GEOTECHNICAL INVESTIGATIONS REPORT FORTHE SUPPLY OF RESETTLEMENTHOUSES PROJECT, MS. = ADRIKO JACKSON as BY FOR M/S TECHNICAL MASTERS LTD u REPORT No: STS/QSR/GIR/22/052 SEPTEMBER, 2022DOCUMENT CONTROL Client Technical masters limited : Project ‘Geotechnical investigations report for the supply of resettlement houses Project Report Number STSIQSRIGIRIZ2/052 00 Revision Date Prepared Reviewed ‘Approved for issue - No. 00 ‘8% Sepiember. 2022 | Gloria Agnes ‘Aisha Zaid Eng, Simon Peter Namugabwe KisituEXECUTIVE SUMMARY The Government of Uganda (GoU) with support of the World Bank (IDA) is preparing the Albertine Region Sustainable Development Project. The Albertine Rift Valley is a center for rapid growth which is likely to accelerate with the oil development underway in the region. The two Districts of Buliisa and Hoima are the focus of the project as well as the Town Council of Buliisa. Due to this development, some residents homes are affected by the on-going projects hence a call for resettlement. For this cause, Smat Technical Services conducted a sub-soil survey at the request ofM/S TECHNICAL MASTERS LTD. Sub-soil exploration activities were conducted in accordance with “BS EN 1997- 1:2004 and BS EN 1997-2:2007 “Euro code 7: Geotechnical design- part 2: Ground investigations and testing” The method of exploration/investigation used in the field involved excavating 3No. Trial pits to a maximum depth of 1.3m at the site. Insitu soil resistivity tests and insitu: temperature measurements Were conducted at 1,0m depths in the trial pits. However, standard penetration tests, ‘were not conducted since the underlying soils were found to be coarse grained. Soil samples were retrieved for laboratory determination for classification and strength tests. Classification tests were conducted in accordance withBS EN ISO 17892:12:2019, strength tests were BS 1377: Part 4: 1990 and chemical tests conducted in accordance with BS 1377: Part 7:1990. From in-situ field tests, the average in-situ resistivity of 98 Om and at the time of investigation the site had a temperature ranging from 26°C to 27 From Laboratory testing, classification tests revealed that the sub-surface soils are dark grey fine soils for depthd above 0.3m and light grey soft rock below 0.5m depths characterized with more than 50% of the soil particles retained on sieve No. 200 and non-plastic with liquid limit ranging between 26% to 29%. Compaction testswere not conducted due to the coarse nature of the sub- surface soils, iiiTABLE OF CONTENTS DOCUMENT CONTROL, EXECUTIVE SUMMAR’ LIST OF ACRONYMS.. LIST OF TABLES & FIGURES. nc Vii List of Tables... Nii List of Figures.. Vii CHAPTER ONE: INTRODUCTION..... 1.1 Background... 1.2 Objectives of the investigation 1.2.1 Main Objective 12.2 Specific Objectives... 1.3. Scope of the works... 1.4 Work schedule... CHAPTER TWO: SITE LOCATION AND GENERAL DESCRIPTION ..... 2.1 Site location 4 2.2 Site Geology... 4 2.3. Seismological Aspects..... =5 2.4 Description of the Site CHAPTER THREE: FIELD AND LABORATORY WORKS .. 3.1 Field work... 6 3.1.1 Trial pit locations..... 6 3.1.2 Exploration of the Trial pits. 6 <7 3.1.3 Description of subsurface conditions. 3.1.4 Standard Penetration Test (SPT). 3.1.5 In-Situ Soil Resistivity Tests. -3.1.6 In-Situ temperature measurements, 3.1.7 Soil Sampling. iv3.1.8 — Ground water table measurement 3.2 Laboratory tests... CHAPTER 4: FINDINGS & INTERPRETATION OF RESULTS ..... 4.1 Field test results... 4.1.1 Insitu temperature measurements 4.1.2 Insitu soil resistivity measurements 42 Laboratory test results... 4.2.1 Particle Size Distribution..... 4.2.2 Soil Plasticity... 4.23 Chemical analySis......000sene : 4.3 Interpretation of test results... 43.1 Sub-surface soil types... 4.3.2 Soil volumes and Unit weight relationships... ae) CHAPTER FIVE CONCLUSION, RECCOMENDATIONS & LIMITATIONS ... 5.1 Conclusion... 14 5.2 Recommendations. 5.3 Limitations of the investigation REFERENCES....... APPENDIX It Site Geology eee eee eee ere ee ld, APPENDIX 2- Trial Pit Soil Profiles...... u APPENDIX 3 — Summary of Laboratory test results.mm ASTM BH BS Mpa FOS 1 LIST OF ACRONYMS Meters Millimeters American Standard for Testing and Materials, Bore hole British Standard Mega Pascal’s Disturbed sample Undisturbed sample Kilo Pascal’s Factor of Safety ‘Trial Pit viLIST OF TABLES & FIGURES List of Tables Table 1.1: Work schedule... ‘Table 3.1: Geographical coordinates for each location. ‘Table 3.2:Laboratory tests done and their corresponding standards. Table 3.3: Sample photos showing some of the Laboratory activities.. Table 4.1: Summary of the insitu temperature Table 4.2: Summary of the insitu temperature. ‘Table 4.3: Standard penetration number for the tests done at different depths ‘Table 4.4: MDD/OMC relationship. ‘Table 4.5: 3-Point (4 days soaked) CBR...... ‘Table 4.6: Chemical analysis results. ‘Table 4.7: Unconfined compression strength and soil consistency... ‘Table 4.8: Showing the unit-weight relationships of the soils. List of Figures Figure 1: Red Dot shows the precise location of the site ..... gure 2: Map showing seismologic condition of the project area... Figure 3: Proposed site in Kigaaga village-Buliisa district. Figure 4: Excavation of trial pits........---++++ Figure 5: SPT test being conducted at 1.0m depth... Figure 6:Plasticity chart for the sub-surface soils retrievedINTRODUCTION 1.1 Background Geotechnical Investigations refer to sub-soil surveys conducted to ascertain the ground condition to obtain key parameters used during design of civil engineering structures and facilities. It includes application of the principles of soil mechanics and rock mechanics to the design of foundations, retaining structures, and earth structures. The Government of Uganda (GOU) with support of the World Bank (IDA) is preparing the Albertine Region Sustainable Development Project. The Albertine Rift Valley is a center for rapid growth which is likely to accelerate with the oil development underway in the region. The ‘two Districts of Buliisa and Hoima are the focus of the project as well as the Town Council of Buliisa. Due to this development, some residents homes are affected by the on-going projects hence a call for resettlement. For this cause, at the request of M/S TECHNICAL MASTERS LTD, M/S SMAT Technical Services Limited carried out a subsoil study to ascertain the subsoil profile and determine the subsoil engineering characteristics within thesite proposed for the Supply of replacement houses, M/S. ADRIKO JACKSON. The field activities were conducted on 4"September 2022; the laboratory tests were conducted at SMAT Laboratory located on plot 805, Mawanda road, Kampala. This report forms the key output of the exercise and documents the field and desk activities that \were carried out and the major findings are included in the subsequent chapters. 1.2 Objectives of the investigation 1.2.1 Main Objective To ascertain the subsoil profile and determine the subsoil engineering characteristics within thesite proposed for the Supply of replacement houses 1.2.2 Specific Objectives © To conduct a geotechnical/sub-soil survey on the proposed site ‘© To conduct in-situ field tests and retrieving soil samples © To carry out laboratory tests on the retrieved soil samples ‘* To analyze, assess findings and compile a geotechnical report1.3 Seope of the works ‘The scope of the investigations done was as follows; Excavate 3No. Trial pits to a maximum depth of 1.3m each. Visually describe the soils encountered in each trial pit as the excavation progresses and recording the corresponding subsoil profile. Conducting Standard Penetration tests at 1.0m depths in all the trial pits Collect and handle/preserve disturbed samples from each trial pit at 1.0m depths. Determining the insitu temperature conditions of the site Conducting insitu soil resistivity tests at 1.0m depths in the trial pits excavated. Monitoring and/or measuring the ground water table in each trial pit if encountered. Conducting various laboratory tests on the retrieved soil samples to classify and determine the strength and deformation properties for the underlying soils encountered. Compiling a technical report wBuyyiodax pue sisdyeue sypnsoyy ONLAOUTA oe Qua) ssa Muang ssqs9q peomttIay “(CIGA) s1s93 BUNS Aqwead otjtoods ‘Ayistap ying “(91501 Beapers ‘syrant Rraqrany) sISo1 woHeATSSEID uonexedoid aydumes pue Surdup ofdureg ‘33501 wuoqtoo aunystour femmEN synsay ys01 pray SupzAfeue pu Bupssassy (core Buxdap 07 wrong Tukuse9 ‘sraqumu ge] SuruBtsse ‘sajdures no Sunyos) ‘uondaoar ayduteg SISAL AYOLVAOSVT 07 eaounay ojdures pu sKaains [1os-qns [eo1uyso100¢) ION CTA or SALLIALLV/SMSV.L AOVMOVd MIOA L 9 s (sixpung Suxpnpoxg) seq (2076060 09 2207"60'S) LYPAAN - SOAK SUNK. NIS 9|MPOYDS HOM FTL OTAEL, -sueay Az0yer0gRI Pu Ploy YIoq Aq pornooxo se SHLOM Jo o|Npoys pur sontAHoE pouUP|d aU SMOYS 1° S1GEL STMPOYPS OM HTCHAPTER TWO: SITE LOCATION AND GENERAL DESCRIPTION 2.1 Site location ‘The site is located in Kigumba village. The red dot in the location map in Figure 1 shows an aerial view of the site location, Figure 1:Red Dot shows the precise location of Adriko Jackson site in Kigumba village 2.2 Site Geology The sites area is covered by a 1:1,500,000 solid geology map of Uganda which was compiled and drawn by Geological survey department Entebbe, Uganda in 1961 and published by the Geological Survey of Uganda in 1962 on Series Y 503 Edition 1-USD, Sheet NA-36-14. According to this, the site is mainly constituted by; CAINOZOIC- P1 R, Pleistocene to rece Sediments, alluvium, black soils and moraines. Rift valley sediments. Cainozoic rocks of Uganda composed chiefly of Rift valley sediments, volcanic formations and more recent alluvial overbuirdens, are affected only by epeirogenic movements. The area exhibits deposits of QHa Alluvium, sand, silt, gravel and sand, silt, gritty sandstone of the Neogene Albertine super group. The area also exhibits deposits of the mica schist, graphite schist and quartzites as presented in Appendix 12.3 Seismological Aspects The site lies within zone 1 of the seismic zoning of Uganda, implying there is low risk of Earthquake occurrence at the site. (Seismic Code of Practice for Structural designs; Ugandan National Bureau of Standards, First Edition: June 2003) as presented in Figure 2. Figure 2: Map showing seismologic condition of the project area - 2.4 Description of the Site ‘At the time of the investigations, the site was relatively flat and cleared offplantations and vegetation cover. The proposed site shown in Figure 3 is for a replacement house. Figure 3: Proposed site in Kigumba village-Hoima districtCHAPTER THREE: FIELD AND LABORATORY WORKS 3.1 Field work The field exploration activities were conducted in accordance with “BS EN 1997- 1:2004 and BS EN 1997-2:2007 “Euro code 7: Geotechnical design- part 2: Ground investigations and testing” The method of exploration/investigation used in the field involved excavating3No. Trial pits to a maximum depth of 1.3m at the site. In addition to insitu soil resistivity tests, insitu temperature measurements were conducted at 1.0m intervals in the trial pits. Soil samples were also retrieved at the same depth as shown in the preceding clauses. The subsurface soils were visually studied and described as shown in the soil profiles herein, 3.1.1 Trial pit locations ‘The locations of the investigated points are shown in Table 3.1 below of the geographic co- ordinates of the points which were established using a 51-Channel Acquisition Mini GPS receiver of type L1, C/A code Table 3.1:Geographical coordinates for each location, Exploration No | Maximum depth investigated Co-ordinates (m) TP 1 1.43391 4483N 31. 102432766666 TP 2 rs 1.43394165000002 31.1023719166 TP 3 1433910600001 31.102351916667 3.1.2 Exploration of the Trial pits ‘The trial pits were all investigated to a maximum depth of 1.3m together with the standard penetration tests insitu soil resistivity tests and the insitu temperature measurements. All trial pits were first excavated to a depth of 1.0m where the insitu soil resistivity and insita temperature measurements were done. During sampling, only disturbed samples were retrieved unlike undisturbed samples due to the rocky nature of the soils. Figure 4shows the trial pits being excavated at the proposed site. The soil profiles for the trial pits are shown in Appendix 2(a) Trial pit excavation (b) Cobbles Figure4: Excavation of trial pits 3.1.3 Description of subsurface conditions The excavated trial pits were logged/profiled to present the subsurface soil descriptions, the corresponding soil consistency and conditions that were encountered during the excavation. The trial pit logs of the site are clearly presented in the preceding clauses. 3.14 Standard Penetration Test (SPT) No standard penetration tests (SPT) were carried out. The insitu test was not carried out because of the rocky nature of the site. 3.1.5 In-Situ Soil Resistivity Tests Field measurement of soil resistivity shown in Figure 5, which is the electrical resistance between opposite faces of a unit cube of soil, was used in preference to conductivity as an expression of the electrical character of soil. And it was undertaken using a Wenner four electrode method in accordance to the re-approved ASTM G57-95a designation standard.(a): Insitu resistivity test Figure 5: In-situ soil resistivity test being conducted 3.1.6 In-Situ temperature measurements Insitu temperature measurements were done at 1.0m depths in all the trial pits excavated. 3.1.7 Soil Sampling During sampling, the weather was cloudy throughout the day. Soil samples were retrieved at a depth of 1.0m in each of the trial pits. All the soil samples were well preserved and delivered to SMAT Technical Services Ltd for testing. During sample retrieval all the disturbed samples in all trial pits were collected despite their sandy nature. See Appendices 2for logs showing the description of the 86il samples. 3.1.8 Ground water table measurement All the trial pits after excavation were left to stand for 24 hours in order to observe the ground water level however there was no ground water observed at the site.3.2Laboratory tests Table 3.2 below shows the laboratory tests that were conducted on the disturbed and undisturbed soil samples that were recovered from the trial pits. All tests were conducted from SMAT Technical Services Ltd engineering laboratory located on Plot 805, Mawanda road, Mulago-Kampala. Table 3.3 shown herein show some of the Laboratory work that was done. Test eategory ‘Name of test Standard Test Sample method followed status T. Clas ‘Tests | Natural Moisture Content | BS EN ISO 17892:12 U 2018 Particle Size Distribution | BS EN ISO D (Grading) 17892:12:2018 ‘Aiterberg limits ay rR 17892:12:2019 BS ENISO D Bulk density 17892:12:2019 MDD ; = nT BS 1377: Part 4:1990 Compaction Tests [CBR BS 1377; Part 4:1990 a Soil PH BS 1377:Part 3-1990 o 3 Chemical Te Sulphate content Bs i377 Pan 3.1990 7 ‘Organic matter content 7 Table 3.2: Laboratory tests done and their corresponding standardsTable 3.3: Sample photos showing some of the Laboratory activities @ ‘Soil Pitest ‘@). : Samples soaked in sodium, hexametaphosphate solution @ :Wet sieving Test 10@ fp) Atterberg limits g) + Weighing samples for moisture content 1): Oven drying samples determination | WWCHAPTER 4: FINDINGS &INTERPRETATION OF RESULTS 4.1.1 Insitu temperature measurements ‘The temperature of cach of the trial pits was measured using an infra-red thermometer and recorded. The table below shows the temperature measurements established in the trial pits. Table 4.1: Summary of the insitu temperature at the time of investigations “Trial pit identification ‘Temperature (‘C) TPL 30 TP2 oF TP3 25 4.1.2. Insitu soil resistivity measurements ‘A summary of the insitu soil resistivity test results are presented in the table below Table 4.2: Summary of the insitu temperature at the time of investigations Identification No: Depth(m) eee TP 1 10 212 TR2 10 333 TP3 10 413 4.2 Laboratory test results A summary of all the test results is attached in Appendix 4. 4.2.1 Particle Size Distribution From the particle size distribution test results, the subsurface soils in the trial pits are medium coarse grained soils with more than 50% retained on No 200 test sieve. The soils have a grading modulus ranging from1.24 to 1.55%.4.2.2 Soil Plasticity From the Atterberg limits test results, the soils are generally non plastic with the liquid limit ranging between 26 to 29%, 4.2.3. Chemical analysis Table 4.3 shows the results obtained from the chemical analysis tests on soils ‘Table 4.3: Chemical analysis results for the soil samples tested Soil pH | Organiematter | Chloride content | Sulphate content 7A 0.068 0.025 0.026 70 0.072 0.023 0.025 72 0.068 0.029 0.020 4.3 Interpretation of test results 43.1 Sub-surface soil types From the sub-surface soil logged in Appendix 2, the over burden soils are dark grey fine soils above 3.0m and light brown soft rock together with dark grey rocks to the bottom of all test pits investigated. 4.3.2. Soil volumes and Unit weight relationships The volume relationships determined for the soil samples obtained were the void ratio, porosity and degree of saturation. Porosity is the ratio of volume of voids to the total volume of a soil sample whereas Saturation is the ratio of volume of water present in a given soil sample to the volume of voids in it. These are presented in Table 4.4 p Table 4.4: Showing the unit-weight relationships of the soils at different depths rl Natural | Bulk | Unit | Dry va | Degree of eae Depth | Moisture | Density | Weight | Density eae ee | Porosity | Saturation Xo, | @m) | Content | ys Y gate |e) s 7 (%) | (Mg/m’) | (N/m) | (Mg/m') (%) Ti} 10 | 90 | 1875 | 1839 | 1.720 | 2451 | 04 | 0.298 32 TP2 10 8.2 1,895 18.59 1.751 2.384 0.4 0.265 54 reall 2 | 1876 | 1840 | 1.734 | 2500 | 04 | 0306 | 46 13CHAPTER FIVE CONCLUSION, RECCOMENDATIONS & LIMITATIONS 5.1 Conclusion The proposed site is of geotechnical Category | ‘The site lies within zone 1 of the seismic zoning of Uganda, implying there is a high risk of Earthquake occurrence at the site. (Seismic Code of Practice for Structural designs; Ugandan National Bureau of Standards, First Edition: June 2003), ‘The foundation soils at1.0m are dark grey fine soils above 3.0m and light brown soft rock together with dark grey rocks in all trial pits investigated. No ground water was encountered at the site. Due to the coarse nature the sub-surface soils, undisturbed samples were not retrieved and hence all the tests to be done on the undisturbed samples such as Triaxial shear and odometer tests were not conducted Because of the coarse nature of the soils, more than 50% was retained on sieve No. 200 hence sedimentation tests were not conducted ‘The insitu temperature conditions determined range from 25°C to 30°C ‘The average cath esistvity forthe ste assessed is 3198 iG ay > 145.2 Recommendations © Strip footings are recommended for the foundation design. 5.3 Limitations of the investigation * This report has been prepared for the specific project, purpose, and client stated in the report; ‘© The report may not be adequate for other uses. The use of the recommendations of this report for other projects or purposes or by other parties is not authorized ‘* This investigation was performed using the degree of care and skill at the present time by reputable geo-technical consultant and professional practicing in this or similar localities 15REFERENCES 1. 23 3 BS EN 1997-2:2007 Eurocode 7: Geotechnical design. Ground investigation and testing. Braja, M, D. (2010). Principles of geotechnical engineering - Seventh Edition. British Standards, 1. (1990). BS 1377-9: 1990 Methods of test for Soils for civil engineering purposes — Part 9: In-situ tests. In British Standard (Vol. 3). British Standards Institution. (1990). BS 1377-4:1990 Methods of test for soils for civil engineering purposes. Part 4: Compaction-related tests. British Standard, Part 4. British Standards Institution. (2010). BS 1377-2:1990 Methods of test for soils for civil engineering purposes. Part 2: Classification tests. British Standard, January. British Standards Institution, (2010). BS 1377-9:1990 Methods of test for soils for civil engineering purposes. Part 9: Chemical tests. British Standard, January. Bagonza, S. (2005). Ministry of Works and Transport General Specifications for Roads and Bridge works. 16APPENDIX 1- Site Geology 17Zz emu oy youn (on e1082) ownueooes eon | dno16 ewnsey ueseyaseosoy"0¢ e210u0 epuorquou-owerg vouryeY dno16 nunuy ueseysie0oN” gz 12q1¥ ayn7 149.q]¥ ayD7APPENDIX 2- Trial Pit Soil Profiles 18SPT/TEST BORING LOG FORM sit Revision: | Effective Date: WORKING SHEET NO: - iM o June, 2019 STS-FTF-003 ee Approved by: MD | | | 7 Project: SUPPLY OF RESETTLEMENT HOUSES “Testing Date: |04,09,2022 Client: ‘TECHNICAL MASTERS LTD “Logged by: [GAN KIBAMBURA Method: Continous ght : ase | auger RT ‘Verified by: GAN HOUSE. —_|ADRIKO JACKSON! SPT: Sampler with 63.5kg hammer falling 750mm | uncontined SEU N correcta Compression TRIALPIT DEPTH | Visual Soil (Penetration No, forfield |G, Strength NUMBER (mm) Description (%) | conditions | Consistency | § | Wad (KNim?) | TP 1 | 0 0 | 0 . - - lp 2 10 Grey sands ° 0 ° ac 13 0 ° °APPENDIX 3 -Summary of Laboratory test results 19WWM :SqOM “Wod'sjeuEreWIs|OSBojU ‘epue6in ‘eledwey 2669) x09 “O'd PEON EP (o.LYNS Pun satuormudis padoudde 24) snoyno eodaa dun pun sopsaaig pooruyoa, ay fo toaouddo jf yntn sd20x9 paonpoudas aq rou jpoys woda4 sty ZLZ O€S pbb (9Sz+) :xey “Woo'sjeueEt ‘vOPLS8 ZLL (9SZ+) -GOW ZLL0ES PLY Lue rea es onan yon seepage ma ilar ones omy, 26g pasasddy Seoe voyy™ i 3F8No STALM¥AD jan aguas TvOnWOSL Avie pon om Be a $900 600 | 000 |zL) oa¥e se ret wel er os | zs jes | 19 est oe se 5 96 | oor | on: | oot | oor Nosoyr zoo | soo | cao oc! suse | aanueeaiaauon an wot. ae | up Be a By 05 os a5 49 9 94 68 | 76-96 OL aE OOF | OnE SE Lu oe te se ar es 19 me us| e666 foot |oor om) |zersezoe woVwIuL woo | sco | seo0 || soz fon} PrTs29.05 FOUNDSL IVI :AONIOV ONUISAL 8 Vanni summers sso gaans pe stay lot ands y ALT S4aLs WV WONHDAL SK ALIS NOSNOVE OMGY ‘SESNOH INSIVTTLIASR 0 AHS HL YOU SNOLLVOLLSIANI WH roceaye 20a LUOdaa LSAL AMOLVUOAVT yLyLeeOceL NOILVONNOA UNO ST KLITYNG GSLIWIT SADIAYNAS TVOINHDAL LVINS Yd J J