7/30/2019 Babati Project Min Presentaion
1/74
PROJECT TITLE: INVESTIGATOIN OF THE CAUSES
OF FAILURE Of GRAVEL ROAD
PROPROJECT TYPE: PROBLEM SOLVING
CASE STUDY: KAMAL INDUSTRIAL ESTATE ROAD
KEREGE IN BAGAMOYO DISTRICTNAME: BABATI M. SHIHUMBILA
ADM NO:1001016992
COURSE: OD 10 CIVIL
7/30/2019 Babati Project Min Presentaion
2/74
KAMAL INDUSTRIAL ESTATE ROAD NETWOR
7/30/2019 Babati Project Min Presentaion
3/74
INTRODUCTION
Road is constructed by composite materials
that carry the weight of people and vehicle
loads. The thickness of road, width road and
type should vary based on the planned
function of the road area is designed to
provide Superior infrastructure facilities.
7/30/2019 Babati Project Min Presentaion
4/74
PROBLEM STATEMENT
water settlement to the gravel road which
cause defect like corrugation, pothole and ruts
7/30/2019 Babati Project Min Presentaion
5/74
OBJECTIVES
Main objective
To investigate causes of the road failure.
Specific objectiveTo provide suitable method of solving the
problem.
7/30/2019 Babati Project Min Presentaion
6/74
PROJECT OUTCOME
At the end of this project the causes of
Failure of road will be identified and
provide method of solve the problem.
7/30/2019 Babati Project Min Presentaion
7/74
ADOPTED METHODOLOGY
The methodology adopted in carrying out
Literature review: Through reading different
books and information obtained about
investigation of road failure
Data collection: is a term used to describe a
process of preparing and collecting data.data analysis: is done according to the data
collected from the site
7/30/2019 Babati Project Min Presentaion
8/74
Literature review
History of roads construction
Roads is primary means of communicationof people in the country. Road is very
important role in development economic. Ithas been described as veins and arteries forthe flow of the economy of thenational(1984,vazirani). Road
is built in social, cultural and political tofacilitate life of people though efficient oftransportation system.
7/30/2019 Babati Project Min Presentaion
9/74
Literature review cont
Characteristic of road
(a) it is easy to invest compared to other
mode of transportation.
(b) provide great freedom to the user
(c) have many number of user.
(d) preferable mode of transportation forshort distance.
(e) provide door to door services.
7/30/2019 Babati Project Min Presentaion
10/74
Literature review cont
Types of road
In road construction there deferent
types of road which ca be construct
according to the se of lection of road.
There two types of unpaved roads which
constructed. these area(a) Gravel road
(b) Earth road
7/30/2019 Babati Project Min Presentaion
11/74
Literature review cont
Gravel road
It is a road constructed by gravel whichcontain binding material such as clay for
construction sub base course, base courseand wearing course. These road areimprovement over the earthen road and can
take 60-100 tones of pneumatic and irontyred traffic.
7/30/2019 Babati Project Min Presentaion
12/74
Literature review cont
Component of gravel Road layers
road are:-(a)sub base course
This layer protect the imposed wheel loads and carrythe weight of base course layer.
(b)base course
The layer is should be stronger enough to carry theload.
(b)Wearing course
This layer provide a smooth surface and carry thewheel load and transfer to base course.
7/30/2019 Babati Project Min Presentaion
13/74
Literature review cont
Defects on gravel road
The defect which formed on gravel road such as:-
(a)Pothole
This is the set of hole which formed on the roadsurface.
(b)Corrugation
This defect formed and cause failure of road
when water settle to the camber.
7/30/2019 Babati Project Min Presentaion
14/74
Literature review cont
(c)RutsIs the simple operation of camber function feature.
(d)Lost of shape
The shape of camber disappear and cause watersettle or flowing Cause open to loose smoothness.
(e)Soft spot
This is the behavior the road having weak.
7/30/2019 Babati Project Min Presentaion
15/74
Literature review cont
Investigation of gravel road failure
The investigation of the road failure could bedefined as a discontinuity in a road due toformation of ruts,potholes,corrugation, lost ofshape and soft spot. a road is supported to be acontinuous stretch for smooth drive. If visibleruts, potholes, corrugation, lost of shape, andsoft spot may affect smooth drive. The effect
in smooth drive is generally regarded a roadfailure.
7/30/2019 Babati Project Min Presentaion
16/74
Literature review cont
According to these defects formed to the road
pavement during the rainfall water settle to
the road pavement. Once water has entered
to the road cause damage of pavement andcause hydraulic pressure to the road .Also
when vehicle passing over the road pavement
impact considerable sudden pressure on thewater.
7/30/2019 Babati Project Min Presentaion
17/74
Study area description
The road investigation in this study is the
gravel road 690m existing in kamal Industrial
Estate. At the time of study the road undergo
failure due to formation of ruts, potholes,corrugation, lost of shape and soft spots
which sight on portions of the road way.
7/30/2019 Babati Project Min Presentaion
18/74
Field procedure
For using chisel, hammer and tape measure
equipment was used to acquire the data .for
interval of 230m the sample taken along the
road up to 690m.
7/30/2019 Babati Project Min Presentaion
19/74
TEST TO BE DONE
(a)GRADING TEST
This is the test done to classify the the soil and
determine if it is whether gravel, sand, silt or clay
(b)ATTERBERG TEST
The test is to determine the properties of thesoil and it consists of liquid test, plastic limit andplasticity index and lastly linear shrinkage test.
7/30/2019 Babati Project Min Presentaion
20/74
TEST TO BE DONE continue
(c) COMPACTION TEST
The compaction test is to obtain therelationship between max dry density whichcan be achieve for soil depends on thedegree of compaction applied and themoisture content.
(d)CALIFORNIA BEARING RATIO TEST(BCR)
The strength of sub grade is the main factor todetermine the required thickness of pavement ofthe load.
7/30/2019 Babati Project Min Presentaion
21/74
A Particle Size Distribution Dry Sieving
-Objective of the test
- Particle size distribution analysis is a test
necessary for classification of soils, it is
present relative proportions of different sizes
of particles. This test is done to determine the
particle distribution of soil if it is gravel, sand,
silt, or clay sizes, if it is likely to control theengineering properties of the soil.
7/30/2019 Babati Project Min Presentaion
22/74
Main Principles
The preparation of the sample by wet sieving to remove siltand clay sized particles. And dry the remaining sampleafter sieving
Sample preparation
The sample is obtained by air drying for at least 12 hoursdepending on the type of the sample
A representative sample is obtained by quartering or rifflingto give a minimum mass of about 2.5kg
7/30/2019 Babati Project Min Presentaion
23/74
Procedures of the Test
Weigh the air dried sample to 0.1% of its total mass(m1),placethe sample and sieve through a 20mm sieve size, weigh thematerial retained on 20mm and sieve in respective sieve sizes
Weigh the material passing a 20mm test sieve(m2) and rifflethe sample to get a convenient fraction of about 0.5kg andweigh the fraction(m3)
Spread the riffled fraction in the large tray or bucket andcover with water
7/30/2019 Babati Project Min Presentaion
24/74
Procedures of the Test
Wash the material through a 75m sieve test to remove
silt and clay
Transfer the material the material retained on the sievetest into a tray and dry in oven at 100C to 105C for 24
hours, cool and weigh the dried sample(m4)
Sieve the dried fractions through the appropriate sieves50mm to 75m sieve test. Weigh the amount retained
on each sieve and record fines passing to 75m sieve test
7/30/2019 Babati Project Min Presentaion
25/74
Calculations
Calculate the percentage retained on each sieve
=mass of sample retained mm sieve100
total mass retained correction value
Percentage passing=100%-percentage retained for each sieve
The percentage of fines is calculated after get the percentageof passing from the table
7/30/2019 Babati Project Min Presentaion
26/74
ATTERBERG TEST
The test is to determine the properties of the
soil and it consists of liquid test, plastic limit
and plasticity index and lastly linear shrinkage
test.
cone penetrometer instruments
7/30/2019 Babati Project Min Presentaion
27/74
PROCTOR (COMPACTION) TEST
The test is used to provide a guide for
specifications on field compaction
Objective is to determine the relationship between compacted dry
density and soil moisture content.
7/30/2019 Babati Project Min Presentaion
28/74
Compaction Test
Main principles
-To determine dry density which can be
achieved of a soil depend on the degree of
compaction applied and the moisture content
-The moisture content which gives the highest
maximum dry density.
7/30/2019 Babati Project Min Presentaion
29/74
Compaction Test
The Optimum Moisture content is used forcalculating the amount of water for CBR Test
Sample Preparation Prepare sample of about 3kg of material
passing the 20mm test sieve
Test procedure
Weigh the mould, place the mould on a solidbase and attach the collar
7/30/2019 Babati Project Min Presentaion
30/74
Compaction Test
place the sample in the mould and compact eachlayer by 27 blows using a 4.5 kg rammer
The sample is compacted in 5 equal layers, after
compacting all the layers, trim the surface of themould and weigh the mould with base plateattached
Then remove the sample and follow the range of
moisture content for each point and continuecompacting until the weight of the sample andmould is decreasing
7/30/2019 Babati Project Min Presentaion
31/74
Calculations
Moisture content= mass of water 100
mass of dry soil
Bulk Density= mass of soilvolume of soil
Volume of soil=volume of mould
Dry density= Bulk Density
(1+moisture content)
7/30/2019 Babati Project Min Presentaion
32/74
CALIFORNIA BEARING RATIO (CBR) TEST
Introduction
Is the basic test used to measure the strength of soil forpavement construction The CBR is required for pavementdesign to the road construction. CBR is expressed aspercentage.
Significance of the test
The test is used to provide the relative bearing value of subgrade materials. The tests is done in laboratory soilcompacted and materials are performed usually to obtain
information that will be used for selection of materials tobe use.
7/30/2019 Babati Project Min Presentaion
33/74
Calculation
Record the penetration of 2.5mm are used for calculatingthe CBR value
CBR value (%)=P100/13.2
Record the penetration of 5.0mm are used for calculating
the CBR valueCBR value (%)=P100/20
where
p=plunger force in KN
P=(m3-m2/Vm)1000
Where, m3 is the mass of soil+mould and base plate
M2 is mass of base platein(g)
7/30/2019 Babati Project Min Presentaion
34/74
Swell calculation
S= (K-L) 100
127
S is swelling expressed as percentage
K is the dial gauge reading after four days
soaking
L is the dial gauge reading before four dayssoaking
7/30/2019 Babati Project Min Presentaion
35/74
DATA COLECTION
Data collection this is a term used to describe
a process of preparing and collecting data
7/30/2019 Babati Project Min Presentaion
36/74
Field observation
During the time of inspection the following datas wereobtained at the site
(i ) 68 pothole defects were found(ii) Ruts defects of39m along the road were found
(iii)324 corrugation defects were found
(iv)lost of shape 47m along to the road were observed
were observed
7/30/2019 Babati Project Min Presentaion
37/74
Total number of pothole
Defects No. of
Defects
Length from
(25-36)cm
Width from
(15-24)cm
Length from
(36-50)cm
Width from
(24-34)cm
Depth from
(6-17)cm
Depth from
(17-20)cm
pothole 68 41 36 27 32 30 38
The results pothole are given in Tables 1 as
summarized below:
7/30/2019 Babati Project Min Presentaion
38/74
.
pothole defects were found
7/30/2019 Babati Project Min Presentaion
39/74
The results of traffic count are given in Tables 2as summarized below:
DAY 12/12/2
012
13/12/2
012
14/12/2
012
15/12/2
012
16/12/2
012
17/12/2
012
18/12/2
012
CARS 7 10 5 15 11 15 11
p/up
and Vans
0 2 3 1 9 5 0
Lorries
over 5
tons
11 13 2 8 3 5 1
Semi
Trailer
total
vehicle
0
18
7
32
3
13
0
24
0
23
22
47
0
12
7/30/2019 Babati Project Min Presentaion
40/74
MONTHLY RAINFALL DATA FROM BAGAMOYO
years JAN FEB MARCH APRIL MAY JUNE JULY AUG SEPT OCTO NOV
2008 57.2 50.4 180.3 298.6 58.7 1O 5.2 15 7 50 9
2009 48.2 30.7 89.4 308.3 72 18 7.2 20 15 30 6
2010 67.3 47 102.4 289 63.5 25 10.2 11 8 14 10
2011 83 58.4 236.8 238 81 12 6.2 13 4 11 5.7
2012 74 40 98 198.2 66.8 7 6 20 7 30 2
7/30/2019 Babati Project Min Presentaion
41/74
RESULTS OF SOIL TEST
This report presents the actual observation
made during the site Investigation, the
Laboratory test results and gives the summary
of the data to ascertain various engineeringcharacteristics of soil.
7/30/2019 Babati Project Min Presentaion
42/74
ATTERBERG LIMITS:
The results on atterberg limits are given in Table assummarized below:
Open pit Depth(cm)
Liquid
limit%
plastic
limit%
Plasticity
Index%
OP1 30 35.0 14.0 21
OP2 30 35 17 18
OP3 28 35 20 15
7/30/2019 Babati Project Min Presentaion
43/74
COMPACTION TEST:
The results on compaction test are presented in the
table below:
Open pit Depth(mm) MDD(kg/m3) OMC(%)
OP1 300 2032 12
OP2 300 2191 8.6
OP3 280 2025 12.6
7/30/2019 Babati Project Min Presentaion
44/74
LINEAR SHRINKAGE:
In open pits OP1 to open pit OP3, the soil hadlinear shrinkage values of 10%,9% and 7% forsamples collected at depth of 300mm and280mm for OP
1 OP
3.
CBR/ SWELL values:
In open pits OP1 to open pit OP3, the soil had CBR
values of 12% to 13% and SWELL values of 0.06%to 0.09% for samples collected at depth of 30cmto the pavement.
4 0 DATA ANALYSIS
7/30/2019 Babati Project Min Presentaion
45/74
4.0 DATA ANALYSIS
Data analysis comes as the result of data
collected from the site and divided in to five
main parts which are
1. Field Observation
2. Traffic load count
3. Rainfall data
4. Laboratory test
7/30/2019 Babati Project Min Presentaion
46/74
4.1 FIELD OBSERVATION
Defects Number of defects
potholes 68
corrugation 327
Total defect 395
Length of defect along the road
Ruts 39m
Lost of shape 47m
Total Length of defect along the road is 86m
7/30/2019 Babati Project Min Presentaion
47/74
Percentage of potholes defects
So long as 68 potholes were found during field
observation as one of the data collected then
the result of this can be analyzed into
percentage as follows;
Percentage of pothole= total pothole x 100 =
Total defect
68 x 100 = 12.2%
395
7/30/2019 Babati Project Min Presentaion
48/74
Percentage of corrugation defects
Percentage of = total corrugation x 100
corrugation Total defect
327 x 100 =82.8%
395
7/30/2019 Babati Project Min Presentaion
49/74
Percentage of ruts defects
Percentage of ruts= length of rut x 100 =
Total length
39x100 = 45.3%
86
7/30/2019 Babati Project Min Presentaion
50/74
Percentage of ruts defects
Percentage of = Length of lost shape x 100
Lost of shape Total length
= 47x100 = 54.7%
86
7/30/2019 Babati Project Min Presentaion
51/74
Graph show percentage of defects
7/30/2019 Babati Project Min Presentaion
52/74
Therefore according to the analysis defects
data show that increases of corrugation, lost
of shape, and ruts cause road failure. This fact
immediately suggests that each layer of theroad structure should be designed with
utmost care.
7/30/2019 Babati Project Min Presentaion
53/74
4.2 TRAFFIC LOADING
Buy using the traffic count data the design
traffic loading of this gravel road should be
estimated. It`s done by converting the axle
load in to Equivalent factor which give thestandard axle when multiplied by number of
vehicle counted for each axle configuration.
The formation of CESAL will be calculated by
7/30/2019 Babati Project Min Presentaion
54/74
CESAL calculated
CESAL =* 365 t (1-r) -+ r
t=ESAL /day =ADT
r = growth rate
n= design period
7/30/2019 Babati Project Min Presentaion
55/74
traffic load analysisWeight of axles in
range (tones)
Mid point Number of axle(N) Equivalent factor
EF=(L/8.16)
Standard axles
=N*EF
1-3 2 74 0.0018 0.1332
3-5 4 20 0.0319 0.638
5-7 6 43 0.2507 10.7801
7-9 8 32 0.9147 29.2704
Tatol
40.8217
7/30/2019 Babati Project Min Presentaion
56/74
Calculation sheet Out put
-The Equivalent standard axle load per day
(ESAL/day) should be calculatedESAL/day =total number ESAL
Surveying days
ESAL/day =40.8217
7 ESAL/day = 5.831
-the cumulative E quivalent stardard axle load
(CESAL) is calculated by:
CESAL= 365 t (1-r) -
7
t=ESAL /day =ADT=5.8318
r = growth rate= 6%
n= design period=5
CESAL=365x 5.8318(10.06) =0.355x10 = 0.355x10
Determination of CESAL
7/30/2019 Babati Project Min Presentaion
57/74
Determination of CESAL
(E80million)Design traffic load class (E80X10) Table for traffic load class (TLC)
0.2 TLC02
0.2 to 0.5 TLC05
0.5 to 1 TLC1
1 to 3 TLC3
3 to 10 TLC10
10 to 20 TLC20
20 to 50 TLC50
7/30/2019 Babati Project Min Presentaion
58/74
Therefore this road is designed of traffic load
of 0.3355x10 put this portion of road into TLC
05 which on put in pavement thickness design
of gravel road base is 165mm
The corresponding road base thickness for the
granular base course is 193mm.thus axle
loading is higher which have causedcorrugation on gravel road.
7/30/2019 Babati Project Min Presentaion
59/74
Environmental factor like rainfall, soil erosion,
high water table and frost action cause of
gravel road failure.
7/30/2019 Babati Project Min Presentaion
60/74
4.4 DRAINAGE SYSTEMby using data collection the depth of open
Drainage is range from 0.3m to 0.4m and the
slope is very flat .In places runoff does not
reach the drain and ponds allowing to the
gravel road Surface.
slope
0.4m
GL
7/30/2019 Babati Project Min Presentaion
61/74
RECOMMENDED DEPTH OF SIDE DRAINAGE
The general requirement of side drainage is
0.6m and by referring of traffic count data
heavy load classes TLC 05-H to TLC 50-H
depth required is 1m (1999 Tanzaniapavement and material design manual).
7/30/2019 Babati Project Min Presentaion
62/74
ROAD TYPE DESING DEPTH
GENERAL REQUIREMENT
DESING DEPTH
HEAVY LOAD CLASSES
TLC 05-H TO TLC 50-H
PAVED TRUNK ROAD 0.8m 1.2m
GRAVEL ROAD 0.6m 1.0m
DESIGN DEPTH REQUIRED
7/30/2019 Babati Project Min Presentaion
63/74
DESIGN DEPTH REQUIRED
original ground level
finished road level
layer components 1.2m 1.0m
gravel road
paved road
4.4 LABORATORY TEST ANALYSIS
7/30/2019 Babati Project Min Presentaion
64/74
4.4 LABORATORY TEST ANALYSISA:Sieve and atterberg analysis
LOCATIN 230LENGTH 460LENGTH 690LENGTH
Sieve Size:(mm) %Passing. %Passing. %Passing.
19.0 100 100 100
12.40 88 94 100
10.00 76 86 86
6.30 71 80 71
4.80 62 76 60
3.350 56 70 54
2.000 48 53 41
1.180 42 44 300.600 32 26 24
0.425 26 18 19
0.300 17 12 15
0.150 13 9 11
0.075 6 4 7
With the aid of the BS 1377 USCS
7/30/2019 Babati Project Min Presentaion
65/74
With the aid of the BS 1377, USCS
soil sample classified
USCS NA SC SC AVERAGE
% Gravels 29 20 29 26
% Sand 54 68 56 59
% Fines 17 12 15 15
Liquid Limit LL (%) 35 35.4 35 35
Plastic Limit PL (%) 14 16.8 20 17
Plastic Index PI
(%) 21 19 15 18
Linear shrinkage
LS (%) 10 9 7 9
7/30/2019 Babati Project Min Presentaion
66/74
UNIFIED SOIL CLASSIFICATION SYSTEM
Major divisions group Typical names Classification for
coarse-grained soilCoarse grained
soil
Sand s with
fines(appreciabl
e amount)
S C
Clayey sand,
sand-silt
mixture
Atterberg limits
above A line with.
Fine grained
soil
Silt and sands
(liquid limit
50)
M L Inorganic silt
and very fine
sands, rock
flour, salty
clayey fine
sands
1. Determine of
sand gravel from
graine-sive curve.2. Depending on
percentage of fine
coarse-grained soil
are classified as
follows.
-Less than 5%-
GW,GP,SW,SP
-More than 12%-
GM,GC,SM,SC
-5 to 12%
borderline case
requiring dual
symbols
7/30/2019 Babati Project Min Presentaion
67/74
GRDATION CURVE
0
10
20
30
40
50
60
70
80
90
100
0.10 1.00 10.00 100.00
Percentagepassing(%)
Sieve size (mm)
Gradation Curve
230LENGTH 460LENGTH
690LENGTH
7/30/2019 Babati Project Min Presentaion
68/74
AASHTO the soil sample classified
By using the parcentage passing No.2mm,
No.425micr and No. 75micr sieve test and liquid limit
of 35% and plastic index of 18% the soil classified as
group A-7-5 which is clayey soil. General rating the
soil is poor for construction of sub grade it is cause
failure if it is use for construction of gravel road.
7/30/2019 Babati Project Min Presentaion
69/74
B: CALIFORNIA BEARING RATIO (CBR) TEST ANALYSIS
For test performed for analyzing the data of
California bearing ratio (CBR) show that the
material sample were predominantly silt,
grave and sand with little mechanical interlockand comparatively low strength of California
bearing ratio (CBR) less than 25%, despite
having maximum dry densities and optimummoisture contents of 15-18%.
7/30/2019 Babati Project Min Presentaion
70/74
CALIFORNIA BEARING RATIO(CBR)ANALYSIS
Test Hole
No.
MDD(Kg/m) OMC% 95%MDD CBR AT
95%MDD
SWELL%
1 1880 15.2 1786 14 0.11
2 1829 16.2 1738 13 0.12
3 1700 18 1615 9 0.14
7/30/2019 Babati Project Min Presentaion
71/74
DRY DENSITY AND CBR STRENGTH
1. The dry densities of the samples taken are
comparatively high, ranging from 1700 to 1829
(Kg/m). Optimum moisture contents (OMC) as one
would expect are correspondingly low.
2. Laboratory CBR values (4 day soaked) were also low
in these areas (ranging from 9 to 14%)
3. The minimum CBR Strength recommended for a base
course is 80%
5 0 CONCLUSION AND RECOMMENDATION
7/30/2019 Babati Project Min Presentaion
72/74
5.0 CONCLUSION AND RECOMMENDATION
5.1 At Kamal Industrial Estate road the base course
layer spreading and sustaining layer of the pavement
has inadequate less and the California bearing ratio
(CBR) strength is low.
5.2 This situation is aggravated by insufficient gradients
of camber this cause poor drainage design, this allow
water to pond with consequent wetting of road
material.5.3 Therefore this obviously a mojar undertaking and
for the moment I would recommend that the whole
gravel road be rehabilitated for construction
maintenance.
7/30/2019 Babati Project Min Presentaion
73/74
CONCLUSION AND RECOMMENDATION
5.4 I would proposal to excavate the side drain minimumdepth 0.6m to 1m from the ground level to avoid water make
variation table near to the sub base, base and wearing course
.However having said that to rehabilitate of gravel road will
not improve the drainage characteristic as it gives littleopportunity to increase surface gradients.
5.5 The testing carried out under study indicate that the gravel
sub base or base course would provide suitable and cheaper
alternative to replacing the existing base with 150mm leanmix with cement. the minimum MDD of 2200kg/m at OMC of
8.9% shall be applied in all rehabilitation.
REFERENCES
7/30/2019 Babati Project Min Presentaion
74/74
REFERENCES
Justo.C.G., K. K. (2011). High way Engineering.
S.P, V. c. (1984). High way and soil Engineering.
Standard publisher Delhi.
Whitlo. (2001). basic soil mechanics (4th Edition
ed.). Vazirani: person education ltd publisher.
Recommended