3. thilafushi -report revised

Rev-0 20/03/2021

All Information contained in this document is the property of JOSMAR Consulting Engineers.

Approval of JOSMAR Consulting Engineers is required prior to reproduction or distribution.

JOSMAR CONSULTING ENGINEERS

GEOTECHNICAL ENGINEERING DIVISION

GEOTECHNICAL AND DRAINAGE STUDY REPORT

Client:

M/s. Housing Development Corporation, Maldives.

Site:

Thilafushi, Maldives.

In Association with SIDCO Pvt Ltd, Maldives

REPORT NO: JCE/GEOTECH/2021/MAL/001

Rev-1 06 April 2021

GEOTECHNICAL AND DRAINAGE STUDY REPORT FOR THE PROPOSED PILOT ROADS PROJECT AT THILAFUSHI, MALDIVES.

1

TABLE OF CONTENT PAGE NO. INTRODUCTION 2 OBJECTIVES AND SCOPE OF WORK 5 DESCRIPTION OF THE SITE & PROJECT 6 EXPLORATION PROGRAM & TECHNIQUES 6 LABORATORY TESTING PROGRAM 8 SUBSURFACE SOIL DESCRIPTION 9 DISCUSSION ON GARBAGE FILL 14 RECOMMENDATIONS 14 Appendix - A

- Layout plan & Test locations plan

Appendix- B - Borehole Logs & Cross section of bore logs

Appendix - C - Laboratory Test Results

Appendix - D

- Field Density, Proctor, CBR tests Calculation Appendix - E - Infiltrometer test Calculation Appendix - F - Site Photos


2

INTRODUCTION The Republic of Maldives is comprised of a chain of coral atolls extending about 860 km

North to South and 80 to 120 km East to West. There are 26 atolls of varying sizes

consisting of reefs and islands. Total of 1,192 low-lying coral islands having total land

area of approximately 300 km². Although the area with the highest elevation is

approximately three meter above the mean sea level, about 80% of the nation’s total

area is less than one meter above the mean sea level. The 26 atolls are grouped into 20

administrative regions. Among the islands, 199 are inhabited and 87 are used as tourist

resorts. The geographic coordinates are 3.20 degree N, 73.22 degree E.

An atoll is an island made from coral that surrounds a lagoon either completely or

partially. Each atoll has around five to 10 inhabited islands and from 20 to 60

uninhabited islands. There are also atolls that are a single island with a surrounding

coral beach. The terrain is flat, white sandy beaches. The coastline is 644 kilometers.

For clear picture shown in the Google map in Maldives was attached in this report

(Figure - 1).

THILAFUSHI Thilafushi Island is an island in the Maldives, an artificial island created as

a municipal landfill situated to the West of Male and it is located between Kaafu

atoll's Giraavaru and Gulhifalhu of the Maldives. For clear picture shown in the Google

map in Thilafushi, Republic of Maldives was attached in this report (Figure - 2).

GEOGRAPHICAL BACKGROUND The geographic locations of certain group of islands are such that they are protected

from tsunami waves. The group of islands lying along the eastern side of Maldives, are

most prone to tsunami waves (zone 4-5), as 95 % of tsunamis that affected Maldives

generated from eastern source zone - three segments of Sumatra sub duction zone.

Situated on the Indo-Australian plate, the Maldives is tectonically very stable and a

seismic. It is located far away from high-seismicity regions. And attention is given to the

possibility of a tsunami generated from the active seismic zones around Sumatra,

Western India and in the waters west and south west of Maldives. The water of ocean


3

lying south of Maldives and the Carlsberg oceanic ridge zone, which has a high level of

seismic activity. The seismic hazard Zone in Maldives was shown below.

Seismic Hazard Zone

§ THILAFUSHI

Earthquake is a shaking of the ground caused by the sudden dislocation of material

within the Earth's outer layer or crust. When forces pushing on a mass of rock overcome

the friction holding the rock in place and blocks of rock slip against each other an

earthquake may occur. Some earthquakes are so slight, and some occur in such remote

areas, that they are barely felt. Others are so violent that they cause extensive damage.

The earthquake prone areas in Maldives are shown in below.


4

Earthquake prone areas in Maldives

The Seismic Hazard Zone and Earthquake prone areas are shown in varies zones are

marked in the above figures. In this figure, it is understood that the proposed

construction is located in Thilafushi; Maldives is occurring in zone -5 in Seismic Hazard

Zone and zone- 1 in Earthquake prone area. The structural engineer should take care of

design consideration for the proposed structure.


5

This report presents the results of the geotechnical investigation and drainage study

carried out by JOSMAR Consulting Engineers- Geotechnical Engineering Division, for

the proposed Pilot Road Project, located at Thilafushi, Maldives.

This work was authorized by the Client M/s. Housing Development Corporation, Maldives. Standard penetration tests were carried out at six boreholes drilled up to a depth of

6.00m, 4.50m, 9.00m & 7.50m below the existing ground level respectively.

The investigation consists of drilling six boreholes, five infiltrometer tests, three field

density tests, soil sampling, field and laboratory testing and preparation of a

Geotechnical Report for the proposed Pilot Road project at Thilafushi, Maldives.

OBJECTIVES OF THE STUDY It is understood that HDC has the following objectives.

1. To develop a safe and well-suited road surface for the vehicles operating in Thilafushi

2. To incorporate a well incorporated drainage system for the island.

3. To provide a safe and convenient pedestrian walkway for the residents of Thilafushi.

SCOPE OF WORK The scope of this investigation is to: 1. Determine the soil profile along the pilot road,

2. Conduct three field density tests, to observe the percent compaction of top layer,

3. Conduct five double ring infiltrometer tests, to determine the rate of infiltration,

4. Collect soil samples and transport to Josmar laboratory at Chennai.

5. Conduct two modified Proctor density test at laboratory.

6. Provide technical discussions and recommendations.

Six (6) boreholes were drilled to a maximum depth of 9.00m.

Soil samples were collected for visual identification, laboratory testing and soil

classification.

Boreholes, Field density, Infiltrometer test locations are presented in Appendix- A.

Borehole logs and the summary of bore logs are presented in Appendix- B.


6

Laboratory test results are presented in Appendix- C.

Field density, Proctor test, CBR test calculations are presented in Appendix- D.

Infiltrometer test calculations are presented in Appendix- E.

Site photos are presented in Appendix- F.

DESCRIPTION OF THE SITE The site for the proposed Pilot Roads project is located at Thilafushi, Maldives.

The top surface of the site is at the same level of adjacent road.

EXPLORATION PROGRAM & TECHNIQUES After the visual inspection of the site, the subsurface investigation was performed from

05th to 13th March 2021 using a rotary drilling rig as mentioned below.

BH - 1 was started on 05th March 2021 and completed on 06th March 2021






Boreholes were drilled at the site as shown in the AutoCAD drawing in order to obtain

the average soil profile of the site. Rotary drilling was performed using (wash boring

techniques) water as drilling fluid in the sub soil the boreholes was drilled up to the

required depth. Field tests and sampling were conducted in accordance with British

standards.

Standard penetration test (SPT) was conducted using split barrel sampler at top layers

to determine the “N” value of the soil layers. SPT was conducted at every 1.50m depth

intervals in each borehole to determine penetration resistance as per BS 1377-9: 1990.

Number of blows was recorded for every 15cm penetration for a total of 45cm

penetration. The number of blows required to drive the sampler for 30 cm apart from the

seating drive is termed as penetration resistance “N”. The SPT value at the top layers in

each borehole at different depths has been recorded in the bore logs.

The fieldwork was carried out under the close supervision of our site engineer.


7

Double Ring Infiltrometer

The double ring infiltrometer is a simple instrument used for determining water infiltration

of the soil (according to ASTM D3385-03 and DIN 19682 page 7).

The rings are partially inserted into the soil and filled with water, after which the speed of

infiltration is measured. The double ring limits the lateral spread of water after infiltration.

The standard set consists of two pairs of inner and outer rings, allowing synchronic

measuring. This saves time and produces reliable average data.

The double ring infiltrometer is suitable for almost any type of soil and is applied in

irrigation and drainage projects, groundwater and infiltration basins, in optimizing water

availability for plants and to determine the effects of cultivation.

Some examples of constant infiltration rates (or near-saturated hydraulic conductivity)

for different soil types are listed in the table.

Soil type Constant infiltration rate

(mm/hr)

Sand > 30

Sandy loam 20 - 30

Loam 10 - 20

Clayey loam 5 - 10

Clay 1 - 5

See Bouwer (1986), ILRI (1974), Ward & Robinson (1990) for further information concerning soil

water, infiltration and the use of the double ring infiltrometer.


8

LABORATORY TESTING PROGRAM All the extracted soil samples were brought to the Geotechnical & Materials Testing

Laboratory of JOSMAR Consulting Engineers for further examination in accordance with

British Standard (BS).

Soil samples were subjected to the physical tests in accordance to BS Code.

The relevant tests carried out include the following.

1) Natural Moisture Content (BS 1377 Part- 2)

2) Sieve Analysis (BS 1377 Part- 2)

3) Specific Gravity (BS 1377 Part- 2)

4) Direct Shear test (BS 1377 Part- 7)

5) Proctor Compaction test (BS 1377 Part- 4)

6) CBR test (BS 1377 Part- 4)

Since no plastic soil was encountered, Atterberg’s limits, tri axial compression test,

consolidation test and unconfined compression tests are not applicable.

The laboratory test results are given in Appendix- C.

Modified Proctor Compaction Test Results:

Sample No. Maximum Dry Density,

g/cc Optimum Moisture

Content, %

Sample-1 1.72 13.69

Sample-2 1.71 15.93

CBR Test Results:

Sample- 1 CBR Value at 2.5mm penetration 13.50 %

CBR Value at 5.0mm penetration 17.52 %

Sample- 2 CBR Value at 2.5mm penetration 11.02 %

CBR Value at 5.0mm penetration 14.01%

Average CBR value of 15.76% (at 5mm penetration) shall be considered for design purpose.


9

SUBSURFACE SOIL DESCRIPTION Based on boreholes information, sub surface soil profile of the proposed Pilot Road

work is given below:

BH-1 0.00 - 6.00m Brownish White, Sandy soil with limestone and calcareous stone

(GP, SP& SM), dense to very dense relative density

BH-2

0.00 - 1.00m Garbage fill- Construction debris

1.00 - 4.50m Whitish, Sandy soil with limestone (SM & SP), dense to very dense

BH-3 0.00 - 5.50m Garbage fill- Construction debris

5.50 - 9.00m Whitish, Sandy soil with limestone (SP-SM), dense to very dense


1.50 - 6.00m Brownish White, Poorly graded sand, little fines (SP), medium dense to

very dense relative density


2.50 - 7.50m Brownish White, Poorly graded sand, little fines (SP),

dense to very dense relative density

BH-6 0.00 - 6.00m Brownish White, Poorly graded sand with fines (SP-SM),

dense to very dense relative density

Garbage fill consists of waste materials such as polythene bags, steels, cloths,

boulders, construction debris etc.

At BH-1, the top layer consists of residual soil. This layer is followed by Brownish White,

Sandy soil with limestone and calcareous stone (GP, SP & SM), where its SPT results

indicate dense to very dense relative density.


10

At BH-2, the top layer consists of garbage fill found up to a depth of 1.00m. This layer is

followed by Whitish, Sandy soil with limestone (SM & SP), where its SPT results indicate

dense to very dense relative density.

At BH-3, the top layer consists of garbage fill found up to a depth of 5.50m, where its

SPT results indicate loose to medium dense relative density. This layer is followed by

Whitish, Sandy soil with limestone (SP-SM), where its SPT results indicate dense to

very dense relative density.

At BH-4, the top layer consists of garbage fill up to a depth of 1.50m where its SPT

result indicates medium dense relative density. This layer is followed by Brownish

White, Poorly graded sand, little fines (SP), dense to very dense relative density.

At BH-5, the top layer consists of garbage fill found up to a depth of 2.50m, where its

SPT result indicates loose relative density. This layer is followed by Brownish White,

Poorly graded sand, little fines (SP), where its SPT results indicate dense to very dense

relative density.

At BH-6, the top layer consists of residual soil. This layer is followed by Brownish White,

Poorly graded sand with fines (SP-SM), where its SPT results indicate dense to very

dense relative density.

The soil samples in all the six bore logs at different depths are shown below in the

photographs.


11

BH-1 at 1.00 to 6.00 m Depth

BH-2 at 1.50 to 4.50 m Depth


12

BH-3 at 1.50m to 9.00 m Depth

BH-4 at 1.50m to 6.00 m Depth


13

BH-5 at 1.50m to 7.50m Depth

BH-6 at 1.50m to 6.00m Depth


14

GROUND WATER Water was encountered at 1.00m depth at BH-1,5,6 and 1.50m at BH-2,3,4 below the

existing ground level during the time of field investigation. However it may fluctuate due

to the tidal variations.

Discussion on garbage fill area: Garbage fill consists of waste materials such as steels, cloths, boulders, polythene

bags, construction debris etc.

. Considering the movement of heavy vehicles, the road section (except BH-1 and BH-6,

remaining boreholes) area shall be improved by

1. Replacement of garbage fill by soil mixed with calcareous gravel with structural

geogrid layer at bottom, (or)

2. Mini stone columns supported by structural geogrids.

Recommendations For boreholes BH- 2,3,4,5 1. Ground improvement by soil mixed with calcareous gravel with structural Geogrid layer at bottom - Excavate up to 1.50m depth, below that backfilling by igneous rock stones for 20cm

thickness.

- After rolling, four compacted layers of 25cm thickness consists of gravel-sand mixture

shall be placed.

- Percentage compaction shall be a minimum of 90% at bottom two layers and minimum

of 95% at top two layers.

- Balance top 0.50m shall be the designed road section.

Alternate Recommendations 2. Mini stone columns supported by structural Geogrids - Excavation shall be carried out up to a depth of 0.50m.

- Mini stone columns shall be installed below 0.50m to 2.50m depth.

- Stones shall be of igneous origin.


15

- After installation of mini stone columns, one layer of structural geogrid (20 kN/m) shall

be provided before laying the road section.

- Diameter and spacing shall be designed by the execution contractor.

At BH-1 and BH-6 locations, there is no garbage fill.

Hence, no need of ground improvement at these locations.

Excavate up to a depth 0.50m and compact the natural ground by heavy rolling followed

by field compaction control of 95%.

Drainage Considerations

In view of the results of double Ring Infiltro-meter test results at all the locations, it is

inferred that the nature of water movement through the topsoil layer is high. Shallow

water table has been noted at a depth of 1m below ground level. Thilafushi is a

reclaimed land with quay wall or sheet piling as shore protection measure on large parts

at both sides of the Island. This makes it very difficult to drain the water on both sides of

the road. Hence a part of rainwater is expected to pass through the soil pores and reach

the ground water table in a faster manner while storm water drainage shall be provided

to collect the storm water to drain the water under gravity to the sea. The following

measures shall be considered.

1. Drainage to the ground shall be enhanced by provision of thin gravel layer at top

at the shoulders with vegetable cover with protection for soil erosion by

Geomembrane if necessary.

2. Gravity drains to the sea

This method is also suitable during flash floods, as the huge quantity of water

shall be collected at the side drains to divert the water into the sea by provision of

sufficient storm water drains, on both sides of the road, through drainage pipes.

APPENDIX- A

TEST LOCATIONS PLAN

APPENDIX- B

BOREHOLE LOGS &

CROSS SECTION OF BORE LOGS

Ele . Of G.L : 0.00m

Client : M/s. Housing Development Corporation Water Table : 1.00mProject : Type Of Boring : Rotary

Location : Thilafushi Dia of Boring : 150mm

B.H. No : 1 Started on : 05.03.2021

Final Depth : 6.00m Ended on : 06.03.2021

Address :

Depth G

(m) W

L /Consistency

15 17 18 35

19 24 27 51

23 26 29 55

24 35 35 70

44 45 60 105

Ditto

Ditto

N- V

alue

15 -3

0 cmSOIL DESCRIPTION

Ditto

Very dense

Very dense

30 -4

5 cm Relative Density

Dense

Very dense

Very dense

BORE HOLE LOG


SYMBOL

SPT COUNT

0 -1

5 cm

Pilot Roads

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8

BH-1 terminated at a depth of 6.00m in very dense strata.

Brownish White, Sandy soil (GP, SP) with limestone and calcareous stone

Brownish White, Silty sands with lime stone (SM)


Client : M/s. Housing Development Corporation Water Table : 1.50mProject : Type Of Boring : Rotary


B.H. No : 2 Started on : 08.03.2021


Address :

Depth G

(m) W

L /Consistency

20 21 24 45

23 34 38 72

37 49 58 107

Ditto Very dense

Ditto Very dense

Relative Density

Garbage fill- Construction debris

Dense

BORE HOLE LOG

Pilot Roads


SYMBOL

SPT COUNT

SOIL DESCRIPTION

0 -1

5 cm

15 -3

0 cm

30 -4

5 cm

N- V

alue

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8


Whitish, Sandy soil (SM & SP) with limestone


Client : M/s.Housing Development Corporation Water Table : 1.50mProject : Type Of Boring : Rotary


B.H. No : 3 Started on : 09.03.2021


Address :

Depth G

(m) W

L /Consistency

2 3 5 8

3 5 7 12

8 10 12 22

17 22 24 46

26 38 40 78

39 48 54 102

Ditto Very dense

Ditto Medium dense

Very denseDitto

Dense

Ditto Medium dense

Loose

BORE HOLE LOG

Pilot Roads


SYMBOL

SPT COUNT


SOIL DESCRIPTION

0 -1

5 cm

15 -3

0 cm

30 -4

5 cm

N- V

alue Relative Density

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8


Whitish, Silty sand (SM) with gravels and limestone




B.H. No : 4 Started on : 12.03.2021


Address :

Depth G

(m) W

L /Consistency

7 9 13 22

17 21 22 43

29 33 42 75

47 52 59 111

Very denseDitto

Dense

Ditto Very dense

N- V


Medium dense


BORE HOLE LOG

Pilot Roads


SYMBOL

SPT COUNT

SOIL DESCRIPTION

0 -1

5 cm

15 -3

0 cm

30 -4

5 cm

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8


Brownish White, Poorly graded sand, little fines (SP)




B.H. No : 5 Started on : 10.03.2021


Address :

Depth G

(m) W

L /Consistency

2 4 5 9

`

14 17 18 35

24 29 34 63

36 41 45 86

46 52 57 109

Ditto

Ditto Very dense

Ditto Very dense

Very dense

Dense

Relative Density

Garbage fill- Construction debris Loose

BORE HOLE LOG

Pilot Roads


SYMBOL

SPT COUNT

SOIL DESCRIPTION

0 -1

5 cm

15 -3

0 cm

30 -4

5 cm

N- V

alue

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8






B.H. No : 6 Started on : 11.03.2021


Address :

Depth G

(m) W

L /Consistency

30 54 64 118

17 21 25 46

29 33 39 72

37 46 58 104

0 -1

5 cm

15 -3

0 cm

30 -4

5 cm

N- V


Very dense

BORE HOLE LOG

Pilot Roads


SYMBOL

SPT COUNT

SOIL DESCRIPTION

Dense

Ditto Very dense

Ditto Very dense

Ditto

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

8


Brownish White, Poorly graded sand with fines (SP-SM)

Client : M/s.Housing Development Corporation

Project : Pilot Road

Location : Thilafushi

: 1.50m

SPT SYM SPT SYM SPT SYM SPT SYM SPT SYM SPT SYM

35

45 118

51

55 72 12 43 35 46

70 107 22 75 63 72

105 46 111 86 104

78 109

102

BH-2

9.00m

BH-6BH-5

7.50m

Sandy soil

4.50m

922

6.00m

Garbage fill/ Filling soil

8.0

8.5

9.0

9.5

BH-1 BH-4

4.0

5.0

5.5

6.0

8

1.0

6.5 6.00m

SUMMARY OF BORE HOLE LOGS

10.0

Water Table

Depth (m)BH-3

0.5

2.0

7.5

7.0

4.5

6.00m

2.5

3.0

3.5

1.5 8

APPENDIX- C

LABORATORY TEST RESULTS

PHYSICAL ANALYSIS OF SOIL- BH- 1


DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.00 13 NON PLASTIC GP 75 8 12 3 2

2.00 21 NON PLASTIC SP 2 24 68 1 5

3.00 21 NON PLASTIC SP 2 28 64 1 5

4.50 14 NON PLASTIC SM 47 1 11 20 21

6.00 24 NON PLASTIC SM 7 1 17 56 19

DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.50 23 NON PLASTIC SM 22 5 34 27 12

3.00 26 NON PLASTIC SP 44 5 29 17 5

4.50 25 NON PLASTIC SP 39 5 35 17 4



DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.50 25 NON PLASTIC SP-SM 1 - 49 41 9

3.00 25 NON PLASTIC SP-SM 4 1 37 51 7

4.50 18 NON PLASTIC SP-SM 8 3 30 49 10

6.00 16 NON PLASTIC SM 15 12 40 21 12

7.50 18 NON PLASTIC SP-SM 22 13 32 15 8

9.00 17 NON PLASTIC SP-SM 21 14 38 17 10

DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.50 21 NON PLASTIC SP-SM 2 3 49 39 7

3.00 21 NON PLASTIC SP 3 - 45 47 5

4.50 20 NON PLASTIC SP 1 - 46 49 4

6.00 20 NON PLASTIC SP 1 1 22 73 3



DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.50 25 NON PLASTIC SP 5 4 63 24 4

3.00 23 NON PLASTIC SP - - 66 31 3

4.50 26 NON PLASTIC SP - - 28 67 5

6.00 26 NON PLASTIC SP 2 1 48 45 4

7.50 25 NON PLASTIC SP - 1 47 48 4

DEPTH M

WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

1.50 23 NON PLASTIC SP 27 13 37 18 5

3.00 24 NON PLASTIC SP-SM 20 5 34 32 9

4.50 20 NON PLASTIC SP-SM 23 5 32 31 9

6.00 18 NON PLASTIC SP-SM 12 5 37 35 11

PHYSICAL ANALYSIS OF SOIL- FDTs

PHYSICAL ANALYSIS OF SOIL- Proctor Samples

ABBREVIATION:

WN = Natural Moisture content (%) WL = Liquid limit (%)

WP = Plasticity Limit (%)

IP = Plasticity Index (%)

F.S.I = Free Swell Index (%)

IS = Indian Standard Classification

SP = Poorly graded sand

SM = Silty sand

GP = Poorly graded gravel

Location WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

FDT-1 9 NON PLASTIC SM 15 6 34 28 17

FDT-2 5 NON PLASTIC SP-SM 23 5 31 33 8

FDT-3 6 NON PLASTIC SM - - 15 72 13

Location WN%

WL%

WP%

IP %

FSI% IS GRAVEL

%

COARSE SAND

%

MEDIUM SAND

%

FINE SAND

%

SILT +

CLAY%

PS-1 15 NON PLASTIC SM 5 3 27 44 21

PS-2 14 NON PLASTIC SM 2 1 19 66 12

SPECIFIC GRAVITY OF SOILSAMPLES

Sl. No. Bore Hole No. Depth, m Specific Gravity

1 BH-1 2.00 2.62

2 BH-2 1.50 2.65

3 BH-3 6.00 2.65

4 BH-4 3.00 2.62

5 BH-5 3.00 2.61

6 BH-6 3.00 2.63

Correlations of SPT N values with Common properties of soils A) Granular Soil

Standard Penetration No., SPT N

Description Relative Density,

Dr % Approx. Angle of

Internal Friction, Φq Approx. Rang of Most.

Unit Wt.,ע kN/m3 �

� 4 4-10

10-30 30-50

! 50

Very loose Loose Medium Dense Dense Very Dense

� 20 20-40 40-60 60-80

! 80

� 29 29-30 30-36 36-41

! 41

11-16 14-18 17-20 17-22 20-29

B) Cohesive Soil

Standard Penetration No.,

SPT N Description

Unconfined Compressive Strength, kPa

Approx. Rang of Most. Unit Wt., עkN/m3

� 2 2-4 4-8 8-15

15-30

! 30

Very Soft Soft

Firm (medium) Stiff

Very Stiff Hard

0-25 25-50

50-100 100-200 200-400

! 400

14.4-16 16-17.4

17.6-19.2 19.2-20.8 20.8-22.4

! 20

Note: These values are most appropriate values in general. However, the soil properties vary between sites to site and hence it shall be used only for guidance

Client M/s.Housing Development CorporationProject

BH # BH-1

Mat'l. Descp. Depth (m) 2.00

Angle of Internal Friction 38 Moisture Content ( % ) 21.0 'Cohesion, C ( Kg/cm2 ) 0

Normal ShearStress Stress0.000 0.0000.500 0.3711.000 0.7611.500 1.152

Direct Shear Test

Pilot Road Work


0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2

NORMAL STRESS, Kg/cm2

DIRECT SHEAR TEST


BH # BH-2




Direct Shear Test

Pilot Road Work

Whitish, Silty sand, poorly graded sand silt mixtures (SM)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2


DIRECT SHEAR TEST


BH # BH-3




Direct Shear Test

Pilot Road Work

Whitish, Silty sand, poorly graded sand silt mixtures (SM)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2


DIRECT SHEAR TEST


BH # BH-4




Direct Shear Test

Pilot Road Work


0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2


DIRECT SHEAR TEST


BH # BH-5




Direct Shear Test

Pilot Road Work


0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2


DIRECT SHEAR TEST


BH # BH-6




Direct Shear Test

Pilot Road Work

Brownish White, Poorly graded sand with fines (SP-SM)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00

SHEA

R ST

RESS

, Kg/

cm2


DIRECT SHEAR TEST

APPENDIX- D

FILED DENSITY, PROCTOR, CBR TEST CALCULATION

Client Project Location

Sl.No. FDT-1 FDT-2 FDT-3

1 2714 2736 2377

2 960 960 960

3 1754 1776 1417

4 1020.50 1020.50 1020.50

5 1.72 1.74 1.39

6 58.59 63.12 59.93

7 364.01 377.18 250.54

8 338.80 362.59 239.51

9.00 4.87 6.14

10 1.58 1.66 1.31

11 0.66 0.58 1.00

12 35.63 22.05 16.05

13 1.72 1.72 1.72

14 91.68 96.48 76.06

DETERMINATION OF DRY DENSITY OF SOIL IN-PLACE(CORE CUTTER METHOD) IS: 2720- PART- XXIX

Void ratio e = ((G x Yw) / Yd )-1

Degree of saturation, S= (wxG) /e, %

Maximum dry density, Yd = ((GxYw) / (1+Gw)), g/cc

Percentage of Compaction, %

9

Weight of core-cutter + wet soil (Ws), g

Weight of container + wet soil (W2), g

w = (W2-W3) / (W3-W1)x 100

In -situ Dry density Yd= (100xYb) / (100+w),

g/cc

In-Situ Water content, %

Weight of core-cutter (Wc), g

Weight of wet soil (Ws-Wc), g

Volume of core-cutter (Vc), cc

Weight of container + dry soil (W3), g

Determination of water content:

: Pilot Road Work

Bulk density,Yb = (Ws-Wc )/ Vc, g/cc

Weight of container (W1), g

Test Locations

: M/s. Housing Development Corporation

: Thilafushi

Client : M/s. Housing Development Corporation 20.03.2021Project : Pilot Road WorkLocation : Thilafushi

Soil Sample taken = 5 kgDiameter of mould = 10 cmHeight of mould = 13 cmWeight of mould+ Base plate, W1 = 4499 gVolume of mould, V = 1021.02 cm3

Height of fall = 450 mmWeight of rammer = 4.9 kgNumber of blows = 25Number of layers = 5Specific Gravity of soil, Gs = 2.60Water density, γw = 1Proctor Test No. PS-1

1 2 3 4 51 Wt. of mould+base+Compacted soil (w2), g 6266 6341 6440 6500 65252 Weight of compacted soil (w2-w1), g 1767 1842 1941 2001 20263 Wet density γb = ((w2-w1)/v), g/cm3 1.73 1.80 1.90 1.96 1.984 Dry density γd = (γb/(1+(w/100))), g/cm3 1.64 1.67 1.71 1.72 1.715 Void ratio e = ((Gsγw)/γd)-1 0.58 0.55 0.52 0.51 0.52

Water Content:6 Weight of Container, g 21.98 21.91 21.91 21.95 21.907 Weight of Container + Wet soil (g) 64.55 65.19 66.93 75.01 80.458 Weight of Container + dry soil (g) 62.36 62.09 62.45 68.62 72.479 Weight of water Ww, (g) 2.19 3.1 4.48 6.39 7.98

10 Weight of dry soil Ws, (g) 40.38 40.18 40.54 46.67 50.5711 Water content (w) = ((Ww/Ws)x100), % 5.42 7.72 11.05 13.69 15.78

12Zero air void density γz = ((Gsγw)/(1+(wGs)/100))) 2.28 2.17 2.02 1.92 1.84

Results: Maximum Dry Density = 1.72 g/cc Optimum Moisture Content = 13.69 %

DETERMINATION OF WATER CONTENT- DRY DENSITY RELATION USING HEAVY COMPACTION, AS PER IS:2720 (PART-8)- 1983 (BY HAND)

Dry Density- Water Content Graph for PS-1

Sl.No. Description

CALCULATIONS

Trials

1.631.641.651.661.671.681.691.701.711.721.73

0.00 5.00 10.00 15.00 20.00

Dry

Den

sity

Client : M/s. Housing Development Corporation 20.03.2021Project : Pilot Road WorkLocation : Thilafushi

Soil Sample taken = 5 kgDiameter of mould = 10 cmHeight of mould = 13 cmWeight of mould+ Base plate, W1 = 4499 gVolume of mould, V = 1021.02 cm3

Height of fall = 450 mmWeight of rammer = 4.9 kgNumber of blows = 25Number of layers = 5Specific Gravity of soil, Gs = 2.62Water density, γw = 1Proctor Test No. PS-2

1 2 3 4 51 Wt. of mould+base+Compacted soil (w2), g 6192 6310 6374 6525 65052 Weight of compacted soil (w2-w1), g 1693 1811 1875 2026 20063 Wet density γb = ((w2-w1)/v), g/cm3 1.66 1.77 1.84 1.98 1.964 Dry density γd = (γb/(1+(w/100))), g/cm3 1.59 1.64 1.66 1.71 1.645 Void ratio e = ((Gsγw)/γd)-1 0.65 0.60 0.58 0.53 0.60

Water Content:6 Weight of Container, g 25.02 29.82 26.83 29.34 28.137 Weight of Container + Wet soil (g) 77.80 71.12 75.07 80.87 88.728 Weight of Container + dry soil (g) 75.55 67.90 70.44 73.79 78.779 Weight of water Ww, (g) 2.25 3.22 4.63 7.08 9.95

10 Weight of dry soil Ws, (g) 50.53 38.08 43.61 44.45 50.6411 Water content (w) = ((Ww/Ws)x100), % 4.45 8.46 10.62 15.93 19.65

12Zero air void density γz = ((Gsγw)/(1+(wGs)/100))) 2.35 2.14 2.05 1.85 1.73

Results: Maximum Dry Density = 1.71 g/cc Optimum Moisture Content = 15.93 %

Dry Density- Water Content Graph for PS-2

DETERMINATION OF WATER CONTENT- DRY DENSITY RELATION USING HEAVY COMPACTION, AS PER IS:2720 (PART-8)- 1983 (BY HAND)

CALCULATIONS

Sl.No. Description Trials

1.58

1.60

1.62

1.64

1.66

1.68

1.70

1.72

0.00 5.00 10.00 15.00 20.00 25.00

Dry

Den

sity

Hand methodWeight of rammer = 4.90 kgFall of height = 450 mmNumber of layers = 3 layersNumber of blows = 56 blows

ObservationWeight of mould = 3.214 kgHeight of mould = 17.3 cmDiameter of mould = 15.3 cm

Model Calculation

=

=

Load, kg05

1284

149185250305320345360410455495550

Penetration Depth (mm)

2.55

RESULT :

Unsoaked Condition,For γd = 1.72 g/cm3 (MDD) and Optimum Moisture Content (OMC) = 13.7 %

= 13.50 %= 17.52 %

105 2055

CBR value at 2.5mm penetration CBR value at 5.0mm penetration

Unit Standard load kg/cm2

Total Standard Load kgf

70 1370

6.06.57.0

5.5

0.00.51.01.52.02.53.03.54.04.55.0

CBR @ 5.0mm penetration Actual load in kg taken by soil x100Standard load @ 5.0mm penetration

Penetration, mm

Laboratory CBR Test (Unsoaked) Calculation- Sample-1


The C.B.R. values are usually calculated for penetration of 2.5 mm and 5 mm. Generally the

C.B.R. value at 2.5 mm will be greater than at 5 mm and in such a case/the former shall be taken

as C.B.R. for design purpose

0

100

200

300

400

500

600

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0

CBR curve (Unsoaked)- Sample-1

PENETRATION IN (mm)

LOA

D (k

g)

Hand methodWeight of rammer = 4.90 kgFall of height = 450 mmNumber of layers = 3 layersNumber of blows = 56 blows

ObservationWeight of mould = 3.214 kgHeight of mould = 17.3 cmDiameter of mould = 15.3 cm

Model Calculation

=

=

Load, kg029

50120151180230255270288340365396440

Penetration Depth (mm)

2.55

RESULT :

Unsoaked Condition,For γd = 1.71 g/cm3 (MDD) and Optimum Moisture Content (OMC) = 15.9 %

= 11.02 %= 14.01 %

105 2055

CBR value at 2.5mm penetration CBR value at 5.0mm penetration

Unit Standard load kg/cm2

Total Standard Load kgf

70 1370

6.06.57.0

5.5

0.00.51.01.52.02.53.03.54.04.55.0


Penetration, mm

Laboratory CBR Test (Unsoaked) Calculation- Sample-2


The C.B.R. values are usually calculated for penetration of 2.5 mm and 5 mm. Generally the

C.B.R. value at 2.5 mm will be greater than at 5 mm and in such a case/the former shall be taken

as C.B.R. for design purpose

0

50

100

150

200

250

300

350

400

450

500

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0

CBR curve (Unsoaked)- Sample-2

PENETRATION IN (mm)

LOA

D (k

g)

APPENDIX- E

INFILTROMETER TEST CALCULATION

Project :Pilot R

oad work

Location:Thilafushi

Test- 1N

earby BH-2

07.03.2021C

DE

FG

H

hrm

insec

After filling R

eading (mm

)0

130Start=0

Start=00

00

01

1221

18

8480

82

1152

17

7420

153

1123

13

3180

184

1094

13

3180

21

5104

51

55

30026

6102

61

22

12028

7101

71

11

6029

8100

81

11

6030

998

91

22

12032

1096

101

22

12034

Infiltration (from

B),

mm

Infiltration C

apacity, m

m/m

in

DETER

MIN

ATION

OF W

ATER IN

FILTRATIO

N O

F SOIL (D

ouble Ring Infiltrom

eter) (ASTM

D3385-03 &

DIN

-1962 Page-7)

Infiltration C

apacity, m

m/hr

Cum

ulative Infiltration,

mm

Cum

ulative tim

e, min

Time Interval

(from A), m

in

Note: Short interval or longer interval depending on the type of soil

AB

Before filling

Reading (m

m)

Time

Reading

Water Level

130

Project :Pilot R

oad work

Location:Thilafushi

Test- 2N

earby BH-3

09.03.2021C

DE

FG

H

hrm

insec

After filling R

eading (mm

)0

130Start=0

Start=00

00

01

1261

14

4240

42

1242

12

2120

63

1223

12

2120

84

1214

11

160

9

5120

51

11

6010

6120

61

00

010

7118

71

22

12012

8116

81

22

12014

9115

91

11

6015

10115

101

00

015


Before filling

Reading (m

m)

130 DETER

MIN

ATION

OF W

ATER IN

FILTRATIO

N O

F SOIL (D


eter) (ASTM

D3385-03 &

DIN

-1962 Page-7)

AB

Time

Reading

Water Level

Cum

ulative tim

e, min

Time Interval

(from A), m

inInfiltration (from

B),

mm

Infiltration C

apacity, m

m/m

in

Infiltration C

apacity, m

m/hr

Cum


mm

Project :Pilot R

oad work

Location:Thilafushi

Test- 3N

earby BH-4

12.03.2021C

DE

FG

H

hrm

insec

After filling R

eading (mm

)0

130Start=0

Start=00

00

01

1271

13

3180

32

1252

12

2120

53

1243

11

160

64

1234

11

160

7

5122

51

11

608

6121

61

11

609

7120

71

11

6010

8119

81

11

6011

9118

91

11

6012

10117

101

11

6013


Before filling

Reading (m

m)

130 DETER

MIN

ATION

OF W

ATER IN

FILTRATIO

N O

F SOIL (D


eter) (ASTM

D3385-03 &

DIN

-1962 Page-7)

AB

Time

Reading

Water Level

Cum

ulative tim

e, min

Time Interval

(from A), m


B),

mm

Infiltration C

apacity, m

m/m

in

Infiltration C

apacity, m

m/hr

Cum


mm

Project :Pilot R

oad work

Location:Thilafushi

Test- 4N

earby BH-6

12.03.2021C

DE

FG

H

hrm

insec

After filling R

eading (mm

)0

120Start=0

Start=00

00

01

1171

13

3180

32

1152

12

2120

53

1143

11

160

64

1134

11

160

7

5111

51

22

1209

6110

61

11

6010

7109

71

11

6011

8108

81

11

6012

9107

91

11

6013

10106

101

11

6014


Before filling

Reading (m

m)

120 DETER

MIN

ATION

OF W

ATER IN

FILTRATIO

N O

F SOIL (D


eter) (ASTM

D3385-03 &

DIN

-1962 Page-7)

AB

Time

Reading

Water Level

Cum

ulative tim

e, min

Time Interval

(from A), m


B),

mm

Infiltration C

apacity, m

m/m

in

Infiltration C

apacity, m

m/hr

Cum


mm

Project :Pilot R

oad work

Location:Thilafushi

Test- 5N

earby BH-4

13.03.2021C

DE

FG

H

hrm

insec

After filling R

eading (mm

)0

1950

00

00

01

1941

11

160

12

1932

11

160

25

1915

32

0.740

410

18810

53

0.636

7

20183

2010

50.5

3012

30178

3010

50.5

3017

40175

4010

30.3

1820

50171

5010

40.4

2424

60168

6010

30.3

1827


Before filling

Reading (m

m)

195 DETER

MIN

ATION

OF W

ATER IN

FILTRATIO

N O

F SOIL (D


eter) (ASTM

D3385-03 &

DIN

-1962 Page-7)

AB

Time

Reading

Water Level

Cum

ulative tim

e, min

Time Interval

(from A), m


B),

mm

Infiltration C

apacity, m

m/m

in

Infiltration C

apacity, m

m/hr

Cum


mm

APPENDIX- F

SITE PHOTOS

SPT AT BH-1

SPT AT BH-2

SPT AT BH-3

SPT AT BH-4

SPT AT BH-5

SPT AT BH-6

Infiltrometer Test- 1



Field Density Test- 1

3. thilafushi -report revised

Documents