Initial Screening MANA 5341 Dr. George Benson [email protected].
By Josh Oliver and Fitsum Tesfa - uta.edu pp.pdfcompression test. We make dynamic and static...
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Transcript of By Josh Oliver and Fitsum Tesfa - uta.edu pp.pdfcompression test. We make dynamic and static...
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
Presenter
Presentation Notes
Grain size(mm): Gravel 76.2 to 4.75 Sand 4.75 to .075 Clay & Silt < .075
Treatment of Soil
Chemical additive were lime and cement
Two different ratios were added to soil
3%lime, 3%cement 4% lime, 4%cement
Presenter
Presentation Notes
Now we prepare three kinds of soil : (1) control or untreated soil (2) treated soil 3%lime & 3%cement (3) treated soil 4%lime & 4%cement After that we covered the soil sample with the plastic wrap and leave in a 100% moisture room for the next 24hrs.
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
Presenter
Presentation Notes
We make dynamic and static compressed soil sample for the untreated as well as for the treated soil.Totally we get three dynamic compressed and three static compressed soil sample. The dynamic compressed soil is about 2.8 inch diameter & 5.5 inch height
One dimensional swelling testone dimensional swelling test
time(min) control treated 3%lime treated 4%lime3%cement 4%cement
h= 0.983in 1.008in 1.026ind=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
-1
0
1
2
3
4
5
6
7
8
0.1 1 10 100 1000 10000 100000
%1D
SW
ELL
Time (min)
% swell vs time
control
treated 3%lime & 3%cement
treated 4%lime & 4%cement
Presenter
Presentation Notes
After 24hrs in a moisture room,we put the static compressed soil sample for swelling test in the equipment shown.Before that we take the measurements (height,diameter & weight).Then we put water to the level necessary for the purpose & take the reading for the different time .Based on the reading we are able to conclude which one of the soil sample is unstable or more stable.
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
(%)
Presenter
Presentation Notes
We are preparing three kind of soil the untreated and the two kind treated.After mixing the 200gm soil with 45%water,we put the mixed with water soil in a box(the left side picture) and leave for 24hrs in oven dried.The result as we see in the right side of the picture.the untreated soil shrinks about 15.625%,the treated soil with 3%lime & 3% cement shrinks about 6.25% and the treated soil with 4%lime & 4%cement shrinks about 1.563%.Having this information we can conclude that the treated soil is more stable than the untreated soil.
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
Presenter
Presentation Notes
From unconfined compression test ,we can simply observe that the treated soil resist maximum load before its failure.our conclusion is the treated soil is more stable under the condition we have seen.
Unconfined Compression Test
0
100
200
300
400
500
600
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140
Soil
Stre
ngth
(lb)
4%lime, 4%cement3%lime,3%cementControl
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
