B.08.02.2.6 ar123_Att_6_Geotechnical Report for Adjacent Site.pdf

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File No 011LG/2016

CHAPTER I – INTRODUCTION

I.1 INTRODUCTION

The Geotechnical Laboratory Control of the Works and Topography Sarl, (LAGEMOT Sarl), was commissioned by CNAF CONSTRUCTION Sarl LTD Cemalpasa Mah. Bahar Cad 63012Sk Ozdemir AP.N0:5/2 Seyhan Adana Turkey. Phone 0322 457 76 00/45763 61 to make the geotechnical studies within the framework of the construction project of a warehouse at the level of Faya Largeau Airport as well as the topographic levels of the influence that must shelter the work. These geotechnical and topographic studies were made simultaneously from 17 till 20 June 2016.

I.2 BRIEF DESCRIPTION OF THE PROJECT

These are the studies geotechnical and topographic for the Construction of a Warehouse in Ennendi-Ouest Region.

I.3 LOCALISATION, GEOLOGIC FRAME, SEISMICITY

The work to be realized is in the region of Ennedi Ouest, thus in a sedimentary basin where limestone would be put down by lakeside sedimentation by layers or strata stacked in variable thicknesses during the transgression of waters of the sea Paleo-chad in the secondary era.

Chad and particularly Faya area is not an eartquake zone. (zone seismicity is very negligible

I.4 MISSION OF THE LABORATORY

The LAGEMONT received for the mission:

• to proceed to two ( 02 ) polls in the heavy dynamic penetrometer lowered until (6.00

m) from depth each

• to proceed to two ( 02 ) open-air wells lowered(gone down) until 5.00 m from depth each

• to give the stratigraphic cutting of the different formations encountered (constitution of the basement)

• to express an opinion with regard to the nature of grounds crossed according to the various layers encountered

• to express a summary opinion with regard to the eligible constraint of the ground of foundation

• to proceed the topographic studies According to the chart below:

III.1 1 IMPLEMENTED EQUIPMENTS

The Geotechnical Laboratory Control of the Works and Topography gave to this project a compound team of:

For the geotechnical works;

- A Geotechnical Engineer

- A Lab Technician

- An Assistant Lab Technician For The Topography

- A Surveyor Topographer Engineer

- A Prism Carrier

- And a Driver, all have warned specific equipment below;

A heavy dynamic penetrometer, An extractor of stalks, Equipment for the open-air wells, A prize of drill pipe, A total station TC 703 + accessories Other work accessories and consumable products A vehicle 4X4

CHAPTER II – RECOGNITION OF THE GROUND

II.1 METHOD OF RECOGNITION

II.1.1 OPEN AIR POLLS

The open-air polls were realized and gone down to 5m depth each.

Lithological cuttings are in the following chart below:

II.1.2 THE POLLS IN THE HEAVY DYNAMIC PENETROMETER

The polls in the heavy dynamic penetrometer and open-air wells were made on sites and noted according to the chart below:

These essays were realized with the help of a heavy dynamic penetrometer (mass of the mutton 50 kg, height of fall 0.50 m, section of the point 20 cm²). The essay consists in beating stalks in the ground and in determining the tore resistances at the forefront of grounds to various depths.

These resistances are calculated by the application of Dutch formula > > in all 0.20 m of depth. The results are translated in the chart below. The study of the set of the results allows to calculate the minimal constraint Rdmin in the break of the ground. These polls restarted in the influence of the warehouse to construct the building according to the attached sketch in appendix and according to the chart below followed by the graphs of these states of resistance of the ground.

CHART N°1-1: Forced to the break of the following points

The eligible constraint of the ground is obtained by taking the twentieth (1/20) of the constraint in the break and is all considered 1.00 m of depth.

TABLE N°1-2: Eligible constraint of points P1 to P2

II.1.4 GEOLOGICAL AND HYDROGEOLOGICAL DATA OF THE POLLS

III.1.4.1 LITHOLOGY

The campaign of poll allows to distinguish on the whole ground the following trainings (Joined lithological cuttings).

Analysis of results shows that the ground in the place is homogeneous on the depth of the polls because constituted largely by limestone except some first centimetres of laterite in contribution. It is what reflects curves (forced by the ground according to the depths).

III.1.4.2 HYDROGEOLOGY

The level of the groundwater is not reached the period of the ground. Permeability tests were carried out in the zone. 1st and 2nd permeability measurements were recorded very low (lower than 10-8m/s).

V. OPINIONS

Visual identification tests realized on the samples of the ground in position showed that they are essentially formed by limestone.

Further with the analysis of the variations of the curve of the minimal eligible constraints of the ground obtained from the dynamic penetrations, we state that the ground in position is almost homogeneous on the depth of the polls.

To avoid possible differential collapses the foundations must be connected by a system of the rigid stiffeners (stingers). Besides the foundations must be cleaned up well in consideration of the sensibility of grounds in position in the water.

We also recommend to our customer to contact an engineering consulting firm equipped enough on the subject for the good implementation of the present opinion. This arrangement will allow not only a good sizing of the carrying structure of the work but will also allow protecting the stability.

Director General Ing. NGARHITA DJARABEYE Georges

IMPORTANT OBSERVATIONS & RESULTS

1/- The attenberg limits are calculated as : IP 37%; WI = 77% (plastic)

2/- The straight shear test results 0 bar; 12° ; triaxial test (0.5 bar; 3 / 0.2 bar ; 5)

3/- The consolidation index is 1.48. It is a diatomite , accusing index of 63.90 % passing

0.44 mm and a 1.1% passer by 0,80mm and an average specific gravity of 1.02.

4/- The PH in the laboratory at 25° C ( H3O +) is 7.2.

5/- The sulfate contents and the electrical resistivity of the sample is found as;

Sulfate (SO- ²- 4) = 80mg / l; Electrical conductivity = 957.0 us / cm.

6/- The allowable bearing capacity is determined as 1.30kgf/ cm2. The modulus of subgrade reaction is calculated as ks = 1560 t/m3

7/ - The present report cannot be separated from its appendices and thus LAGEMOT disclaims all liability of their misuse which could be made by a communication or partial reproduction without the agreement writes emanating from us.

8/ - In case of changes in the setting-up, the conception and/or the importance of the constructions with regard to the data of the present study which could lead to modifications in the conclusions and the prescriptions of the report, it is consequently asked to the customer to notify to LAGEMOT.

Also new elements highlighted during the execution of the foundations and not having been able to be detected during the operations of gratitude (for example:

Cave of dissolution, located heterogeneousness, diverse pipes etc. …) can make void all or part of the conclusions of the report.

These new elements as well as any important incident arisen during the works (sliding of bank, collapse of the searches, the damages caused to the existing constructions, etc. …) must be immediately indicated to LAGEMOT to allow him to reconsider and to adapt possibly the initially recommended solutions.

LAGEMOT would be responsible of the changes made in his study that if he had given in writing, his agreement on the aforementioned modifications.

9/ - LAGEMOT recommend inevitably to the customer to make proceed, at the time of the opening of the first searches or the realization of the first soles, a visit of construction site by his Technician.

This visit is to verify that the nature of the ground and the depth of the horizon of the foundation are in accordance with the data of the study. It gives place to the establishment of an oral report.

TECHNICAL NOTES ON THE TESTS OF DYNAMIC PENETRATION

The test of dynamic penetration allows evaluating the tore resistance of the layers establishing the basement.

It is executed by means of a device allowing the beating of a steel miniature picket, the diameter of the point of which is upper to the diameters of stalks with the aim of eliminating or reducing the side friction which could practice on the train of stalks.

The value of sharp tore resistance in a given depth is calculated with formula

“DUTCH”.

Where; M = Weight of the mutton H = Height of fall of the mutton P = Weight of the train of stalks e = Recess s = Section of the point n = Number of blows of beating

- The gross values measured during the try are corrected by the application of safety factor to take into account:

• Of the side friction which can be mobilized

• Of the elastic shortening of stalks in the course of beating

• Of the new development in the mutton of beating on the anvil

The device used by LAGEMONT CHAD is a dynamic penetrometer heavy typical "STRASSENTEST" whose characteristics are the following ones:

- Weight of the mutton 50 kg

- Height of fall of the mutton 50 cm

- Section of the point: 15,2 cm2

- Stalks thread by 1,00 m of length

- Weight of the variable picket according to the number of stalks.

- Except opposite specifications, the measures are made for regular sinking of 0.20 m.

The test of dynamic penetration is a limited test that is the indications found during a test concern only a zone very limited around the point of execution.

The Management

The Geotechnical Laboratory Control of the Works and Topography

BP:4541 N’DJAMENA CHAD TEL: 0023566296071

Mail: lagemotsarl@yahoo.fr

PROCESS - VERBAL OF TESTS

Tests made at the request of: CNAF Construction Sarl Ltd

About: Sample of ground coming from ENNENDI-OUEST REGION

(FAYA LARGEAU).

Service: Foundations and Materials

Nature of tests: tests of geotechnical identification

Samples received: 2016

Test date: 27/07/2016

OBSERVATIONS:

This sample was subjected to the tests of geotechnical identification to know: particle size analysis, limits of Atterberg and/or Equivalent of sand.

The main obtained characteristics are gathered on the chart below and the attached index card of identification.

Approval number 033

Diameter of the largest element 0.50mm

Passing in 0,40mm 63.9 %

Passing in 0,08mm 1.1 %

LAGEMOT/CNAF FILE NO: 2016-R-015

Test Sheet No1

DATE

GPS Point

Sampling Point: FAYA LARGEAU E

N

Well No Approval Number

Marker Depth

W % nat WL IP ES

ROOF HRB LG AASHTO RTR

1 33 77 37 A-6-7 0 A3

The Geotechnical Laboratory Control of the Works and Topography BP.4541 Tel: 22533462; Port: 66296071/9994971.Ndjamena CHAD NIF: 9003665W

Poll

PK Rated Distance (m)

STONES GRAVEL SAND SILT CLAY

August 16

PARTTICLE SIZE ANALYSIS

P er ce n ta ge o f th e ac cu m u la te d s ie ve s

The Geotechnical Laboratory Control of the Works and Topography BP.4541 Tel: 22533462; Port: 66296071/9994971.Ndjamena CHAD NIF: 9003665W échantillon

0.00 Rupture Admissible

Latérite en apport 0,2 81,75 4,09

0.25 0,4 54,5 0,6 59,95 0,8 70,85 1 50,4 2,52

1,2 45,36 1,4 35,28 1,6 40,32 1,8 35,28

Calcaire blanchâtre 2 28,08 1,40 2,2 28,08 2,4 32,76 2,6 32,76 2,8 32,76 3 30,59 1,53

3,2 34,96 3,4 34,96 numero

SONDAGES COUPE SONDAGE A CIEL OUVERT

PROJET : CONSTRUCTION ENTREPOT A FAYA LARGEAU 24/06/2016

X:

S1

Y: Z:

Client: CNAF

Méthode:Battage Machine:

Description géologique

Outil:

Prof(m) prof(m)

SPT

Contrainte

3,4 34,96 3,6 39,33 3,8 30,59

4.00 4 16,4 0,82

4,2 12,3 4,4 12,3 4,6 20,5 4,8 24,6 5 19,3 0,97

5,2 15,44 5,4 30,88 5,6 30,88 5,8 30,88

6.00 6 40,15 2,01

Construction Entrepôt CNAF échantillon

0 Rupture Admissible 0,2 65,4 3,27

0.20 Latérite en apport

0,4 32,7 0,6 27,25 0,8 21,8 1 30,24 1,51

1,2 30,24 1,4 25,2 1,6 25,2 1,8 15,12

Calcaire blanchâtre 2 18,72 0,94 2,2 23,4 2,4 23,4 2,6 18,72 2,8 14,01 3 13,11 0,66

3,2 21,85 3,4 17,48

S2

Méthode:Battage Outil: X: Y:

SONDAGES COUPE SONDAGE A CIEL OUVERT

PROJET AETS: CONSTRUCTION ENTREPOT A FAYA LARGEAU

Prof(m) Description géologique

Contrainte

SPT

numero

24/06/2016

Machine:

Client: CNAF

Z:

prof(m)

3,4 17,48 3,6 17,48 3,8 13,11

4.00 4 16,4 0,82

4,2 28,7 4,4 28,7 4,6 32,8 4,8 32,8 5 34,74 1,74

5,2 38,6 5,4 34,74 5,6 30,88 5,8 42,46 6 32,85 1,64

Construction Entrepôt CNAF

FAYA, CLIMATOLOGIC DATA

Average Wind Speed (m/s) for Faya.

Year January February March April May June July August September October November December Average 1969 2,7 2,4 2,1 2,6 3,1 2,4 2,7 1,8 2,5 2,3 3,8 3,2 2,6 1970 3,4 3,9 3,5 3,9 3,3 2,8 1,8 1,9 3,2 4,1 4,2 4,2 3,4 1971 3,9 3,9 3,5 3,1 2,3 2,9 2,3 1,6 3 3,7 3,9 4,1 3,2 1972 3,2 3,5 3,5 2,6 2,5 2,3 2,3 2,3 3 2,9 4,2 4,1 3,0 1973 3,8 3,1 3,4 3,2 3,2 2,8 1,8 2,3 2,9 3 3,8 3,5 3,1 1974 4,3 3,5 2,7 2,4 2,6 2,8 1,9 2,2 2,4 2,8 3,7 4,1 3,0 1975 4,3 3,2 3,2 2,6 2,3 2,7 1,5 1,9 3,2 3,4 3,4 3,3 2,9 1976 3,7 3,5 3,1 2,5 2,2 1,7 1,9 2,8 2,5 2,8 3,3 3,8 2,8 1977 3,7 3,9 4,1 3,3 2,9 3 2,8 1,8 2,8 4 3,7 4,2 3,4 1978 3,2 3,3 3,2 2,9 1,8 2,3 1,8 1,3 2,1 1,8 2,9 3,2 2,5

Rainfall (mm) for Faya Année January February March April May June July August September October November December Cumulative 2005 0 0 0 0 0 0 0 4,2 0 0 0 0 4,2 2006 0 0 0 0 0 0 0 7,5 0 0 0 0 7,5 2007 0 0 0 0 0 0 0 1,9 0 0 0 0 1,9 2008 0 0 0 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 65,1 0 0 0 0 0 65,1 2012 0 0 0 0 0,1 0 0 13,2 0 0 0 0 13,3 2013 0 0 0 0 0 0 0 3,7 0 0 0 0 3,7 2014 0 0 0 0 0 0 0 10,9 0 0 0 0 10,9 2015 0 0 0 0 0 0 0 1 0 0 0 0 1

Sunlight Duration for Faya-Largeau Année January February March April May June July August September October November December Average 1990 8,9 10,8 10,3 10,3 10,3 10,6 10,5 10,1 10,1 10,7 10,2 9,7 10,3 1991 9 10,1 9,8 10,5 10,5 10,6 9,7 9,8 10 9,9 10,1 9,5 10,0 1992 8,8 8,5 3,2 10,7 5,9 10,5 10,4 9,9 6 9,1 9,7 9,3 8,5 1993 8,7 9,8 9,4 9,5 9,8 11,6 11,3 9,6 8,6 9,7 10,5 9,8 10,0 1995 10 10,5 9,1 10,4 10,6 10,6 10,4 9,9 10,5 10,4 10,2 9,6 10,2 1996 10,5 9,8 10,2 10,5 9,8 10,8 10,2 9,6 9,3 10,3 10,3 9,6 10,1 1997 9,1 9,9 9 8,4 9,5 9,1 10,1 9,5 10,3 10,2 10,2 9,5 9,6 1998 9 10,2 8,2 10,1 10,3 10,2 9,5 9,1 7,8 9 10,1 9,6 9,4 1999 9,3 9,8 10,6 10,7 10,5 11,1 9,6 8,8 9,8 10,5 10,2 10 10,2 2000 9,5 9,1 9,9 10,5 9,9 9,7 10,1 9,6 9,4 10,2 10,3 9,7 9,9

Wind Direction in Tchad: May - August ( SE-SSO) , November - May ( N-NE).

SOURCE : Division de la Climatologie (DC)/Direction d'Exploitation et d'Application Météorologique (DEAM) /Direction Générale de la Météorologie Nationale (DGMN)/Aout/2016.