hybrid bricks

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HYBRID BRICKS DONE BY M.AHAMED MOHAMED VAJEER (9489539488), N.S.MOHAN KUMAR (7845521268), CIVIL IV YR, THANTHAI PERIYAR GOVT. INSTITUTE OF TECHNOLOGY.

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Page 1: Hybrid Bricks

HYBRID BRICKS

DONE BY

M.AHAMED MOHAMED VAJEER (9489539488),N.S.MOHAN KUMAR (7845521268),

CIVIL IV YR,THANTHAI PERIYAR GOVT. INSTITUTE OF TECHNOLOGY.

VELLORE-02.

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Abstract Building materials industry plays a vital role in our national a natural building material has been used since ages and the trend was changed to man-made building units called as bricks. Various traditional construction materials exist which have proved to be suitable for a wide range of buildings and which have a great potential for increased use in the future. One such material is the compressed stablised earth block an improved from of one of the oldest material used in building construction. Soil is one of the primary materials used for construction of traditional low-cost bricks and is well suited to local weather conditions and occupancy patterns. Compressed earth blocks can also be used for almost all the applications of burnt clay bricks. Compressed stabilized earth bricks can be used for load bearing construction up to ‘3 stories’. In this study an attempt was made to study the characteristics of CSE bricks with respect to the varying cement and water content. The main composition of earth bricks is red soil or laterite soil which is collected from the nearby site, thereby reducing transportation cost. Cement was used as a stabilizer and sand of zone-1 gradation was used as a filler material. In this experimental investigation, the soil was tested as per IS codal procedure and the properties are presented. The bricks are made with varying cement and water content and these results are also presented. It is studied from the various laboratory tests conducted on these brick, it can replaced effectively in terms of conventional bricks irrespective of their uses. The compressive strength of nearly 5MPa just for cement content of 7% was achieved on 28 days moist curing which is stacked on open air. More there is no burning process involved in these bricks, there is much savings in the cost of fuel as well as in the overall cost of these bricks.

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INTRODUCTION

GENERAL

The building materials industry plays a vital role in our national economy. Stone, a

natural building material has been used since ages and the trend was changed to mane-made

building units called as bricks. Various traditional construction materials exist which have

proved to be suitable for a wide range of buildings and which have a great potential for

increased use in the future. One such material is the compressed stabilized earth block an

improved form of one of the oldest material used in building construction.

Fired bricks have potential of 460 billion bricks every year, which has been proven by

NCAER and leading brick association and is increasing steadily by 3-5% growth rate every

year. Even 5% market share will lead to 23 million bricks per year. Soil is one of the primary

materials used for construction of traditional low-cost bricks and is well suited to local weather

conditions and occupancy patterns. Compressed earth blocks can be used for almost all the

applications of burnt clay bricks. SCEBs can be used for load bearing construction up to 3

stories.

Soil construction methods are used in 80% of urban buildings. While this figure exceeds

90% in rural areas. Buildings are constructed entirely, or partially of soil, depending on

location, climate, available skills, cost, building use and local tradition.

Compressed earth bricks are building blocks formed from stabilized or un-stabilized

compressed earth. When a brick is compressed it loses 30% of its volume. This is due to the

mechanical compression of the press driving out air pockets and aligning wet clay particles and

compacting the clay around the sand particles. There are many stabilizers that can be used.

They can be broadly classed into natural and manufactured. They include such wondrous things

as plant juices, whey, resins, molasses, wood ashes, and lime just to name a very few. Here the

presence and low cost of cement makes it both physically and economically efficient. Some

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sources don't even recommend using stabilizers other than cement even when building in

developing countries.

SCOPE OF PRESENT STUDY

There has been a consistent effort to promote the use of compressed earth block as

building units instead of burnt bricks. Earlier attempts reveals that the stabilized compressed

earth bricks posses sufficient properties which can be used in place of burnt bricks, which has

an acute shortage. (Auroville Earth Institute Report)

Hence, in the present study an attempt was made to incorporate stabilized earth brick in

place of conventional fired bricks and to understand the behavior of stabilized earth brick with

respect to cement content.

FORMAT OF PRESENTATION

A comprehensive comparative review on the manufacturing process and characteristics

of conventional burnt bricks and stabilized earth bricks was made and it is given in chapter 2.

Experimental investigation to make the comparative studies on compressive strength of

stabilized earth bricks with respect to percentage of stabilizer used are given in chapter 3.

Results and discussion based on the above investigation and conclusion are given in chapter 4

and chapter 5.

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LITERATURE REVIEW

GENERAL

In this chapter, the materials used to make Compressed stabilized Earth Bricks,

stabilizers and Additives used, manufacturing and curing process are briefly presented.

MATERIALS FOR CSEB

The sole ingredients of CSEB were Red sand or laterite soil. These soils are formed

from the breakdown of the Sandstone rock that underlies soils. This soil type also occupies large

expanses of land area in India. In general, however, knowledge of the engineering properties of

these soils is limited. They are mainly red or brown ironstone soils formed in dry arid

conditions. Attempts have been made to relate them to the laterite and lateritic soils, but they

possess different properties to those soils. Soils include windblown sands, silt and clays that

have accumulated in depths of up to 5m, where the lower layers have become consolidated with

time. Many villagers in these areas have built dwellings from soils that demonstrate greater

durability properties than those buildings made from soils.

A possible reason for this is that soils tend to have a lower clay content so they expand

and shrink less on wetting and drying, making them more stable through periods of climatic

fluctuation. Soil characteristics and climatic conditions of an area must be evaluated before

manufacturing soil building blocks. A dry climate, for example, needs different soil blocks from

those used in temperate, rainy or tropical areas. All soils are not suitable for every building

need.

The basic material, however, required to manufacture compressed stabilised earth

building blocks is a soil containing a minimum quantity of silt and clay so as to facilitate

cohesion. Soils are variable and complex materials, whose properties can be modified to

improve performance in building construction by the addition of various stabilisers. All soils

consist of disintegrated rock, decomposed organic matter and soluble mineral salts. Soil types

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are graded according to particle size using a system of classification widely used in civil

engineering. This classification system based on soil fractions shows that there are 4 principal

soil fractions - gravel, sand, silt and clay.

For soil stabilisation, the clay fraction is most important because of its ability to provide

cohesion within a soil. The manufacture of good quality, durable compressed stablised earth

blocks requires the use of soil containing fine gravel and sand for the body of the block,

together with silt and clay to bind the sand particles together. An appropriate type of stabiliser

must be added to decrease the linear expansion that takes place when water is added to the soil

sample. The stabiliser has further benefits that are described in a later section.

Name of fraction Diameter size ranges of particles (mm)

Gravel

Coarse gravel 20.00-60.00

Medium gravel 6.00-20.00

Fine gravel 2.00-6.00

Sand

Coarse sand 0.600-2.000

Medium sand 0.200-0.600

Fine sand 0.060-0.200

Silt

Coarse silt 0.020-0.060

Medium silt 0.006-0.020

Fine silt 0.002-0.006

Clay Clay Less than 0.002

STABILIZER

Silt and clay within a soil sample react to moisture, swelling when water is absorbed,

and shrinking when the soil dries out. Such movement can result in surface cracking of walls

and consequently accelerate erosion, which may eventually lead to structural failures.

Movement often causes the crumbling of surface coatings. The main objective of soil

stabilisation is to enhance soil resistance to the erosive effects of the local weather conditions,

including variations in temperature, humidity and rainwater. The use and adoption of the right

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stabilisation method can improve the compressive strength of a soil by as much as 400 to 500%

and increase its resistance to erosion and mechanical damage.

Good resistance to erosion can be obtained in one or more of the following ways:

increasing the density of the soil,

adding a stabilising agent that either reacts with, or binds the soil grains

together,

Adding a stabilising agent which acts as a waterproofing medium.

Ordinary Portland cement hydrates when water is added, the reaction produces a

cementitious gel that is independent of the soil. This gel is made up of calcium silicate hydrates,

calcium aluminate hydrates and hydrated lime. The first two compounds form the main bulk of

the cementitious gel, whereas the lime is deposited as a separate crystalline solid phase. The

cementation process results in deposition between the soil particles of an insoluble binder

capable of embedding soil particles in a matrix of cementitious gel. Penetration of the gel

throughout the soil hydration process is dependent on time, temperature and cement type. The

lime released during hydration of the cement reacts further with the clay fraction forming

additional cementitious bonds. Soil-cement mixes should be compacted immediately after

mixing in order not to break down the newly created gel and therefore reduce strengthening.

The basic function of cementation is to make the soil water-resistant by reducing swelling and

increasing its compressive strength.

With respect to the general processes of cementation, penetration and binding mentioned

above, many factors must be considered. Processes may also vary between different types of

soils. Cement is considered a good stabiliser for granular soils but unsatisfactory for clays.

Generally cement can be used with any soil type, but with clays it is uneconomical because

more cement is required. The range of cement content needed for good stabilisation is between

3% and 18% by weight according to soil type.

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Findings have shown that there is a relationship between linear shrinkage and cement

content need for stabilisation. Table 2.3 shows that the cement to soil ratio ranges between

5.56% and 8.33% for measured shrinkage variations of between 15mm to 60mm.

Measured shrinkage Cement to soil ratio

Under 15 1:18 parts (5.56%)

15-30 1:16 parts (6.25%)

30-45 1.14 parts (7.14%)

45-60 1:12 parts (8.33%)

It may be noted that for a given shrinkage the cement to soil ratio is function of the

compaction effort exerted. Over this shrinkage value, 6% to 8% cement would need to be used

for effective stabilization.

ADDITIVE

An additive is a substance added during manufacture, intended to improve the final

characteristics of the CSEB or to enhance particular characteristics. The most common additives

are stabilisation products, know as stabilisers, such as cement, lime, pozzolonas, etc. intended to

neutralise the sensitivity to water of the fine fraction and thus to maintain cohesion at an

acceptable level even in a humid state. But other additives can also be used to modify other

characteristics such as colour (colouring agents), tensile strength and reducing shrinkage cracks

(fibres), etc.

PRODUCTION PROCESS

The production of SCEB is based on the principle of densification of raw earth mixed

with stabilizer (cement or lime) in small quantities ranging from 5-10% by weight of the mix.

The production process incorporates 3 main stages

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1. Mix Preparation

2. Compaction

3. Post Production

Mix Preparation Compaction Post Production

a. Sieving

b. Batching

c. Mixing

a. Filling the mould

b. Moulding

c. Block ejection and

stacking

a. Moisture curing

b. storage

CURING

To achieve maximum strength, compressed stabilised earth blocks need a period of

damp curing, where they are kept moist. This is a common requirement for all cementations

materials. What is important is that the moisture of the soil mix is retained within the body of

the block for a few days. If the block is left exposed to hot dry weather conditions, the surface

material will lose its moisture and the clay particles tend to shrink. This will cause surface

cracks on the block faces. In practice, various methods are used to ensure proper curing. Such

methods include the use of plastic bags, grass, leaves, etc. to prevent moisture from escaping.

After two or three days, depending, on the local temperatures, cement stabilized blocks

complete their primary cure. As the stack of blocks is built up, the top layer should always be

wetted and covered, and the lower layer should be allowed to air-dry to achieve maximum

strength.

Alternatively, freshly moulded blocks can be laid out in a single layer, on a non-

absorbent surface, and covered with a sheet to prevent loss of moisture. The required duration

of curing varies from soil to soil and, more significantly, which type of stabiliser is used. With

cement stabilisation, it is recommended to cure blocks for a minimum of three weeks. The

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curing period for lime stabilisation should be at least four weeks. Compressed stabilised earth

blocks should be fully cured and dry before being used for construction.

PROPERTIES OF COMPRESSED EARTH BLOCKS

COMPRESSIVE STRENGTH

The compressive strength of compressed stabilised earth building blocks depends upon

the soil type, type and amount of stabiliser, and the compaction pressure used to form the block.

Maximum strengths are obtained by proper mixing of suitable materials and proper

compacting and curing. In practice, typical wet compressive strengths for compressed stabilised

earth building blocks may be less than 4MN/m2.

DENSITY AND THERMAL PROPERTIES

Normally compressed stabilised earth blocks are denser than a number of concrete

masonry products such as burnt bricks, aerated and lightweight concrete blocks. While having

densities within the range of various types of bricks e.g. clay, calcium silicate and concrete

bricks.

The high density of compressed stabilised earth blocks may be considered as a

disadvantage when the blocks have to be transported over long distances. However, it is of little

consequence when they are produced at or near the construction site. Low density compressed

stabilised earth blocks have an advantage over high density ones of acting as better thermal

insulators. This is particularly advantageous in hot dry climates where extreme temperatures can

be moderated inside buildings made of compressed stabilised earth blocks.

MOISTURE MOVEMENT

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Building materials with high porosity when used for wall construction may expand

slightly in wet and dry conditions. Such movements may result in cracking and other defects to

the building. Expansion of compressed stabilised earth blocks may vary according to the

properties of the soil; some soils expand or shrink more than others. The addition of a stabiliser

will reduce this expansion. In general, however, there may be greater movement in structures

built with compressed stabilised earth blocks than those using alternative construction materials.

Proper block manufacture and construction methods, however, will reduce such movement.

Moisture movement is denoted in terms of linear per cent change. It is worth mentioning that

moisture movement becomes especially important when two materials with different movement

properties are used in a building. Differential movement results in stress which may break the

bond between the materials, or cause other damage. For example, cement renderings often peal

off earth walls or poorly compressed stabilised earth blocks because of their different expansion

properties.

DURABILITY, MAINTENANCE AND APPEARANCE

As a rule soil blocks containing stabilisers show greater resistance to extreme weather

conditions. Block making experiments in Sudan using various quantities of lime as a stabiliser

showed marked variations between the durability of stabilised and un-stabilised compressed

earth blocks. Compressed stabilised earth blocks demonstrated good weathering properties.

Blocks of the same size, when made of a sufficiently good quality and shape with a high

quality finish, can be used for fair-faced walling. Their appearance depends upon soil colours,

particle size, and degree of compaction used. With good high quality blocks external or even

internal rendering should not be necessary.

A white wash finish applied directly to the blocks as a render coat could be used to

reduce solar gain. It should be noted that compressed stabilised earth blocks, in common with

other types of blocks and bricks, will need adequate steel reinforcement if used in areas prone to

earthquakes or cyclones etc. Termites, bacteria, fungi and fire do not present a particular hazard

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for compressed stabilised earth blocks. However, organic material in the soil may weaken the

strength of the block.

STANDARDS FOR BLOCK PRODUCTION

Many aspects should be taken into consideration before launching an operation to

produce compressed stabilised earth building blocks:

amount and type of stabiliser required,

soil properties and its suitability for stabilisation,

building standards and hence quality of blocks required,

load bearing requirements of construction i.e. single storey or more.

The final wet compressive strength of a compressed earth block depends not only on soil

type, but also on the type and amount of stabiliser, the moulding pressure, and the curing

conditions.

EXPERIMENTAL INVESTIGATION

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GENERAL

In this chapter the materials used for the production of CSEB was tested and the

experimental investigation on CSEB with respect to varying cement content are briefly

presented. The soil was collected within the college campus of Thanthai Periyar Government

Institute of Technology, vellore for this study.

SOIL TESTING

Laboratory analysis of the raw material is always necessary for large-scale production of

compressed stabilized earth blocks. For small-scale production, however, it is not essential to

employ sophisticated tests to establish the suitability

of a soil. Simple field tests can be performed to get an indication of the composition of the soil

sample. Such tests are discussed briefly below.

SPECIFIC GRAVITY TEST

The specific gravity of soil solids is determined by: (i) a 50 ml density bottle, or (ii) a

500 ml flask, or (iii) a pycnometer. The density bottle method is most accurate, and is suitable

for all types of soils. The flask or pycnometer is used only for coarse grained soils. The density

bottle method is the standard method used in the laboratory.

However, in all the three methods, the sequence of observations is the same. The mass

M1 of the empty, dry, bottle (r flask or pycnometer) is first taken. A sample of oven-dried soil,

cooled in desiccators, is put in the bottle, and the mass M2 is taken. The bottle is then filled with

distilled water (or kerosene) gradually, removing the entrapped air either by applying vaccum or

by shaking the bottle. The mass M3 of the bottle, soil and water (full up to the top) is taken.

Finally, the bottle is emptied completely and thoroughly washed and clean water (or kerosene)

is filled to the top, and the mass M4 is taken. Based on these four observations, the specific

gravity can be computed.

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SIEVE ANALYSIS

The complete sieve analysis can be divided into two parts – the coarse analysis and fine

analysis. An oven dried sample of soil is separated into two fractions by sieving it through a

4.75 mm IS sieve. The portion retained on it is termed as the gravel fraction and is kept for the

coarse analysis, while the portion passing through it (-4.75 mm size) is subjected to fine

analysis. The following set of sieves are used for coarse sieve analysis: IS: 100,63, 20, 10 and

4.75 mm. the sieves used for fine analysis are: 2 mm, 1.0 mm, 600, 425, 300, 212, 150 and75

micron IS sieves.

Sieving is performed by arranging the various sieves sizes one over the other in the

order of their mesh openings. The largest aperture sieve being kept at the top and the smallest

aperture sieve at the bottom. A receiver is kept at the bottom and a cover is kept at the top of the

whole assembly. The soil sample is put on the top sieve, and whole assembly is fitted on a sieve

shaking machine.

The amount of shaking depends upon the shape and the number of particles. At least 10

minutes of shaking is desirable for soils with small particles. The portion of the soil sample

retained on each sieve is weighed. The percentage of soil retained on each sieve calculated on

the basis of the total mass of soil sample taken and from these results, percentage passing

through each sieve is calculated.

It is advisable to wash the soil portion passing through 4.75 mm sieve over 75 micron

sieve so that sit and clay particles sticking to the sand particles may be dislodged. Two grams of

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Sl.No Determination Trial I Trial II

1. Weight of empty pycnometer w1(g)

490 g 490 g

2. Weight of pycnometer + soil w2 (g)

805 g 800 g

3. Weight o f pycnometer + soil + water w3 (g)

1455 g 1450 g

4. Weight of pycnometer + water w4 (g)

1260 g 1260 g

5. Specific gravity of soil sample 2.65 2.64

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sodium hexametaphosphate is added per liter of eater used. Washing should be continued until

the after passing through 75 micron sieve is substantially clean.

The fraction retained on the 75 micron sieve is dried in the oven. The dried portion is

then re-sieved through 2 mm, 1 mm, 600, 425, 300, 212, 150 and 75 micron IS sieves. The

portion passing 75 micron sieve (while washing) is also dried separately and its mass

determined to get % finer than75 micron size. If the portion passing 75 micron size is

substantial, wet analysis is done for further sub-division of particle size distribution.

In this investigation, the soil was washed through 75micron sieve and the soil portion

retained is then dried and again dry sieve analysis is carried out. The sieve analysis is presented

in the figure 3.1.

Table: Sieve analysis of red soil

Sieve Size Weight Retained

% Weight Retained

Cummulative % Retained

% Finer

10 0 0.00 0.00 100.0

4.75 28.6 2.86 2.86 97.1

2.36 201.9 20.19 23.05 77.0

1.18 218.26 21.83 44.88 55.1

0.6 175.44 17.54 62.42 37.6

0.425 93.22 9.32 71.74 28.3

0.3 68.46 6.85 78.59 21.4

0.15 79.64 7.96 86.55 13.4

0.075 33.4 3.34 89.89 10.1

pan 101.08 10.11 100.00 0.0

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D10 0.075 Cu 20.00 % Gravel 2.9D30 0.38     %Coarse sand 27.1D60 1.5 Cc 1.28 %Medium sand 41.7

%Fine sand 18.2%Clay & Silt 10.1

Figure .Gradation Analysis on red soil

0.001 0.01 0.1 1 100.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0100.097.1

77.0

55.1

37.6

28.3

21.4

13.410.1

Particle Size (mm)

% F

iner

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STANDARD PROCTOR TEST

Standard proctor test was performed in order to estimate the value of maximum dry

density and optimum moisture content. The maximum dry density of 1.94 g/cc was obtained at

moisture content of 10.5% and it is presented in figure 3.2.

Table: Standard proctor compaction test

No of Trials 1 2 3 4 5

Wt. of soil + mould 6475 6570 6635 6615 6500Wt. of soil 2035 2130 2195 2175 2060water content 6 8 10 12 14Vol of water 150 200 250 300 350actual Vol water 164.76 214.76 264.76 314.76 364.76Act water content 6.59 8.59 10.59 12.59 14.59Bulk density 2.04 2.13 2.20 2.18 2.06dry density 1.92 1.97 2.00 1.94 1.81Atcual Dry density 1.91 1.96 1.98 1.93 1.80

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5.00 7.00 9.00 11.00 13.00 15.00 17.00 19.001.70

1.75

1.80

1.85

1.90

1.95

2.00

2.05

2.10

2.15

2.20

Water Content %

Dry

Dens

ity g

/cc

Figure 3.2 Plot of Maximum dry density Verses Optimum moisture content

CSEB MIXTURES

Six mixtures have been considered in this work with varying cement content and the details are presented in Table 3.3

Sl. No.

Cement content

Weight of cement in g

Weight of Sand in g

Weight of soil in g

Mix designation

1 3% 167 1113 4286 C320B2 4% 223 1113 4230 C420 B3 5% 279 1113 4174 C520 B4 6% 334 1113 4119 C620 B5 7% 390 1113 4067 C720 B6 8% 446 1113 4007 C820 B

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PREPARATION OF SPECIMENS

CSEB was prepared using steel mould of size (230 x110x100)mm by giving a standing

load of 40kN uniformly for all mixtures. The freshly prepared earth bricks were kept on the

floor for one day and then stacked in the open yard and cured by spraying water on it for 28

days. After 28 days the earth brick specimens were tested for its compressive strength.

TESTS ON EARTH BRICKS

The compressed stabilized earth brick is subjected to the following tests to find out its suitability for the construction work:

1. Water absorption test2. Crushing strength test

WATER ABSORPTION TEST

A brick is taken and it is weighed dry. It is then immersed in water for a period of 24

hours. It is weighed again and the difference in weight indicates the amount of water absorbed

by the brick. As per IS 3495:1976, it should not, in any case, exceed 20 percent of weight of dry

brick.

CRUSHING STRENGTH TEST

The crushing strength of a brick is found out by placing it in a compression testing

machine. It is pressed till it breaks. As per IS: 1077-1976 the minimum crushing or compressive

strength of bricks is 3.50 N/mm2. The bricks with crushing strength of 7 to 14N/mm2 are graded

as A and those having above 14 N/mm2 are graded as AA.

The results are tabulated and presented in the next chapter.

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RESULTS AND DISCUSSIONS

GENERAL

The results of the various tests conducted on the CSEB with different cement content are presented in this chapter.

RESULTS AND DISCUSSIONS

WATER ABSORPTION TEST

The water absorption of CSEB Mix of C720B was found to have a low water absorption of 8.4% which may be due to higher density and may due to low porosity. (Refer table 4.1). The variation of water absorption with respect to various cement content was also presented in figure 4.1

Table: Water absorption of CSE Bricks

Sl. No.

Mix Designation

Average Water absorption

1 C320B 10.952 C420B 10.833 C520B 10.404 C620B 8.635 C720B 8.406 C820B 10.46

3% 4% 5% 6% 7% 8%0

2

4

6

8

10

12

WATER ABSORPTION OF EARTH BRICKS

% of cement

avg

wat

er a

bsor

ptio

n va

lue

(%)

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Table Figure shows variation of Water absorption Vs percent cement content

CRUSHING STRENGTH TEST

The crushing strength of CSE bricks of Mix C720B was found to have a higher value of

5.22MPa than CSE bricks of other mixes. This is validated from the low water absorption of

that particular mix and hence higher density. Moreover, the CSE bricks at low cement content

having low strength does not match with the codal specification as per IS: 1077-1976 and its

presented in table 4.2 and in figure 4.2.

Table: Compressive Strength of CSE Bricks

Sl. No.

Mix Designation

Average Compressive

Strength MPa1 C320B 1.022 C420B 2.183 C520B 3.354 C620B 4.895 C720B 5.226 C820B 4.28

3% 4% 5% 6% 7% 8%0

1

2

3

4

5

6

COMPRESSIVE STRENGTH OF EARTH BRICKS

% of cement

avg

com

pres

sive

str

engt

h (N

/mm

2)

Table Figure shows variation of Water absorption Vs percent cement content

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CONCLUSIONS

GENERAL

Based on experimental investigations carried out on Compressed Stabilised Earth Bricks of various cement content the following conclusion are identified and presented.

1. The Cured CSE Bricks is found to have high water absorption at low cement content

and decreases as the cement content increases.

2. The compressive strength of CSE Bricks increases as cement content increases and the compressive strength value decreases for higher cement content. This is because of low porosity by which the cement particle does not have enough water pore space to hydrate and hence low strength. Further, it needs detailed investigation to be done in this area.

3. It is further ensured that the SCE Bricks was found to be useful in place of fired bricks.

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REFERENCES

1. Soil mechanics and foundations by Dr. B.C.Punmia, Ashok Kumar Jain, Arun Kumar Jain

– Laxmi publication (P) Ltd.

2. Indian standard code IS 456 : 2000 and IS 875 (Part 1)-1987

3. National Building code - 2005.

4. IS 460:1962 Methods of Test for Soils - Grain Size Analysis

5. IS 2720 : Part III : Sec 2 : 1980 Test for Soils - Part III : Determination of Specific Gravity -

Section 2 : Fine, Medium and Coarse Grained Soils

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