Stabilization of Soil Through Chemical Alteration

By Josh Oliver and Fitsum Tesfa

Expansive soil Soil obtain in Plano,

Texas

First Step Oven dried for 24hrs

at 160 degree

The oven dried soil was crushed

After soil was crushed it was then pulverized

Classification of soil using mechanical analysis

Sieve analysis was performed on soil for 10 to 15 min

Depending on the particle size ,we concluded the ratio of gravel, sand, and clay and silt the soil contained

Classification of Soil using mechanical analysis

Hydrometer analysis, performed using the hydrometer bulb

The main idea of this experiment was to determine particulates sizes that are smaller than 0.075mm in diameter

Treatment of Soil Chemical additive

were lime and cement

Two different ratios were added to soil

3%lime, 3%cement 4% lime, 4%cement

Dynamic & static compression These two types of

compression are used in the preparation of soil samples for testing in the swell potential and unconfined compression test

One dimensional swelling testone dimensional swelling test

time(min) control treated 3%lime treated 4%lime3%cement 4%cement

h= 0.983in 1.008in 1.026in

d=2.495in d=2.498in d=2.500inw=139.05gm w=138.24gm w=137.29gm

0.1 0.097 0 0.175 0 0.299 00.5 0.102 0.508647 0.175 0 0.299 0

1 0.103 0.610376 0.175 0 0.299 02 0.106 0.915565 0.175 0 0.299 05 0.114 1.7294 0.175 0 0.299 0

15 0.125 2.848423 0.175 0 0.299 030 0.13 3.35707 0.175 0 0.299 060 0.135 3.865717 0.175 0 0.299 0

120 0.14 4.374364 0.175 0 0.299 01440 0.163 6.71414 0.175 0 0.299 0

10080 0.169 7.324517 0.177 0.198413 0.299 0

Swelling test graph

0.1 1 10 100 1000 10000 1000000

1

2

3

4

5

6

7

8

% swell vs time

control

treated 3%lime & 3%cement

treated 4%lime & 4%cement

Time (min)

%1D

SW

ELL

Soil test for linear shrinkage

4% lime, 4% cement

3% lime, 3% cement

control

soil test for linear shrinkage

control treated 3%lime treated 4%lime 3%cement 4%cement

soil(gm) 200 200 200

water 45% 45% 45%

initial length(mm) 12.8 12.8 12.8

final length(mm) 10.8 12 12.6

shrinks (mm) 2 0.8 0.2

linear shrinkage strain % 15.63 6.25 1.563

Shrinkage test graph

0

2

4

6

8

10

12

14

16

controltreated

3%lime &3%cement

treated4%lime &

4%cement

Line

ar d

efor

mat

ion

(%)

Soil samples for Unconfined Compression Test

Soil sample stayed in moisture room at 100% humidity for 7days

UCT is than ran on samples

Unconfined Compression Test

unconfined commpression test data

soil strength(lb)

F= 220 450 588

pressure(psi) P= 35.35 72.1 93.81

soil control treated 3%lime treated 4%lime PRESSURE=FORCE/AREA

3%cement 4%cement

AREA=3.141 * DIAMETER^2/4

diameter(in) D= 2.815 2.819 2.825

height(in) H= 5.63 5.669 5.583

area(in)^2 A= 6.224 6.241 6.268

0

20

40

60

80

100

control

treated3%lime &3%cement

treated4%lime &4%cement

pres

sure

(psi

)

Unconfine Compression TestPressure endured before failure

Unconfined Compression Test

0 5 10 20 30 40 50 60 70 80 90 100 110 115 120 125 130 135140 1450

100

200

300

400

500

600

4%lime, 4%cement3%lime,3%cementControl

Soil

Stre

ngth

(lb)

Time (sec)

Conclusion Soil treated or chemically altered with a 4% lime-4%

cement proved to be more stable as indicated by the test performed.

The 3% lime-3% cement treatment increased stability but not substantially compared to the 4% ratios.

Both treatments proved stronger and more stable than the control.

This research proved that lime and cement additives improved the overall qualities and performance of the soil.

Research in this field is proving invaluable to stabilization there by improving long term viability of structures.

Acknowledgments I would like to extend a special thanks to Dr. Puppala,

Aravind Pedarla, and Ranjan Rout for expertise and assistance rendered that provided me with invaluable experience also recognizing Dr. Yazdani, Dr. Daza, Dr. Weatherton, Minh Le, the University of Texas at Arlington Civil engineering Dept., University of Texas at Arlington and the National Science Foundation.

Questions