Study On Effect Of Chemical Stabilizing Agents On … Engineering College, Rampachodavaram, A.P,...

480 Mallika, B. Ganesh

International Journal of Engineering Technology Science and Research

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Study On Effect Of Chemical Stabilizing Agents On Strength

And Swelling Properties Of Soils

Mallika1, B. Ganesh2 1M.Tech student (14961D87 ), Lenora Engineering college, Rampachodavaram, A.P, India

2Assistant Professor, Department of Civil Engineering,

Lenora Engineering College, Rampachodavaram, A.P, India

ABSTRACT

In India, expansive soils popularly known as black cotton soils are highly problematic, as they swell on absorption of

water and shrink on evaporation thereof. Because of this alternate swell and shrinkage, distress is caused to the

foundations of structures laid on such soils. Understanding the behavior of expansive soil and adopting the appropriate

control measures have been great task for the geotechnical engineers. Proper characterization and selection of suitable

foundation is essential in case of problematic soils. Extensive research is going on to find the solutions to black cotton

soils. There have been many methods available to control the expansive nature of the soils. Treating the expansive soil

with electrolytes are one of the technique to improve the behavior of the expansive ground. Hence, in the present work,

experimentation is carried-out to investigate the influence of electrolytes like calcium chloride and ferric chloride on the

properties of expansive soil. A methodical process, involving experimentation in the laboratory under controlled

conditions is done. With addition of electrolytes to the expansive soil, improvement in its physical and engineering

properties is observed. It is observed that the maximum improvement in properties of expansive soil is obtained for

Ferric Chloride treatment compared to other electrolytes tried in this investigation

Key words: Calcium chloride and ferric chloride Electrolytes, black cotton soil, Ferric Chloride.

1. INTRODUCTION

Expansive soil is one among the problematic soils that has a high potential for shrinking or swelling due to

change of moisture content. Expansive soils can be found on almost all the continents on the Earth.

Destructive results caused by these soils have been reported in many countries. In India, large tracts are

covered by expansive soils known as black cotton soils. The major area of their occurrence is the south

Vindhyachal range covering almost the entire Deccan Plateau. These soils cover an area of about 200,000

square miles and thus form about 20% of the total area of India. To a large extent they are found in regions

having low to medium slope and poor drainage conditions. The primary bed rock is basalt or trap and in some

locations quartizites, schists and sedimentary rocks are found. It is expensive in nature due to the presence of

montmorillonite and illite clay minerals. Some of these black cotton soils are also found to contain high

amount of carbonates. The depth of black cotton soils can be as high as 20m.

The primary problem that arises with regard to expansive soils is that deformations are significantly greater

than the elastic deformations and they cannot be predicted by the classical elastic or plastic theory. Movement

is usually in an uneven pattern and of such a magnitude to cause extensive damage to the structures resting on

them.

Proper remedial measures are to be adopted to modify the soil or to reduce its detrimental effects if expansive

soils are indentified in a project. The remedial measures can be different for planning and designing stages

and post construction stages. Many stabilization techniques are in practice for improving the expansive soils

in which the characteristics of the soils are altered or the problematic soils are removed and replaced which

can be used alone or in conjunction with specific design alternatives. Additives such as lime, cement, calcium

chloride, rice husk, fly ahs etc. are also used to alter the characteristics of the expansive soils. The effect of the

additives and the optimum amount of additives to be used are dependent mainly on the mineralogical



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composition of the soils. The project focuses about the various stabilization techniques that are in practice for

improving the expansive soil for reducing its swelling potential and the limitations of the method of

stabilization there on. Modification of BC soil by chemical admixture is a common method for stabilizing the

swell-shrink tendency of expansive soil.

2. LITERATURE REVIEW

Expansive soils pose the greatest hazards that many geotechnical engineers face. Such soils may cause heavy

damages in light loaded structures such as water canals, reservoirs, highways, railways and airport runways

etc., unless appropriate measures are taken. Various stabilization techniques are in practice for improving

expansive soils by reducing its swelling potential and increasing its strength characteristics. Modification of

expansive soil by chemical admixture is a common practice for stabilizing the swell shrink tendency of

expansive soil, Advantages of chemical stabilization are that they reduce the swell-shrink tendency of

expansive soils and also render the soils less plastic.

In this section, the experiences of various investigators concerning chemical stabilization using

calcium chloride have been reviewed. Numerous investigators have studied the influence of lime, cement,

lime-cement, lime-fly ash, and cement–fly ash mixes on soil properties, mostly focusing on the strength and

swelling aspects. Among the chemical stabilization methods for expansive soils, lime stabilization is mostly

adopted for improving the swell-shrink characteristics of expansive soils. As lime and cement are binding

materials, the strength of soil-additive mixtures increases provided the soil is reactive with them. However, for

large-scale field use, the problems of soil pulverization and mixing of additives with soil have been reported

by several investigators.

Calcium chloride is an inorganic salt, which is a by-product of sodium carbonates. The use of

calcium chloride in place of lime, as calcium chloride is more easily made into calcium charged supernatant

than lime. Recent study indicated that CaCl2 could be an effective alternative to conventional lime used due to

its ready dissolvability in water and to supply adequate calcium ions for exchange reactions.

Petry and Armstrong (1989) stated that the calcium ions are the most effective and abundantly available in

calcareous fly ash, lime and calcium chloride, further the authors mentioned that the reasons why calcium

chloride has not been widely used are not clear. It is believed that the main one is economics, but perhaps it is

also because little definitive research has been done to define or support its use. Calcium chloride is known to

be more easily made into calcium charged supernatant than lime an helps in ready cation exchange reactions.

(Ramana Murthy, 1998). Mitchell and Radd (1973) also felt that CaCl2 might be effective in soils with

expanding lattice clays. Though, it is claimed that the magnitude of leaching in highly expansive clays

(KuulaVaisanen et al, 1995) over cycles of wetting and drying could be controlled by using Na2SiO3 along

with CaCl2. Though several works have been reported covering various aspects of chemical stabilization of

expansive soils, the understanding on cyclic swell-shrink behavior of stabilized and unstabilized soils was not

clear.

Chen and Ma (1987) felt that shrinkage cannot be treated as an image reflection of swelling and over a great

portion of the world shrinkage problems pose more of a threat to structural damage than swelling problems

especially in expansive clays of illite mineralogy.

Driscoll (1983) reported that in Britain, problems associated with swelling clays are largely related to the

shrinkage caused by extraction of moisture through tree roots. It is more useful if the complete cyclic swelling

and shrinkage behavior is understood.

Abouleid (1985) observed that there is nearly no volume change for remoulded clay specimens after three or

four wetting and drying cycles. From this discussion, it is evident that one group of researchers felt that the

swelling ability of clay decrease after few cycles of drying and wetting and yet another group recorded

increase in volume change after cyclic wetting and drying.

Reddy et al (1981) reported that, the test tracks with Murom sub-base and lime-pozzalana sub-base are rated

as the best among the ten test tracks constructed on expansive soil sub-grade with different sub-base courses.



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Deshpande et al (1990) concluded that lime stabilized sub base has shown better performance compared to

untreated section in the test track laid on expansive soil subgrade. Many researchers attempted to stabilize the

expansive soils by using different electrolytes. Here we discuss some of the projects carried out on expansive

soils using different electrolytes all around the world.

P. Venkata Muthyalu, K. Ramu and G.V.R. Prasada Raju (JNTUK) studied the “The Performance of

Chemically Stabilized Expansive Soil.”In this project they stabilized the expansive soil using electrolytes like

Potassium Chloride (KCL), Calcium Chloride (CaCl2) and Ferric Chloride (FeCl3). Ahmed T. M. Farid and

Mohamed I. Wahdan (Saudi Arabia) studied the “Behavior of Expansive Soil Treated by using Different

Electrolyte Substances.” In this project they stabilized the expansive soil by using electrolytes like Potassium

Chloride (KCL), Calcium Chloride (CaCl2) Sodium Chloride (NaCl) and Ferric Chloride (FeCl3).

EI Sharif M. Abdulaziz, Yahya K. Taha, Mamdouh A. Kenawi and O. Kamel (Egypt) studied the “Treatment

of Expansive Soil with Chemical Additives.” In this project they stabilized the expansive soil by using

chemical additives like Addicrete P and Addicrete BV. In this project we are going to use the electrolytes like

Calcium Chloride (CaCl2) and Ferric Chloride (FeCl3) to stabilize the expansive soil.

3. EXPERIMENTAL INVESTIGATION

3.0. Scope of Work:

The experimental work consists of the following:

1. Specific Gravity of soil

2. Determination of soil index properties (Atterberg Limits)

Liquid limit by cassagrande’s apparatus

Plastic Limit

3. Determination of the maximum dry density (MDD) and the corresponding optimum moisture content

(OMC) of the soil by Proctor compaction test.

4. Determination of the shear strength by unconfined compressive strength test (UCS).

5. Determination of swelling pressure of the soil by consolidometer method.

3.1. Materials Used:

Soil sample location: Near Kakinada.

Chemicals: Calcium chloride, Ferric chloride.

3.2. Preparation of Soil Sample:

Following steps are carried out while mixing the chemicals viz., calcium chloride, ferric chloride to the soil.

All the soil samples are prepared by mixing Normal soil and the chemicals.

Percentage of chemicals in soil sample is given by the following equation.

Pb= Wb/ Ws

Wb = Weight of each chemical

Ws = Weight of soil sample

Pb= Percentage of each chemical

Different percentages of calcium chloride and ferric chloride for our study are 0.5%, 1.0%, 1.5%, 2.0%

respectively.

3.3. Experiments Performed

Specific Gravity of Soil, Differential Free Swell (DFS), Liquid Limit Test, Plastic Limit Test , Particle Size

Distribution , Proctor Compaction Test, Shear Strength a). Direct shear test b) Tri-axial Compression Test

c) Vane Shear Test d) Unconfined Compressive Strength (UCS) Test, Swell Test Using Consolidometer

TEST RESULTS

Laboratory Test Results on the samples



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Table 1 (Specific Gravity for Untreated soil sample)

Type of soil = Oven Dried Soil Passing Through IS SIEVE425µ

S.No OBSERVATIONS READINGS

1 Mass of Empty Pyconometer (M1) grams 618

2 Mass of Pyconometer + Dry soil (M2) grams 1020

3 Mass of Pyconometer + Soil + Water (M3) grams 1850

4 Mass of Pyconometer + Water (M4) grams 1597

5 Mass of Dry Soil (M2-M1) grams 402

6 Mass of Wet Soil (M3-M4) grams 253

7 Specific Gravity G=(M2-M1)/(M2- M1)-(M3-M4) 2.69

Table-2 Differential Free Swell (DFS)

Chemical Cacl2 Fecl3

0% 140 140

0.5% 80 60

1.0% 70 50

1.5% 60 50

2.0% 50 40

Effect of electrolytes on Index Properties of expansive soil

Table-3 Liquid Limit: For untreated soil sample

S.No Particulars Trail-1 Trail-2 Trail-3 Trail-4

1 Cup number 1 2 3 4

2 Number of blows 40 32 30 17

3 Weight of Cup (W1) 21.94 13.82 13.77 25.46

4 Cup+ Soil Weight (W2) 26.62 27.89 22.79 34.03

5 Cup + Oven Dry Soil (W3) 24.87 22.34 19.1 29.91

6 Weight of Water(Ww) =(W2-W3) 1.75 5.55 3.69 4.12

7 Weight of Oven Dry Soil(WS) =(W3-W1) 2.93 8.52 5.33 4.45

8 Water Content = (Ww/Ws)*100 59.73 65.14 69.23 92.58

Untreated Soil Sample Graph

(Graph-1)

Table-4 Soil sample treated with 0.5% Cacl2:

Sl.no Particulars Trail-1 Trail-2 Trail-3 Trail-4

1. Cup number 1 2 3 4



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2. Number of blows 38 29 20 12

3. Weight of Cup (W1) 8.50 13.91 13.78 8.39

4. Cup+ Soil Weight (W2) 23.32 29.85 32.40 15.06

5. Cup + Oven Dry Soil (W3) 17.19 23.17 24.43 12.04

6. Weight of Water (Ww) =(W2-W3) 6.13 6.68 7.97 3.02

7. Weight of Oven Dry Soil(WS) =(W3-W1) 8.69 9.26 10.65 3.65

8. Water Content = (Ww/Ws)*100 70.54 72.14 74.83 82.73

Treated Soil sample (Normal soil + 0.5% Cacl2)

(Graph-2)

Table-5 Treated Soil Sample (Normal Soil + 1.0% Cacl2)

S.No Particulars Trail-1 Trail-2 Trail-3 Trail-4



3. Weight of Cup (W1) 8.40 13.78 8.54 14.10

4. Cup+ Soil Weight (W2) 19.57 22.10 18.85 31.50


6. Weight of Water(Ww) =(W2-W3) 4.23 3.27 4.34 6.98



Treated Soil Sample (Normal Soil + 1.0% Cacl2)



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(Graph-3)

Table-6 Soil sample treated with 1.5% Cacl2




3. Weight of Cup (W1) 8.42 13.80 9.82 8.51

4. Cup+ Soil Weight (W2) 19.41 22.97 19.92 16.18





Treated Soil Sample (Normal Soil + 1.5% Cacl2)

(Graph-4)

Table-7 Soil sample treated with 2.0% Cacl2



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3. Weight of Cup (W1) 8.57 8.41 8.74 8.34

4. Cup+ Soil Weight (W2) 14.82 13.84 15.61 15.47


6. Weight of Water(Ww) = (W2-W3) 2.31 2.05 2.63 2.83



Treated Soil Sample (Normal soil + 2.0% Cacl2)

(Graph-5)

Table -8 Soil sample treated with 0.5% FeCl3:




3. Weight of Cup (W1) 26.26 24.04 21.95 8.65

4. Cup+ Soil Weight (W2) 33.26 29.45 28.98 15.33





Treated Soil Sample (Normal Soil + 0.5% Fecl3)



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(Graph-6)

Table- 9 Soil sample treated with 1.0% Fecl3




3. Weight of Cup (W1) 13.78 13.74 13.82 13.94

4. Cup+ Soil Weight (W2) 19.17 19.26 19.65 19.83





Treated Soil Sample ( Normal Soil + 1.0% Fecl3)

(Graph-7)

Table-10 Soil sample treated with 1.5% Fecl3



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3. Weight of Cup (W1) 13.40 13.78 13.73 13.96

4. Cup+ Soil Weight (W2) 18.37 25.38 17.54 20.74



7. Weight of Oven Dry Soil(W =(W3-W1) 3.15 7.05 2.37 4.17



(Graph-8)

Table-11 Soil sample treated with 2.0% Fecl3




3. Weight of Cup (W1) 21.94 27.70 25.38 25.46

4. Cup+ Soil Weight (W2) 26.62 35.98 35.24 34.03








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(Graph-9)

Plastic Limit Test

Table-12 Untreated Soil Sample

S.No Particulars Trail-1 Trail-2 Trail-3

1 Cup number 1 2 3

2 Cup + Soil Weight 25.33 21.56 20.12

3 Cup + Oven Dry Soil 27.71 25.29 23.50

4 Weight of Cup 27.13 24.31 22.64

5 Weight of Water(Ww) 0.58 0.98 0.86

6 Weight of Oven Dry Soil(WS) 1.8 2.75 2.52

7 Water Content= ( Ww/Ws)*100 32.22 35.64 34.13

Average Water Content= (32.22+35.64+34.13)/3= 34%

Table-13Soil Sample treated with 0.5% Cacl2


1 Cup number 1 2 3

2 Cup + Soil Weight 21.56 20.13 25.41

3 Cup + Oven Dry Soil 23.50 24.11 27.82

4 Weight of Cup 23.02 23.13 27.26




Average water content = (32.87+32.67+30.27)/3= 33.5%

Table-14 Soil Sample treated with 1.0% Cacl2



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1 Cup number 1 2 3

2 Cup + Soil Weight 13.62 13.40 21.56

3 Cup + Oven Dry Soil 18.26 16.26 25.29

4 Weight of Cup 17.03 15.52 24.31







1 Cup number 1 2 3

2 Cup + Soil Weight 8.34 8.77 8.42

3 Cup + Oven Dry Soil 10.70 11.69 11.46

4 Weight of Cup 10.05 10.88 10.64







1 Cup number 1 2 3

2 Cup + Soil Weight 8.42 8.52 8.43

3 Cup + Oven Dry Soil 11.37 11.4 11.46

4 Weight of Cup 10.51 10.57 10.64




Average Water Content= (41.14+40.48+37.10)/3= 39.57%

Table-17 Soil Sample treated with 0.5% Fecl3



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1 Cup number 1 2 3

2 Cup + Soil Weight 13.62 13.40 13.77

3 Cup + Oven Dry Soil 18.26 16.26 16.90

4 Weight of Cup 17.03 15.52 16.07







1 Cup number 1 2 3

2 Cup + Soil Weight 13.79 13.94 13.72

3 Cup + Oven Dry Soil 16.44 16.48 16.35

4 Weight of Cup 15.72 15.83 15.63







1 Cup number 1 2 3

2 Cup + Soil Weight 26.52 26.84 25.48

3 Cup + Oven Dry Soil 29.17 28.83 28.08

4 Weight of Cup 28.51 28.30 27.25








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1 Cup number 1 2 3

2 Cup + Soil Weight 13.82 13.62 13.41

3 Cup + Oven Dry Soil 16.51 17.46 16.36

4 Weight of Cup 15.72 16.26 15.52





Plastic Index: Plasticity Index = Liquid Limit – Plastic Limit = WL - WP

Table-21

Chemical Cacl2 Fecl3

0% 42 42

0.50% 41.5 34.3

1.00% 37 32.5

1.50% 28 21

2.00% 21.7 15.7

Soil Classification

By using A-Line Chart

Taken form Highway Engineering By S.K. Khanna and C.E.G.Justo pg-273

In the plasticity chart following symbols are used:

CL= Clay of low compressibility

CH= Clay of high compressibility

ML= Silt of low compressibility

MH= Silt of high compressibility

OL= Organic soil of low compressibility

OH= Organic soil of high compressibility

Using Plasticity Chart for Unified Soil Classification System (U.S.C.S) the Sample Used for Stabilization is

classified i.e., The Liquid Limit for the Untreated Soil Sample is WL= 76%. The Plastic Limit for Untreated



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Soil Sample is WP = 37%. Corresponding Plastic Index Value is given by IP = WL - WP= 39%. From the A-

Liner chart our Sample is a Clay Sample and also our Sample comes under the zone of “CL” i.e., our sample

is clay of low compressibility.

(ii) By using Specific Gravity Table

Sand 2.63-2.67

Silt 2.65-2.7

Clay and Silty clay 2.67-2.9

Organic soil < 2.0

Specific Gravity of Untreated Soil Sample is = 2.68

Our Sample is Clay and Silty Clay that means is a combination of Clay and Silt.

Table-22Proctors Compaction Test:

S.No Observation 1 2 3 4 5 6

1 Water Content Added (%) 2% 4% 6% 8% 10% 12%

2

Mass Of Empty Mould+ Mass Of Empty Mould+Base

Plate (Gms) M1

3780 3780 3780 3780 3780 3780

3

Mass Of Empty Mould+Base Plate+ Compacted Soil

(Gms) M2

5430 5470 5520 5560 5570 5530

4 Mass Of Compacted Soil M=M1+M2 1650 1690 1740 1780 1790 1750

5 Volume Of Empty Mould (Cc) 982 982 982 982 982 982

6 Bulk Density Ρ=M/V (G/Cc) 1680 1720 1770 1810 1820 1780

7 Water Content (Ω) 0.19 0.18 0.18 0.19 0.18 0.18

8 DRY DENSITY Ρd= Ρ/(1+Ω) (G/Cc) 1.42 1.45 1.49 1.52 1.54 1.51

(Graph-10)

Swelling Pressure Test ByConsolidometer Method

Table-23 For Untreated Soil Sample



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Pressure Increment Swelling/Compressi

on

Change in Thickness of Expanded

Specimen In

kgf/cm2

In

KN/m2

0.05 4.905 23.54 3.54

Swelling

0.05 4.905 23.21 3.21mm

0.1 9.81 22.82 2.82mm

0.2 19.62 21.26 1.26mm

0.5 49.05 21.01 1.01mm

1 98.1 20.76 0.76mm

2 196.2 19.55 -0.45mm

(Graph-11)

Discussion and Test Results

The effect of adding different chemicals to the expansive soil on Atterberg limits, DFS and Strength

Properties are discussed in the following sections

Variation of Liquid limit with addition of percentage of chemical

(Graph-12)



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Variation of Plastic Limit with addition of percentage of chemical

(Graph-13)

Effect of Additives on Atterberg limits

The variation of liquid limit values with different percentages of chemicals added to the expansive soil is

presented in the Graph 21 & Table 33. It is observed that the decrease in the liquid limit is significant up to

1% of chemical added to the expansive clay for all the chemicals, beyond 1% there is a nominal decrease.

Maximum decrease in liquid limit for stabilized expansive clay is observed with the chemical FeCl3,

compared with other chemical, CaCl2. Nominal increase in plastic limit of stabilized expansive clay is

observed with increase the percentage of the chemical

Graph 23shows the variation of plasticity index with the addition of chemicals to expansive clay.

The increase in the plastic limit and the decrease in the liquid limit cause a net reduction in the plasticity

index. It is observed that, the reduction in plasticity index are 10% and 23% respectively for 1 % of CaCl2

and FeCl3 added to the expansive clay. The reduction in plasticity index with chemical treatment could be

attributed to the depressed double layer thickness due to cation exchange by calcium and ferric ions.

Effect of Additives on Atterberg limits

The variation of liquid limit values with different percentages of chemicals added to the expansive soil is

presented in the Graph 21 & Table 33. It is observed that the decrease in the liquid limit is significant up to

1% of chemical added to the expansive clay for all the chemicals, beyond 1% there is a nominal decrease.

Maximum decrease in liquid limit for stabilized expansive clay is observed with the chemical FeCl3,

compared with other chemical, CaCl2. Nominal increase in plastic limit of stabilized expansive clay is

observed with increase the percentage of the chemical

Graph 13shows the variation of plasticity index with the addition of chemicals to expansive clay.

The increase in the plastic limit and the decrease in the liquid limit cause a net reduction in the plasticity

index. It is observed that, the reduction in plasticity index are 10% and 23% respectively for 1 % of CaCl2

and FeCl3 added to the expansive clay. The reduction in plasticity index with chemical treatment could be

attributed to the depressed double layer thickness due to cation exchange by calcium and ferric ions.

Variation of DFS for different chemicals

(Graph-14)



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Effect of Additives on DFS

The variation of DFS of stabilized expansive clay with addition of different percentages of chemicals is shown

in the Graph 24 & Table 34. It is observed that the DFS is decreasing with increasing percentage of chemical

added to the expansive soil. Significant decrease in D.F.S. is recorded in stabilized expansive clay with

addition of 1% of chemical. The reductions in the DFS of stabilized expansive clay with addition of 1%

chemical are 50% and 64% for CaCl2 and FeCl3 respectively compared with the expansive clay. The reduction

in DFS values could be supported by the fact that the double layer thickness is suppressed by cation exchange

with calcium and ferric ions and with increased.

Variation of UCS for different chemicals

(Graph-15)

Effect of Chemicals on Swelling Pressure:

Variation of swelling pressure for different chemicals

(Graph-16)

Effect of Chemicals on Swelling

The Swelling pressure of the remoulded samples prepared at MDD and optimum moisture content with

addition of 0.5%, 1%, 1.5% and 2.0 % of chemicals CaCl2 & FeCl3, to the expansive soil are presented in the

Table 36. The prepared samples are tested. It is observed that the Swelling pressure of the stabilized expansive

soil is decresing with increase in percentage of chemical added to the soil.The Swelling pressure of stabilized

expansive clay is reduced by 26% and 35% when treated with 1 % chemical of CaCl2 and FeCl3

respectively. The decreasing in the swell with addition of chemicals may be attributed to the cation exchange

of CaCl2 & FeCl3 between mineral layers and due to the formation of silicate gel. The reduction in strength

beyond 1% each of CaCl2 & FeCl3 may be due to the absorption of more moisture at higher CaCl2 & FeCl3 .

CONCLUSIONS



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The following conclusions can be drawn from the laboratory study carried out in this investigation.

The liquid limit decreases as the chemical content increases and plastic limit slightly increases causing a

net decrease in plastic index. This reduction is effective up to 1% chemical content and is nominal

afterwards.

The DFS value of natural soil is very high and the addition of chemical contents decreased the value by

57% and 64% for 1% of CaCl2 and FeCl3 treatments respectively.

The swelling nature of the expansive soil is reduced considerably with the addition of the selected

chloride chemicals. For an optimum value of chemical contents the percentage decrease in the swelling

pressure are 26% and 35% for CaCl2 and FeCl3 treatments respectively.

The UCS values are increased by 177% and 203% for 1% of CaCl2 and FeCl3 treatments respectively.

From the above test results a conclusion could be made that the selected electrolytes are effective in

improving the properties of expansive soil and out of which FeCl3 is more effective.

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IJETSR

www.ijetsr.com

ISSN 2394 – 3386

Volume 4, Issue 10

October 2017

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Husk-Ash”, 13th Annual General Body Meeting of Indian Geotechnical Society.

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