet compressive strength specified for the corresponding class of bricks by more than 20 percent.

4.3.2 WATER ABSORPTION

The bricks, when tested in accordance with the procedure laid down in IS 3495 (Part2), after immersion in cold water for 24 hrs. Shall have average water absorption not more than 20 percent by mass up to class 12.5 and 15 percent by mass for higher classes.

4.3.3 EFFLORESCENCE TEST

The bricks when tested in accordance with the procedure laid down in IS 3495 (Part 3 ), shall have the rating of efflorescence not more than ‘moderate’ up to Class 12.5 and ‘slight’ for higher classes.

4.4 RAW MATERIALS

The raw material that is used for Cement ash bricks are

4.4.1 CEMENT

A cement is a binder, a substance that sets and hardens and can bind other materials together. Cement used in the experimental work is Ramco Ordinary Portland Cement 43 grade conforming to IS 8112 (1989).

Specific gravity of cement = 3.1

Fig 4.1 Ordinary Portland Cement 43 Grade

4.4.2 QUARRY DUST

Quarry dust was purchased which satisfied the required properties of fine aggregate required for experimental work and the sand conforms to zone III as per the specifications of IS383:1970. Particles passing through 4.75mm sieve.

Specific gravity of Quarry Dust = 2.6

4.4.3 RICE HUSK ASH

Rice husk ash is obtained by burning rice husk. Physical properties of RHA are greatly affected by burning conditions. When the combustion is incomplete, large amount of unburnt carbon is found in the ash. When combustion is completed, grey to whitish ash is obtained. The amorphous content depends on burning temperature and holding time. Optimum properties can be obtained when rice husks are burnt at 500 - 700° C and held for short time, this temperature at which the husk is being burnt is less than that required for formation of clinkers in cement manufacturing process, the resulting ash can be used as a replacement of Quarry dust in Bricks.

Specific gravity of Rice Husk Ash = 2.2

Fig 4.3 Rice Husk Ash

4.4.4 SUGARCANE BAGASSE ASH

The burning of bagasse which a waste of sugarcane produces bagasse ash. Presently in sugar factories bagasse is burnt as a fuel so as to run their boilers. This bagasse ash is generally spread over farms and dump in ash pond which causes environmental problems also research states that Workplace exposure to dusts from the processing of bagasse can cause the chronic lung condition pulmonary fibrosis, more specifically referred to as bagassosis. So there is great need for its reuse, also it is found that bagasse ash is high in silica and is found to have pozzolanic property so it can be used as substitute to construction material.

Specific gravity of Sugarcane Bagasse Ash = 2.4

4.4.5 CHICKEN FEATHERS ASH

            The chicken feathers ash is obtained from burning chicken feathers. These Chicken feathers are spread over waste land and forms solid waste management problems. So in that case the chicken feathers are buried and the resulting ash can be used as a replacement of Quarry dust in Bricks.

Specific gravity of Chicken Feathers Ash = 2.1

4.5 PROCUREMENT OF RAW MATERIALS

4.5.1 CEMENT

            Cement used in this project is Ramco 43 Grade from Thirumayam, Pudukkottai Dist, Tamilnadu.

4.5.2 QUARRY DUST

            Quarry Dust used in this project is from Lena Vilaku, Pudukkottai, Tamilnadu.

4.5.3 RICE HUSK ASH

            Rice husk ash from Rice Mill at Pallathur, Sivagangai Dist, Tamilnadu.

4.5.4 SUGARCANE BAGASSE ASH

            Sugarcane bagasse from Juice centre at Karaikudi, Sivagangai Dist, Tamilnadu.

4.5.5 CHICKEN FEATHERS ASH

            Chicken feathers from Broiler chicken centre at Tirumayam, Pudukkottai Dist, Tamilnadu

4.5.6 WATER

            Water used in this project is from Department of Civil Engineering, MZCET, Pudukkottai.

4.6 MANUFACTURING PROCESS

4.6.1 PROPORTIONING

Rice Husk Ash, Sugarcane Bagasse Ash, Chicken Feathers Ash, Cement and Quarry dust 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 tabulated below

SAMPLE	RHA	SCBA	CFA	TOTAL ASH	QUARRY DUST
M	36%	14%	5%	55%	45%
N	39%	12%	6%	57%	43%
P	43%	10%	7%	60%	40%

Table 4.4 Mix Proportion

4.6.2 WEIGHING

The quantities of Rice Husk Ash, Sugarcane Bagasse Ash, Chicken Feathers Ash, cement, Quarry dust, and water for each batch shall be determined by weight, to an accuracy of 0.1 percent of the total weight of the batch.

4.6.3 MIXING

The materials are mixed by means of hand mixing.

4.6.4 CONVEY TO MOULD AND COMPACTION

The homogenised mixed material is put into the mould boxes. The product is compacted under vibration / hydraulic compression etc.

4.6.5 DEMOULDING

            The mould is removed from the Bricks within 3 to 5 seconds.

4.6.6 CURING PROCESS DRY AND WET

The green bricks are dried up under sun from 24 to 48 hours the dried up bricks are stacked and subjected for water spray curing once or twice a day, for 7-21 days, depending on ambience.                             

4.6.7 BRICKS ARE READY TO DISPATCH

The bricks are tested and sorted before dispatch.

Fig 4.12 Bricks are ready to Dispatch

4.7 POLLUTION CONTROL NEEDS

Workmen working with Rice Husk Ash, Sugarcane Bagasse Ash and Chicken Feathers Ash and at the mixing area are to be provided with protective equipment like dust masks and safety goggles.

4.8 ADVANTAGES

Ø  Energy Efficient

Ø  Structurally sound

Ø  Strong

Ø  Durable

Ø  Versatile

Ø  Safe

Ø  Secure

Ø  Robust

Ø  Economical

Ø  Will not Warp, Twist or Rot

Ø  100% Recyclable- Huge saving in foundation and structure savings up to 30% on beam costs.

Ø  Easy handling.

Ø  Faster construction.

Ø  Non toxic fumes in case of fire.

Ø  Highly accurate and smooth walls reduction in plastering.

Ø  It is eco-friendly.

Ø  Full size and shape saving cement in mortar and plaster.

Ø  Less wastage and breakages

Ø  Efflorescence and Vermin free

Ø  Reduce dead load on total Building Structure, thus saving steel and cement High strength and light weight.

Ø  It can reduce 10% of water consumption.

Ø  Due to high strength, practically no breakage during transport and use.

Ø  These bricks do not require longer soaking in water, only sprinkling of water before use is enough

Ø  Compressive strength is more than conventional clay bricks

Ø  More resistant to salinity and water than conventional bricks

Ø  Uniform in shape & size and more durable as strength increases with passage of time

Ø  Less mortar consumption in masonry & saving in plastering cost.

Ø  Comparatively less quantity of cement mortar by 20%-25% is required.

Ø  Water absorption is 10% to 11% as compared to 20% for conventional bricks.

Ø  Outside wall plastering could be avoided as these bricks are smooth.