scholarly journals IMPLEMENTASI METODOLOGI PERANCANGAN PERKERASAN COAL HAULING ROAD DI STA KM 37+000 – 37+300 BERDASARKAN MANUAL DESAIN PERKERASAN JALAN 2017 MENGGUNAKAN UKURAN AGREGAT TERTENTU

2020 ◽  
Vol 1 (1) ◽  
pp. 137-146
Author(s):  
Geniusman Sidabutar ST IPM ◽  
Desyandi Putraldi ST
Keyword(s):  
Pavement Design ◽  
California Bearing Ratio ◽  
Dump Truck ◽  
Cumulative Number ◽  
Asphaltic Concrete ◽  
Damage Factor ◽  
Design Chart ◽  
The Road ◽  
Class A ◽  
Road Pavement

ABSTRAK Coal hauling road merupakan jalan utama yang dipergunakan untuk mengangkut batubara dari Pit ke Stockpile Port dengan jarak 48 Km menggunakan unit dump truck bermuatan 26 ton hingga 34 ton dengan target produksi 1.000.000 ton pertahun. Unit dump truck yang digunakan masuk ke dalam kategori truck 3 sumbu – sedang, dengan nilai faktor ekivalen beban atau Vehicle Damage Factor (VDF) sesuai dengan tabel dari Manual Perkerasan Jalan 2017. Jumlah lintas harian rata-rata (LHR) semua unit dump truck yang melintas dalam sehari mencapai 270 lintasan sehingga jumlah kumulatif beban gandar standar (CESA) dalam hal ini CESA pangkat 4 sebesar 12.86 x 106 dan CESA pangkat 5 sebesar 17.69 x 106.Secara visual dan kondisi yang ada california bearing ratio (CBR) tanah dasar coal hauling road lebih besar dari 6% maka tidak tidak diperlukan perbaikan tanah dasar. Struktur pengerasan berdasarkan ESA5 masuk ke dalam kategori Bagan Desain 3 dimana berdasarkan Bagan Desain 3, desain perkerasan jalan dilakukan dengan menggunakan pondasi agregat kelas A hingga menggunakan asphaltic concrete wearing course (AC WC). Secara aktual Bagan Desain 3 tidak dapat terpenuhi, sebagai alternatif adalah menggunakan Bagan Desain 5 dimana perkerasan jalan menggunakan 3 lapisan, yaitu lapis pondasi agregat kelas A, kelas B dan Burda (lapis penutup berupa laburan dengan ukuran 20 mm).Penerapan perkerasan jalan dengan mengunakan Bagan Desain 5, khususnya penggunaan agregat A di coal hauling road dipilih menggunakan ukuran 10 mm - 20 mm, 20 mm – 30 mm dan 30 mm – 50 mm sedangkan lapisan burda tidak digunakan. Penggunaan agregat modifikasi ini telah dilakukan di STA KM 37 dengan panjang jalan mencapai 300 meter. Tujuan dari penggunaan agregat modifikasi ini yaitu untuk menjaga traksi roda kendaraan dengan permukaan jalan, mempercepat slippery, mengurangi potensi jalan berdebu dan mengurangi perawatan jalan khususnya penggunaan unit grader. Kata kunci: Coal hauling Road, VDF, LHR, ESA, Manual Desain Perkerasan Jalan, Bagan Desain, Agregat  ABSTRACT Coal hauling road is the main road used to transport coal from the Pit to Stockpile Port with a distance of 48 Km using dump trucks capacity 26 - 34 tons with a production target of 1,000,000 tons per year. The dump truck units used fall into the 3 axes - medium truck category, with the value of the Vehicle Damage Factor (VDF) in accordance with the table from the Road Pavement Manual 2017. The average daily traffic count (LHR) of all dump truck units passing in a day reaches 270 passes so that the cumulative number of standard axle loads (CESA) in this case CESA 4 is 12.86 x 106 and CESA 5 is 17.69 x 106.Visually and the existing condition of California bearing ratio (CBR) of subgrade coal hauling road is greater than 6%, there is no need for subgrade improvement. Based on ESA5 the hardening structure will use Design Chart 3 category. Based on Design Chart 3 the pavement design is carried out using aggregate foundation class A to using asphaltic concrete wearing course (AC WC). Actually Design Chart 3 cannot be fulfilled, as an alternative is to use Design Chart 5 where the pavement uses 3 layers, namely the aggregate foundation layers of class A, class B and Burda (the covering layer is a 20 mm diameter).The application of pavement using Design Chart 5, specifically the use of aggregate A in coal hauling road is chosen using sizes 10 mm - 20 mm, 20 mm - 30 mm and 30 mm - 50 mm while the burda layer is not used. The use of this modified aggregate has been carried out at STA KM 37 with a road length of up to 300 meters. The purpose of using this modified aggregate is to maintain vehicle wheel traction with the road surface, accelerate slippery, reduce the potential for dusty roads and reduce road maintenance, especially the use of grader units. Keywords: Coal hauling Road, VDF, LHR, ESA, Road Pavement Design Manual, Design Chart, Aggregate

scholarly journals Road Pavement Design in One of Oversea Sewage Treatment Plant

2020 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Chengbo Zhang ◽  
Cheng Hu ◽  
Qiaolin Liu ◽  
Zheng Wu
Keyword(s):  
Asphalt Concrete ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Pavement Design ◽  
Design Standard ◽  
The Road ◽  
Road Pavement ◽  
Access Road ◽  
Increase Rate

Three methods are used for Road Pavement Design for access road and internal roads to Dasherkandi Sewage Treatment Plant in Bangladesh, the method, standards and ESA for design of the road are introduced, the issues of design standard for Sewage Treatment Plant, traffic increase rate and seal coat for asphalt concrete of the road are discussed, some of the propose is made to minimize different understanding in execution of the contract, it provides necessary references for similar oversea project in similar country.

scholarly journals ANALISA TEBAL PERKERASAN LENTUR PADA RENCANA PENINGKATAN JALAN RUAS LEGUNDI – PERTIGAAN BUNDER

2019 ◽  
Vol 2 (2) ◽  
pp. 322
Author(s):  
Fandra Andriansyah P ◽  
Sigit Winarto ◽  
Yosef Cahyo Setianto Poernomo ◽  
Agata Iwan Candra
Keyword(s):  
Flexible Pavement ◽  
California Bearing Ratio ◽  
Topographic Map ◽  
The Road ◽  
Final Project ◽  
Class A ◽  
Road Section ◽  
Full Circle ◽  
Pavement Thickness ◽  
General Work

The final project is Analysis of Flexible Pavement Thickness in the Plan for Improvement of Legundi Road Section - Bunder KM.5 + 700 to 13 + 700 STA. 0 + 000 to 4 + 000which comprised the road geometrics, flexible pavement depth completed with the budgeting. A topographic map was employed to make a geometric design. Traffic data of 2018, rainfall data of 2018, and California Bearing Ratio (CBR) data were needed to design the flexible pavement depth. The basic itemized cost of wages, materials, tools, and work itemized cost from General Work BinaMarga of East Java Province Division IV (Surabaya, Gresik, Sidoarjo, Mojokerto, Jombang) were needed to find out the budget. Chosen alternative flexible pavement depth of 10 cm asphalt-concrete MS 744 surface, 20 cm Cement Tread Base (CTB) base, and 50 cm sand-aggregate class A (CBR 70) sub-base.The calculations result in PI 01 Full-Circle bend and PI 02 Full-Circle; at IDR 14.745.341.000.Laporan Akhir ini adalah Analisa Tebal Perkerasan Lentur Pada Rencana Peningkatan Jalan Ruas Legundi – Pertigaan Bunder KM.5+700 s/d 13+700 STA. 0+000 s/d 4+000 yang bertujuan untuk menghitung tebal perkerasan lentur jalan, menghitung geometric jalan dan rencana anggaran biaya proyek. Peta topografi sebagai dasar untuk merencanakan geometric jalan. Data lalu lintas tahun 2018, data curah hujan tahun 2018, data California Bearing Ratio (CBR) untuk merencanakan tebal perkerasan lenturjalan. Data Harga Satuan Dasar upah, bahan, dan alat serta Harga Satuan Pekerjaan dari Departemen Pekerjaan Umum Bina Marga Jatim kelompok IV (Surabaya, Gresik, Sidoarjo, Mojokerto, Jombang) digunakan untuk perhitungan Rencana Anggaran Biaya. Berdasarkan perhitungan didapatkan tebal perkerasan lentur alternative terpilih untuk surface 10cm laston MS 744, base 20 cm Cement Tread Base (CTB) ,serta sub base 50 cm Sirtukelas A (CBR 70). Bentuktikungan PI 01 Full-Circle, dan PI 02 Full-Circle. Biaya yang diperlukanadalahsebesarRp 14.745.341.000,-.

scholarly journals DESAIN TEBAL PERKERASAN TERHADAP VOLUME LALU LINTAS PADA KONDISI TANAH RAWA JALAN LABUHA–TOMORI BACAN KABUPATEN HALMAHERA SELATAN

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Chairul Anwar ◽  
M Taufik Yudha Saputra
Keyword(s):  
Flexible Pavement ◽  
Traffic Volume ◽  
Pavement Design ◽  
Distribution Factor ◽  
The Road ◽  
Road Pavement ◽  
Traffic Lane ◽  
Road Type ◽  
Median Width ◽  
Pavement Thickness

This research was carried out on Jalan Oesman Shah on Labuha-Tomori Road. In determiningflexible pavement thickness, based on the results of analysis and calculation of PavementThickness Design Against Traffic Volume on Swamp Conditions on the Labuha-Tomori RoadSection using the Road Pavement Design Manual Number 02 / M / BM / 2013. Based on theexisting plan, this Labuha-Tomori road section in South Halmahera Regency, North MalukuProvince is an arterial road with 2-lane 2-way road type using the median (2/2 UD), plan width of10 meters, width of existing traffic lane 4, 5 meters, median width of 1 meter, and plannedshoulder width 2.40 m. Based on the results of the analysis of growth rates obtained traffic growthrates of 33.066% over the life of the plan, determining the distribution factor of the lane and thecapacity of the lane of lane 1 and the vehicle in the design lane taken 100%. The equivalent loadfactor can be determined using the value of VDF (Vehicle Damage Factor) according to thesurvey results in the field. The traffic volume plan to determine the CESA4 value = 18,835,021.85= 18.84 million is used for the selection of pavement types while the CESA5 value =33,903,039.33 = 33.90 million is used to determine the type of flexible pavement based on thedesign chart provided in The Road Pavement Design Manual Number 02 / M / BM / 2013, ishighly emphasized in terms of the improvement of subgrade, by looking at the condition of theCBR of the subgrade and CESA5 which will be received by pavement. So if the pavement CBR is5.20% and CESA5 is 33.90 Million, the flexible pavement design is of 2 kinds in the design ofpavement thickness: AC - WC = 4 cm, AC - BC = 15.5 cm, CTB = 15 cm, LPA Class A = 15 cm,Choice of 10 cm and AC - WC = 4 cm, AC - BC = 6 cm, AC BASE = 18 cm, LPA = 30 cm, Choiceof Stock = 10 cm, and Subgrade = 5.20%

Toward Using Tire-Road Contact Stresses in Pavement Design and Analysis

2012 ◽  
Vol 40 (4) ◽  
pp. 246-271 ◽  
Author(s):  
Morris De Beer ◽  
James W. Maina ◽  
Yvette van Rensburg ◽  
Jan M. Greben
Keyword(s):  
Contact Stress ◽  
Contact Stresses ◽  
Road Surface ◽  
Pavement Design ◽  
Tire Model ◽  
Contact Patch ◽  
Circular Shape ◽  
The Road ◽  
Road Pavement ◽  
Vertical Contact

ABSTRACT: Optimization of road pavement design, especially close to the surface of the pavement, requires a more rational approach, which will inevitably include modeling of truck tire-road contact stresses. Various road-surfacing failures have been recorded as evidence that the traditional road pavement engineering tire model idealized by a single uniformly distributed vertical contact stress of circular shape may be inadequate to properly explain and assist in the design against road surface failures. This article therefore discusses the direct measurement of three-dimensional (3D) tire pavement contact stresses using a flatbed sensor system referred to as the “Stress-In-Motion” (SIM) system. The SIM system (or device) consists of multiple conically shaped steel pins, as well as an array of instrumented sensors based on strain gauge technology. The test surface is textured with skid resistance approaching that of a dry asphalt layer. Full-scale truck tires have been tested since the mid-1990s, and results show that 3D tire contact stresses are nonuniform and that the footprint is often not of circular shape. It was found that especially the vertical shape of contact stress distribution changes, mainly as a function of tire loading and associated tire inflation pressures. In overloaded/underinflated cases, vertical contact stresses are the highest toward the edges of the tire contact patch. Higher inflation pressures at lower loads, on the other hand, result in maximum vertical stresses toward the center portion of the tire contact patch. These differences in shape and magnitude need to be incorporated into modern mechanistic-empirical road pavement design tools. Four different idealized tire models were used to represent a single tire type to demonstrate effects of tire modeling on the road pavement response of a typical South African pavement structure incorporating a relatively thin asphalt surfacing. Only applied vertical stress was used for the analyses. It was found that the fatigue life of the road surface layer can be reduced by as much as 94% and strain energy of distortion be increased by a factor of 2.8, depending on the characteristics of the tire model input selected for road pavement design and analysis.

scholarly journals Analisis Lalu Lintas pada Ruas Jalan Lingkar Sicincin-Lubuk Alung Kab.Padang Pariaman untuk Disain Perkerasan

2019 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Dwina Archenita
Keyword(s):  
Pavement Design ◽  
Traffic Load ◽  
Survey Period ◽  
Ring Road ◽  
The Road ◽  
Road Pavement ◽  
Road Section ◽  
On The Road ◽  
Subgrade Strength

Traffic is an important part of road pavement design in addition to subgrade strength. This is because traffic is a burden for the road and is very decisive in the thick planning of each layer of pavement. Thus the calculation of the traffic load should have been carried out before carrying out the design of the pavement. The Sicincin - Lubuk Alung ring road section located in Kab.Padang Pariaman is one of the road sections designed with pavement design. Therefore, a traffic survey was carried out on the road section. Traffic surveys are carried out for three days, two days on weekdays and one day on holidays. Every day the survey time is divided into three times, morning, afternoon and evening at rush hour. The survey in the morning takes place at 07:15 - 08:15 and 08:15 - 09:15 while in the afternoon it takes place at 13:00 - 14:00 and 14:00 - 15:00. Furthermore, for the afternoon survey, it will be held at 16:00 - 17:00 and 17:00 - 18:00. After processing the data, in each survey period the LHR value is obtained for both directions. The LHR value used for pavement design is the largest LHR value of all LHR values obtained.

Improvement of crushed stone – mastic asphalt laying by improving of the conditions of its transportation

2021 ◽  
Vol 2021 ◽  
pp. 139-143
Author(s):  
Denis Shpin ◽  
Keyword(s):  
Asphalt Mixture ◽  
Sharp Decrease ◽  
Modern Technology ◽  
Crushed Stone ◽  
Dump Truck ◽  
The Road ◽  
Mastic Asphalt ◽  
Road Pavement ◽  
Stone Mastic Asphalt ◽  
Urban Conditions

Introduction. Transport times of hot asphalt from its production facility to the road section of laying depends of the distance of the asphalt mixing plants location, also in urban conditions it depends from the intensity of traffic flows, the number of traffic jams on the way of the dump truck.Problems. At the present stage, a sharp decrease of road pavement quality and durability occurs due to an increase of the number of heavy vehicles, an increase of axle loads on the pavement and an increase in the speed limit, due to use of outdated technologies that not correspond to the existing loads by their technical characteristics.Purpose. To analyze the modern technology of crushed stone — mastic asphalt transportation in order to determine the shortcomings in its application.Materials and methods. Analysis of information sources, including foreign sources regarding transportation technologiesResults.Possible consequences of non-observance of the correct transportation technology and their elimination have been determined.Conclusions. During the transportation of crushed stone — mastic asphalt mixture, the temperature and fractional segregation (dissection) of the hot mixture occurs. The main factors that cause it are following: ambient temperature, air humidity, wind speed, bulk filling, transport times, pavement flatness during transportation. To prevent the segregation appearance, it is need to increase the loading rate of the dump truck bulk, using heat-insulating elements during transportation (awnings, metal covers, etc.), also as thorough cleaning of the dump truck bulk surface from any residuals of bituminous and other materials before each loading of crushed stone-mastic asphalt.Keywords: crushed stone-mastic asphalt, temperature segregation, transportation technology.

scholarly journals Geotechnical Evaluation of Road Pavement Failure along the Awotan-Akufo Road, Oyo State Southwestern Nigeria

2019 ◽  
pp. 1-11
Author(s):  
Apanpa, A. Kazeem ◽  
Olayiwola, Hameed ◽  
Anjonrin, Ademola
Keyword(s):  
Moisture Content ◽  
Asphalt Pavement ◽  
Optimum Moisture Content ◽  
Traffic Load ◽  
California Bearing Ratio ◽  
Engineering Properties ◽  
Southwestern Nigeria ◽  
The Road ◽  
Road Pavement ◽  
Natural Moisture Content

In order to access the cause(s) of road failure and proffer preventive measures for the future reconstruction of the Awotan-Akufo road, southwestern Nigeria, the geotechnical engineering properties of the subgrade soil, asphalt pavement thicknesses, drainage and traffic load were evaluated. Soil samples were collected from test pits 1 m deep and at an interval of 50 m and subjected to geotechnical analyses in accordance to AASTHO specification. The grain size distribution revealed that 70% of the entire samples from Awotan-Lifeforte and Adaba failed sections along Akufo road contain amount of fines more than 35% passing through sieve No. 200. The Natural Moisture Content range from 5.73 - 20.21% (Awotan-Lifeforte section) and the entire samples from Adaba failed sections have high natural moisture content ranging from 16.20 - 23.20%. From Atterberg limit test, the Liquid limit of 12 - 56% (Awotan-Lifeforte section) and 26.00 - 40.00% (Adaba Section) were obtained. The Plastic Limit and Plasticity Index of the soils ranges from 8.43 to 49.10% and 1.01 to 7.0% (Awotan-Lifeforte section), and 23.10 - 35.50% and 1.50 - 7.10% (Adaba Section) respectively. Linear shrinkage varies from 0.80 to 9.60% and from 3.10 to 8.80% for Awotan-Lifeforte and Adaba sections, respectively. The Maximum Dry Density of the soils ranged from 1.625 - 1.835 mg/m3 at Optimum Moisture Content of 13.4 - 17.3% (Lifeforte-Awotan section), and MDD of 1.752 - 1.975mg/m3 at Optimum Moisture Content of 13.4-17.3% (Adaba section). The unsoaked California Bearing Ratio are 30.08, 70.14, 39.08%, and the soaked California Bearing Ratio values are 26.17, 11.41, 33.41% (Lifeforte-Awotan section) respectively. At Adaba section of the road, the unsoaked California Bearing Ratio is 3.46, 87.70, 70.14%, and soaked California Bearing Ratio values are 3.42, 32.56, 39.83%. The average asphalt pavement thicknesses around Awotan-Lifeforte section range from 0.60 - 1.10 inches, and that of Adaba section range from 0.57 to 1.46 inches. The study concluded that the road pavement subgrade is silty clay and the geotechnical properties rated below the specifications of the Federal Ministry of Works and Housing at some failed portions. Asphalt pavement thicknesses are grossly inadequate and far below NAPA 2007 recommendation. As such the road cannot withstand the heavily loaded trucks that ply it on regular basis. All aforementioned contributed to the untimely failure of the road.

scholarly journals Perencanaan Perkerasan Kaku Jalan Eksisting Lenangguar – Lunyuk STA 04 – STA 06

2021 ◽  
Vol 17 (1) ◽  
pp. 76-82
Author(s):  
Ummi Khairiyah Br Maha ◽  
Hermansyah Hermansyah ◽  
Dedy Dharmawansyah
Keyword(s):  
Economic Growth ◽  
Pavement Design ◽  
Rigid Pavement ◽  
The Road ◽  
Road Pavement ◽  
Steel Bars ◽  
Concrete Quality

ABSTRACT The existence of roads is essential to support economic growth, agriculture, and other sectors. This is because the road is an essential means of transportation to serve people and goods from one place to another safely, comfortable, and economical. Therefore, it is necessary to plan related to the road pavement. Inappropriate pavement planning is the main cause of road damage. The planning for rigid pavement refers to the often-used guidelines, namely, the Road Pavement Design Manual (Revised on June 2017). The thick design of rigid pavement for the Lenangguar - Lunyuk, using quality of concrete of K400 with a thickness of 19 cm. The sub-foundation uses Lean Mix Concrete with K125 concrete quality and 10 cm of thickness. Dowel 33 mm in diameter uses steel bars 45 cm in length and 40 cm distances. Tie Bar fastener with 16 mm in diameter using a threaded rod, length 70 cm, and distance between rods 75 cm, respectively. ABSTRAKKeberadaan jalan raya sangatlah penting untuk menunjang laju pertumbuhan ekonomi, pertanian dan sektor lainnya. Hal ini dikarenakan jalan merupakan suatu sarana transportasi yang sangat penting untuk melayani pergerakan manusia dan atau barang dari suatu tempat ke tempat lain secara aman, nyaman dan ekonomis, maka dari itu perlu dilakukan perencanaan terkait perkerasan jalan. Perencanaan perkerasan jalan yang tidak sesuai menjadi penyebab utama dari kerusakan jalan. Perencanaan pekerasan kaku ini mengacu pada pedoman yang sering digunakan yaitu, Manual Desain Perkerasan Jalan (Revisi Juni 2017). Dalam rancangan tebal perkerasan kaku jalan lintas Lenangguar – Lunyuk, menggunakan beton K 400 dengan tebal 19 cm. Pondasi bawah menggunakan Lean Mix Concrete dengan mutu beton K 125 dengan tebal 10 cm. Dowel berdiameter 33 mm menggunakan ruji baja polos degan panjang 45 cm dan jarak 40 cm. Pengikat Tie Bar berdiameter 16 mm menggunakan batang ulir, panjang 70 cm dan jarak antar batang 75 cm.

scholarly journals Analisis Produktivitas Alat Berat Pada Pekerjaan Timbunan

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Dian Febrianti ◽  
Zulyaden Zulyaden
Keyword(s):  
Phase Ii ◽  
Calculation Method ◽  
Dump Truck ◽  
Improvement Project ◽  
Ring Road ◽  
The Road ◽  
Class A ◽  
Heavy Equipment ◽  
Class B ◽  
Dump Trucks

Heavy equipment plays an important role in terms of speed and acceleration of work. The road improvement project of Suka Makmue Square - the eastern ring road of capital of phase II, funding from OTSUS budget of Nagan Raya Regency with project cost Rp.3.922.503.000, - road length 2475 m The work followed is preferred heap work, B-class aggregate foundation layers, class A aggregate foundation layers. This research uses heavy equipment dump trucks, motor graders, roller vibrators, water tanker trucks. The purpose of the research is to know the productivity of heavy equipment and to know the time needed by heavy equipment to complete the work. The method used is the calculation method manually using the formula productivity. Based on the calculation of productivity at occupation of accumulation using dump truck production per hour 32,4 m/hour, production per day 259.2 m/day with 11 days, 6 days class B class aggregate work, 4 days class A class aggregate work, motor grader production hourly 128,3 m /hour, production per day 1026,43 m3/day with time 3 day, 2 days class B class aggregate work, 1 day class A class aggregate work, vibrator roller production hourly 64,8 m3/hour, production per day 518,4 m3/day with time 6 days, 3 days class aggregate layer work B , 2 days class A class aggregate work, water tankers truck production per hour 16.2 m3/hour, production per day 129,6 m3/day with 21 days, 11 days class B aggregate work, 8 days class A class aggregate work  Keywords-productivity, heavy equipment, time of work.

scholarly journals Engineering Geophysical Investigation of Road Failure in a Basement Complex Terrain, Southwestern Nigeria

2021 ◽  
pp. 40-51
Author(s):  
Ismaila Abiodun Akinlabi ◽  
Christianah Oluwakemi Adegboyega
Keyword(s):  
California Bearing Ratio ◽  
Electrode Spacing ◽  
Dry Density ◽  
High Plasticity ◽  
Southwestern Nigeria ◽  
The Road ◽  
Road Pavement ◽  
Sandy Clay ◽  
2D Resistivity ◽  
Poor Drainage

Geoelectrical and geotechnical investigations were conducted to determine factors responsible for pavement failure in some segments of Adebayo Alao-Akala road in Ibadan, southwestern Nigeria. The geoelectrical investigation employed Schlumberger vertical electrical sounding conducted at fifteen stations occupied along two failed segments and one stable segment of the road, using station spacing of 25 m and maximum electrode spread of 100 m. 2D electrical resistivity survey was also conducted using the dipole-dipole electrode array with electrode spacing, a, of 1 m and expansion factor, n varied from 1 to 5 m. The VES data were interpreted quantitatively by partial curve matching and computer iteration technique and geoelectric sections were generated while 2D resistivity structures of the subsurface were produced from the inverted 2D resistivity data. The geotechnical investigation involved Grain size distribution, Atterberg limits, Compaction and California Bearing Ratio tests conducted on subsoils collected beneath the segment. The failed segments are underlain by low-resistivity clayey subgrade of resistivity mostly less than 100Ωm while the stable segment overlies sandy clay/clayey sand mixture of relatively higher resistivity, ranging from 200Ωm to 530Ωm. The subsoils of the failed segments comprise high-plasticity sandy clay and sandy gravelly clay while those of the stable segment are medium plasticity sandy clayey gravel. The values of maximum dry density are 1.46 Mg/m3-1.73 Mg/m3, 1.71 Mg/m3-1.86 Mg/m3 and 1.75 Mg/m3-1.82 Mg/m3 respectively, with corresponding optimum moisture content of 7%-8%, 11%-20% and 10%-17% and California bearing ratio under soaked condition for 48 hours of 7%-8%, 17%-20% and 11%-17% respectively. The failure of the road pavement is attributable to the clayey nature of the subgrade, and poor drainage. The stable segment is underlain by excellent-to-good subgrade materials. Ingress of surface water into the clayey subgrade occasioned by poor drainage of run-off resulted in deformation of the road pavement in response to vehicular load.

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