scholarly journals Engineering Site Investigation for Foundation Design and Construction in Shale and Sandstone Derived Soils of Okitipupa Area, Southwestern Nigeria

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
FALOWO OLUSOLA OLUMUYIWA
Keyword(s):  
Site Investigation ◽  
Shallow Foundation ◽  
Cone Penetration ◽  
Foundation Design ◽  
Deep Foundation ◽  
Southwestern Nigeria ◽  
Building Foundation ◽  
Allowable Bearing Capacity ◽  
Engineering Standards ◽  
Electrical Soundings

Geotechnical and geo-electrical investigations of Okitipupa has been carried out with the major objectives of establishing the subsoil/geology, evaluate the geotechnical properties and recommend appropriate foundation alternatives for building foundation construction. Seven borings were carried out with hand auger at two cone penetration test locations, and representative samples were collected and analyzed in the laboratory in accordance with relevant geotechnical engineering standards. In addition, six vertical electrical soundings (VES) were also conducted using Schlumberger configuration. The result of VES delineates three major geologic sequence comprising the topsoil/caprock, sand surficial aquifer, and sand intermediate aquifer. The topsoil has resistivity range of 242 – 1503 ohm-m and thickness of 3.4 - 20.9 m composed of clay sand and sand. This layer is capable of supporting shallow foundation such as simple spread, raft of reinforced concrete, with recommended allowable bearing pressure of 100 KN/m2 at depths of 1.0 m and 3.2 m in the northern and southern part of the study area respectively. The estimated settlement are less than 50 mm using foundation width of 0.6 m, but could be reduced by almost 50% if the width is greater than or equal to 2 m. The groundwater level is very deep (>10 m) and may not likely threatens the integrity of the foundation structures. The estimated allowable bearing capacity for strip footing (203 – 980 KN/m2), square footing (608 – 2940 KN/m2) within 1.4 m depth is appropriate. The capacity of driven (deep foundation) circular piles of diameters 400mm, 500mm, and 600mm, the recommended pile capacity varies at depth of 5 m (69 – 124 KN), 10 m (225 – 378 KN), and 15 m (470 – 766 KN), while that of bored circular pile ranges from (36 – 75 KN), 10 m (93 – 180 KN), and 15 m (170 – 317 KN).

scholarly journals Engineering Subsoil Characterization for Shallow Foundation Design in Ode Irele Area of Ondo State, Southwestern Nigeria

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Olumuyiwa O. Falowo ◽  
Michael B. Amodu
Keyword(s):  
Bearing Capacity ◽  
Shallow Foundation ◽  
Soil Conditions ◽  
Cone Penetration ◽  
Foundation Design ◽  
Southwestern Nigeria ◽  
Foundation Soil ◽  
Geotechnical Investigations ◽  
Allowable Bearing Capacity ◽  
Coastal Sand

Integrated geophysical and geotechnical investigations for foundation design have proved to be good veritable tools in effective foundation design and construction. Geophysical and geotechnical methods involving electrical resistivity and cone penetration test have been carried out to investigate the foundation soil conditions of Ode Irele, southwestern Nigeria. Six vertical electrical sounding (VES) were carried out along two traverses; which is complemented by two cone penetration tests with seven trial tests at different subsurface depths. The geotechnical results showed that the soils are sand and silt dominated. All the tested parameters fall within the Nigeria federal ministry of works and housing specification with liquid limit (< 50%), plastic limit (< 30%), plasticity index (< 20%). The geoelectric sections identified maximum of six geoelectric/geologic subsurface layers comprising the topsoil (red sand), weathered layer (made up of coastal sand/white sand), clayey sand (which is the major aquitard in the area), intermediate sand aquifer unit. However the coastal sand layer has moderately high resistivity at shallow depth to sustain foundation load with thickness greater than 2 m. The groundwater level measured from existing borehole records 17.5 m which may not or seriously affect the bases of the foundation footing. Consequently an average allowable bearing capacity of 150 KN/m2 (ultimate bearing capacity of 450 KN/m2) would be appropriate for design of shallow foundation in the area, at a depth not less than 1.6 m in Ode Irele and 0.8 m at Ajagba. The foundation width of 0.6 m would produce minimum bearing settlement less than 25 mm. The appropriate (recommended) ultimate bearing and allowable bearing capacity for strip and square footings at depth levels of 0.6 – 1.2 m vary from 1486 – 1842 KN/m2 and 495 - 614 KN/m2; and 2056 – 2489 KN/m2 and 685 - 830 KN/m2 respectively.

scholarly journals Engineering Site Investigation and Shallow Foundation Design in Ore Area of Ondo State, Nigeria

2020 ◽  
Vol 67 (1) ◽  
pp. 21-33
Author(s):  
O. Falowo Olumuyiwa
Keyword(s):  
Bearing Capacity ◽  
Soil Analysis ◽  
Site Investigation ◽  
Shallow Foundation ◽  
Cone Penetration ◽  
Foundation Design ◽  
Overburden Thickness ◽  
Allowable Bearing Capacity ◽  
Weathered Layer ◽  
Electrical Sounding

AbstractThe study integrates geophysical and geotechnical methods for subsoil evaluation and shallow foundation design. The study involved six vertical electrical sounding and geotechnical investigation involving cone penetration test and laboratory soil analysis. Three major geologic units were delineated; the topsoil, weathered layer and partly weathered/fractured/fresh bedrock. The overburden thickness is in between 15.2–32.9 m. Based on resistivity (16–890 ohm-m) and thickness (12.7–32 m) the weathered layer is competent to distribute structural load to underlying soil/rock. The groundwater level varies from 4.5 to 12.3 m. Therefore an average allowable bearing capacity of 200 kPa is recommended and would be appropriate for design of shallow foundation in the area, at a depth not less than 1.0 m with an expected settlement ranging from 9.03–48.20 mm. The ultimate bearing and allowable bearing capacity for depth levels of 1–3 m vary from 1403–2666 kPa and 468–889 kPa for strip footing while square footing varies in between 1956–3489 kPa and 652–1163 kPa respectively.

scholarly journals Subsoil Engineering Characterization and Foundation Design in Derived Geological Coastal Sands of Ilaje Area of Ondo State, Nigeria

2020 ◽  
pp. 458-468
Keyword(s):  
Bearing Capacity ◽  
Shallow Foundation ◽  
High Resistivity ◽  
Building Structures ◽  
Cone Penetration ◽  
Foundation Design ◽  
Geotechnical Parameters ◽  
Design Alternatives ◽  
Allowable Bearing Capacity ◽  
Ondo State

Engineering subsoil evaluation and foundation design have been undertaken at Ilaje area of Ondo State, Nigeria. The aim of this study was to examine the geo-electrical and geotechnical parameters of the subsoil to sustain building structures and also provide appropriate foundation design alternatives. A total of six VES stations were occupied and complemented with geotechnical analysis of seven soil samples collected at two cone penetration test locations. The result showed that all the determined geotechnical parameters of the subsoil fall within the specification recommended for foundation material by federal ministry of works and housing of Nigeria. The VES showed a predominant (66.67%) HKQ curve type. The upper 5 m is characterized by moderate thickness and high resistivity (average of 450ohm-m) values to sustain structural load. An average allowable bearing capacity of 150 KN/m2 was recommended for design of bases/footings for shallow foundation at a depth not less than 1.0 m. The obtained settlement values are less than 50 mm and within tolerable limit, for foundation width ranging from 0.5 to 3.0 m. However there was drastic reduction in settlement values (below 25mm) when the foundation width was increased to 2 and 3m. The allowable capacity of the driven pile ranges from 64 – 115 KN, 206 – 347 KN, and 418 – 677 KN at 5m, 10 m and 15 m respectively. The allowable bearing capacity for bored piles ranges from 34 – 69 KN, 85 – 165 KN, and 146 – 268 at depth levels of 5 m, 10 m, and 15 m respectively.

CIVIL INFRASTRUCTURE AND BUILDING DESIGN: THE DEVELOPMENT OF GIS DATABASE AND PRODUCT AS DESIGN AID

2016 ◽  
Vol 78 (5) ◽  
Author(s):  
Devagaran Samugavelu ◽  
Abdul Naser Abdul Ghani
Keyword(s):  
Building Design ◽  
Site Investigation ◽  
The State ◽  
Civil Infrastructure ◽  
Foundation Design ◽  
Important Data ◽  
Economical Design ◽  
Building Foundation ◽  
Gis System ◽  
Factual Data

Civil infrastructure as well as building foundation design depends primarily on the availability and accuracy of soil investigation data. The data from site and laboratory are vital for a safe and economical design for any kind of infrastructure or buildings. This paper describes the use of GIS in processing and presenting factual data of site investigation reports in formats that are meaningful to users especially geotechnical designer. The initial effort is carried out for Perak Tengah District in the State of Perak, Malaysia. In this study the site investigation reports are archived in an appropriate manner so it can be quickly retrieved by user at any time. In the second part, the data are stored in GIS system that can be processed and presented into maps describing some basic important data for designer at various depths. Thus, the data are available at any time and the systems will be a meaningful tool for geotechnical designers. 

scholarly journals Criteria for Preliminary Design of an Arched Steel Bridge on Shallow Foundation Under Soil Liquefaction Conditions

2017 ◽  
Vol 11 (1) ◽  
pp. 1170-1190 ◽  
Author(s):  
Isabella Vassilopoulou ◽  
Vasiliki Kaymenaki ◽  
Charis J. Gantes ◽  
George Bouckovalas
Keyword(s):  
Seismic Isolation ◽  
Design Method ◽  
Soil Layer ◽  
Soil Liquefaction ◽  
Shallow Foundation ◽  
Preliminary Design ◽  
Steel Bridge ◽  
Foundation Design ◽  
Deep Foundation ◽  
Liquefiable Soil

Introduction: The research is based on a proposed new foundation design method of bridges on liquefiable soil, consisting of using a shallow foundation and exploiting the liquefiable soil layer as natural seismic isolation, replacing thus the commonly employed deep foundation method. The use of this concept may be hindered by detrimental effects, such as large displacements and rotations that are expected to take place at the foundation of the structure during a strong seismic event, associated with permanent displacements due to the liquefaction phenomenon. Methods: The aim of the current study is to investigate the response of an arched steel bridge with two simply supported spans to displacements and rotations induced by soil liquefaction, delineate the acceptable limits of such ground movements that the bridge can sustain, avoiding the collapse of the superstructure, and define criteria for the preliminary design of the spread footing of the middle pier. To that effect, nonlinear analyses are performed, taking into account geometric and material nonlinearities. Displacements and rotations are imposed at the base of the pier and their amplitude is gradually increased until the first group of structural elements that reach failure is detected. Results and Conclusion: The values of displacements and rotations, for which failure occurs, specify the tolerable design limits. This is a first step towards investigating the feasibility of the above concept for bridges of this type.

scholarly journals Shallow penetrometer tests: theoretical and experimental modelling of penetration and dissipation stages

2020 ◽  
Vol 57 (4) ◽  
pp. 568-579 ◽  
Author(s):  
M.A. Schneider ◽  
S.A. Stanier ◽  
D.J. White ◽  
M.F. Randolph
Keyword(s):  
Back Analysis ◽  
Site Investigation ◽  
Shallow Foundation ◽  
Foundation Design ◽  
Experimental Modelling ◽  
Fine Grained ◽  
Core Samples ◽  
Proof Testing ◽  
A Site ◽  
Multi Phase

Shallow penetrometers are devices that penetrate into and measure the properties of surficial offshore sediments via multi-phase tests involving penetration, dissipation, and rotation stages. In fine-grained soils such as silts and clays, these testing stages yield undrained strength, consolidation, and friction properties relevant to subsea pipeline and shallow foundation design. This paper describes toroid and hemiball devices of the scale for use in box-core samples and associated interpretation methods for the penetration and dissipation stages. The aim of the paper is to provide all tools needed to design and interpret these tests. New large-deformation finite element (LDFE) dissipation solutions are presented, which can be used for back-analysis of the dissipation stage. Results of an extensive laboratory proof testing exercise in kaolin clay, for both the hemiball and toroid penetrometers, are also reported. These results highlight the potential of the two devices to quickly and economically assess strength and consolidation characteristics of fine-grained sediments in box-core samples recovered to the deck of a site investigation vessel.

scholarly journals Daya Dukung dan Penurunan Pondasi pada Pesisir Pantai Timur Kabupaten Bangka

2020 ◽  
Vol 8 (1) ◽  
pp. 38-47
Author(s):  
Ferra Fahriani ◽  
Yayuk Apriyanti
Keyword(s):  
Bearing Capacity ◽  
Field Data ◽  
East Coast ◽  
Shallow Foundation ◽  
Building Construction ◽  
Foundation Settlement ◽  
Structural Failure ◽  
Penetration Test ◽  
Cone Penetration ◽  
Deep Foundation

A Construction of buildings on the beach is needed to provide facilities and infrastructure. An analysis of bearing capacity and foundation settlement for building construction is necessary to avoid structural failure. This study analyzed bearing capacity and foundation settlement on the East coast of Bangka Regency, Bangka Belitung Island Province, including Tikus Beach, Takari Beach and Karang Mas Air Anyir Beach, based on field data from Cone Penetration Test (CPT). Result showed that the level of soil consistency, bearing capacity, and foundation settlement can be analyzed by combining the structural loads for the 1 to 5 floor buildings. Bearing capacity of shallow foundation was calculated using the Meyerhof (1976) method, whereas the deep foundation is using the Meyerhof (1956) method. Settlement of shallow foundation was calculated using the Steinbrenner (1934) method, whereas the deep foundation is using the Vesic (1970) method. This study found the soil consistency levels at three locations had the range from medium to hard level. The analysis of foundation bearing capacity showed that the greater of soil bearing capacity, the smaller of foundation dimensions. The greater the load that must be held by the foundation, the greater the size of the foundation needed to withstand it. The analysis of the settlement showed that the smaller of the soil bearing capacity, the greater of settlement. The greater the load that must be withheld by the foundation, the foundation settlement will greater.

scholarly journals Geophysical and Geotechnical Investigation of Building Failure in A Typical Basement Complex Environment – A Case Study in Ile-Ife, Nigeria

2021 ◽  
Author(s):  
Olaolu Afolabi ◽  
Ayoola Temiloluwa Oladeji ◽  
Babatunde Moruf Salami ◽  
Sadiq Akorede Lawal
Keyword(s):  
Electrical Resistivity ◽  
Basal Layer ◽  
Shallow Foundation ◽  
Cone Penetration ◽  
Basement Complex ◽  
Southwestern Nigeria ◽  
Foundation Soil ◽  
Resistivity Method ◽  
Weathered Layer ◽  
Electrical Resistivity Method

Abstract A building located within the Basement Complex of the ancient town of Ile – Ife, Osun State, Southwestern Nigeria was observed to have failed due to excessive total and differential settlement. The failure was investigated using the electrical resistivity and geotechnical methods The electrical resistivity method involved the 2-D electrical resistivity imaging (ERI) technique using the dipole-dipole array along four traverses of 30 – 60 m in lengths. The geotechnical method involved the cone penetration test (CPT) using the 2.5-ton static penetrometer machine. Quantitative and qualitative analysis of the ERI data were made using the DIPROfWIN software for the pseudo-inversion while the CPT data were interpreted for lithology using standard chart. The results show that the topsoil, about 1.0 m thick, is composed of sandy clay/clay that is characterized by cone resistance (qc) of 0.2 – 2.0 MPa and resistivity of 75 - 200 Ωmm. The underlying clayey weathered layer, which constitute the shallow foundation soil is characterized by thickness of 4 - >10 m, qc of 0.2 – 1.0 MPa, resistivity of 25 - 75 Ωmm and estimated consolidation settlement of 200 – 500 mm. The basal layer is the saprock/fresh bedrock characterized by qc of > 8.0 MPa and resistivity of 100 - 1000 Ωmm. The subsoil is thus characterized by variably thick incompetent clayey weathered layer within which the shallow foundation was placed; hence the excessive total and differential settlements.

Sample size determination in geotechnical site investigation considering spatial variation and correlation

2019 ◽  
Vol 56 (7) ◽  
pp. 992-1002 ◽  
Author(s):  
Yu Wang ◽  
Zheng Guan ◽  
Tengyuan Zhao
Keyword(s):  
Spatial Variation ◽  
Sample Size ◽  
Test Data ◽  
Site Investigation ◽  
Sample Size Determination ◽  
Engineering Practice ◽  
Size Determination ◽  
Penetration Test ◽  
Cone Penetration ◽  
Spatially Varying

Site investigation is a fundamental element in geotechnical engineering practice, but only a small portion of geomaterials is sampled and tested during site investigation. This leads to a question of sample size determination: how many samples are needed to achieve a target level of accuracy for the results inferred from the samples? Sample size determination is a well-known topic in statistics and has many applications in a wide variety of areas. However, conventional statistical methods, which mainly deal with independent data, only have limited applications in geotechnical site investigation because geotechnical data are not independent, but spatially varying and correlated. Existing design codes around the world (e.g., Eurocode 7) only provide conceptual principles on sample size determination. No scientific or quantitative method is available for sample size determination in site investigation considering spatial variation and correlation of geotechnical properties. This study performs an extensive parametric study and develops a statistical chart for sample size determination with consideration of spatial variation and correlation using Bayesian compressive sensing or sampling. Real cone penetration test data and real laboratory test data are used to illustrate application of the proposed statistical chart, and the method is shown to perform well.

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