Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria

Fidelis Ankwo Abija; Songo Clifford Teme; Ebiegberi Oborie

doi:doi:10.11648/j.jccee.20180306.11

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Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria

Fidelis Ankwo Abija, Songo Clifford Teme, Ebiegberi Oborie

Published in Journal of Civil, Construction and Environmental Engineering (Volume 3, Issue 6)

Received: 14 September 2018 Accepted: 4 October 2018 Published: 25 December 2018

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Abstract

A pre-construction site investigation was carried out in a marshy stream channel and adjoining areas for a proposed building site to characterize the subsurface subgrades and recommend foundation design for which proposed structures include a 1-floor 39.7m x 33.7m hostel, a 20.5m x 10.0m 4-bedroom duplex and a 1- floor 2-bedroom block of flats measuring 28.2m x 11.5m with 1.5 factored design dead + live load data as 2700tons, 655tons and 1270 tons respectively. Field investigations include boring of 10 boreholes to a depth of 10m using auger and sounding of 6 cone penetration tests using a 2.5tons mechanical cone penetrometer. The results indicate a soft clay layer existing from ground surface to a depth varying from 1.0m – 1.1m in the stream channel and 0.60m – 0.70m on the adjoining land. These clays are extra-sensitive to sensitive high compressibility Kaolin clays (CH – OH, MH - OH) with undrained shear strength varying from 42 – 75.0KN/m2, angle of internal friction ranging from 0 - 30 with cone resistance values of 3.0 – 11.0 Kg/cm2. Swell potential ranges from 11.45 – 30.64%, swell index from 0.44 – 0.57, activity from 7.0 – 11.0 and swelling pressure 4.776KPa – 4.890KPa. Below this depth a harder clay layer occurs to a depth of between 4.5m – 5.2m and is proposed to found the structures. Pre-consolidation pressures determined from Oedometer test on undisturbed clay samples retrieved from the centre of the second clay layer varies from 125.0KPa – 162.5KPa and Overconsolidation ratios from 2.75 – 6.40 depicting overconsolidation while water table corrected bearing capacities indicates a favourable fully compensated depth of 1.2m for the building foundations. However excessive total settlement determined using Boussinesq’s average vertical stress ranges from 180.1cm - 211.1cm on adjoining land and 160 -111.9cm on the stream channel under the worst case scenario for the structures necessitating further depth compensation to 2.0m. This yielded a reduction in settlement varying from 8.0% to 9.9% on the stream channel and 16.7% - 18.4% on the adjoining land. Rate of settlement depicts that it will take 6.655 and 28.65 years after construction to achieve 50% and 90% settlement under the worst case scenario. Below these clays are loose to medium density sands of varying grain sizes. Load transfer to these sands through pile foundations was considered using the cone penetrometer as a load test to derive unit toe bearing capacities of piles which embedment depth of 11.0m was recommended.

Published in	Journal of Civil, Construction and Environmental Engineering (Volume 3, Issue 6)
DOI	10.11648/j.jccee.20180306.11
Page(s)	154-170
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2018. Published by Science Publishing Group

Keywords

Building Load, Vertical Stress, Water Table, Bearing Capacities, Pile Tip Capacities, Total Settlement, Rate of Settlement

References

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Fidelis Ankwo Abija, Songo Clifford Teme, Ebiegberi Oborie. (2018). Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. Journal of Civil, Construction and Environmental Engineering, 3(6), 154-170. https://doi.org/10.11648/j.jccee.20180306.11

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ACS Style

Fidelis Ankwo Abija; Songo Clifford Teme; Ebiegberi Oborie. Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. J. Civ. Constr. Environ. Eng. 2018, 3(6), 154-170. doi: 10.11648/j.jccee.20180306.11

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AMA Style

Fidelis Ankwo Abija, Songo Clifford Teme, Ebiegberi Oborie. Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. J Civ Constr Environ Eng. 2018;3(6):154-170. doi: 10.11648/j.jccee.20180306.11

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@article{10.11648/j.jccee.20180306.11,
  author = {Fidelis Ankwo Abija and Songo Clifford Teme and Ebiegberi Oborie},
  title = {Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria},
  journal = {Journal of Civil, Construction and Environmental Engineering},
  volume = {3},
  number = {6},
  pages = {154-170},
  doi = {10.11648/j.jccee.20180306.11},
  url = {https://doi.org/10.11648/j.jccee.20180306.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jccee.20180306.11},
  abstract = {A pre-construction site investigation was carried out in a marshy stream channel and adjoining areas for a proposed building site to characterize the subsurface subgrades and recommend foundation design for which proposed structures include a 1-floor 39.7m x 33.7m hostel, a 20.5m x 10.0m 4-bedroom duplex and a 1- floor 2-bedroom block of flats measuring 28.2m x 11.5m with 1.5 factored design dead + live load data as 2700tons, 655tons and 1270 tons respectively. Field investigations include boring of 10 boreholes to a depth of 10m using auger and sounding of 6 cone penetration tests using a 2.5tons mechanical cone penetrometer. The results indicate a soft clay layer existing from ground surface to a depth varying from 1.0m – 1.1m in the stream channel and 0.60m – 0.70m on the adjoining land. These clays are extra-sensitive to sensitive high compressibility Kaolin clays (CH – OH, MH - OH) with undrained shear strength varying from 42 – 75.0KN/m2, angle of internal friction ranging from 0 - 30 with cone resistance values of 3.0 – 11.0 Kg/cm2. Swell potential ranges from 11.45 – 30.64%, swell index from 0.44 – 0.57, activity from 7.0 – 11.0 and swelling pressure 4.776KPa – 4.890KPa. Below this depth a harder clay layer occurs to a depth of between 4.5m – 5.2m and is proposed to found the structures. Pre-consolidation pressures determined from Oedometer test on undisturbed clay samples retrieved from the centre of the second clay layer varies from 125.0KPa – 162.5KPa and Overconsolidation ratios from 2.75 – 6.40 depicting overconsolidation while water table corrected bearing capacities indicates a favourable fully compensated depth of 1.2m for the building foundations. However excessive total settlement determined using Boussinesq’s average vertical stress ranges from 180.1cm - 211.1cm on adjoining land and 160 -111.9cm on the stream channel under the worst case scenario for the structures necessitating further depth compensation to 2.0m. This yielded a reduction in settlement varying from 8.0% to 9.9% on the stream channel and 16.7% - 18.4% on the adjoining land. Rate of settlement depicts that it will take 6.655 and 28.65 years after construction to achieve 50% and 90% settlement under the worst case scenario. Below these clays are loose to medium density sands of varying grain sizes. Load transfer to these sands through pile foundations was considered using the cone penetrometer as a load test to derive unit toe bearing capacities of piles which embedment depth of 11.0m was recommended.},
 year = {2018}
}

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TY  - JOUR
T1  - Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria
AU  - Fidelis Ankwo Abija
AU  - Songo Clifford Teme
AU  - Ebiegberi Oborie
Y1  - 2018/12/25
PY  - 2018
N1  - https://doi.org/10.11648/j.jccee.20180306.11
DO  - 10.11648/j.jccee.20180306.11
T2  - Journal of Civil, Construction and Environmental Engineering
JF  - Journal of Civil, Construction and Environmental Engineering
JO  - Journal of Civil, Construction and Environmental Engineering
SP  - 154
EP  - 170
PB  - Science Publishing Group
SN  - 2637-3890
UR  - https://doi.org/10.11648/j.jccee.20180306.11
AB  - A pre-construction site investigation was carried out in a marshy stream channel and adjoining areas for a proposed building site to characterize the subsurface subgrades and recommend foundation design for which proposed structures include a 1-floor 39.7m x 33.7m hostel, a 20.5m x 10.0m 4-bedroom duplex and a 1- floor 2-bedroom block of flats measuring 28.2m x 11.5m with 1.5 factored design dead + live load data as 2700tons, 655tons and 1270 tons respectively. Field investigations include boring of 10 boreholes to a depth of 10m using auger and sounding of 6 cone penetration tests using a 2.5tons mechanical cone penetrometer. The results indicate a soft clay layer existing from ground surface to a depth varying from 1.0m – 1.1m in the stream channel and 0.60m – 0.70m on the adjoining land. These clays are extra-sensitive to sensitive high compressibility Kaolin clays (CH – OH, MH - OH) with undrained shear strength varying from 42 – 75.0KN/m2, angle of internal friction ranging from 0 - 30 with cone resistance values of 3.0 – 11.0 Kg/cm2. Swell potential ranges from 11.45 – 30.64%, swell index from 0.44 – 0.57, activity from 7.0 – 11.0 and swelling pressure 4.776KPa – 4.890KPa. Below this depth a harder clay layer occurs to a depth of between 4.5m – 5.2m and is proposed to found the structures. Pre-consolidation pressures determined from Oedometer test on undisturbed clay samples retrieved from the centre of the second clay layer varies from 125.0KPa – 162.5KPa and Overconsolidation ratios from 2.75 – 6.40 depicting overconsolidation while water table corrected bearing capacities indicates a favourable fully compensated depth of 1.2m for the building foundations. However excessive total settlement determined using Boussinesq’s average vertical stress ranges from 180.1cm - 211.1cm on adjoining land and 160 -111.9cm on the stream channel under the worst case scenario for the structures necessitating further depth compensation to 2.0m. This yielded a reduction in settlement varying from 8.0% to 9.9% on the stream channel and 16.7% - 18.4% on the adjoining land. Rate of settlement depicts that it will take 6.655 and 28.65 years after construction to achieve 50% and 90% settlement under the worst case scenario. Below these clays are loose to medium density sands of varying grain sizes. Load transfer to these sands through pile foundations was considered using the cone penetrometer as a load test to derive unit toe bearing capacities of piles which embedment depth of 11.0m was recommended.
VL  - 3
IS  - 6
ER  -

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Author Information

Fidelis Ankwo Abija

Centre for Geomechanics, Energy and Environmental Sustainability, Port Harcourt, Nigeria
Songo Clifford Teme

Department of Geology, Rivers State University, Port Harcourt, Nigeria
Ebiegberi Oborie

Department of Geology, Niger Delta University, Wilberforce Island, Nigeria

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Fidelis Ankwo Abija, Songo Clifford Teme, Ebiegberi Oborie. (2018). Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. Journal of Civil, Construction and Environmental Engineering, 3(6), 154-170. https://doi.org/10.11648/j.jccee.20180306.11

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ACS Style

Fidelis Ankwo Abija; Songo Clifford Teme; Ebiegberi Oborie. Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. J. Civ. Constr. Environ. Eng. 2018, 3(6), 154-170. doi: 10.11648/j.jccee.20180306.11

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AMA Style

Fidelis Ankwo Abija, Songo Clifford Teme, Ebiegberi Oborie. Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria. J Civ Constr Environ Eng. 2018;3(6):154-170. doi: 10.11648/j.jccee.20180306.11

Copy | Download

@article{10.11648/j.jccee.20180306.11,
  author = {Fidelis Ankwo Abija and Songo Clifford Teme and Ebiegberi Oborie},
  title = {Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria},
  journal = {Journal of Civil, Construction and Environmental Engineering},
  volume = {3},
  number = {6},
  pages = {154-170},
  doi = {10.11648/j.jccee.20180306.11},
  url = {https://doi.org/10.11648/j.jccee.20180306.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jccee.20180306.11},
  abstract = {A pre-construction site investigation was carried out in a marshy stream channel and adjoining areas for a proposed building site to characterize the subsurface subgrades and recommend foundation design for which proposed structures include a 1-floor 39.7m x 33.7m hostel, a 20.5m x 10.0m 4-bedroom duplex and a 1- floor 2-bedroom block of flats measuring 28.2m x 11.5m with 1.5 factored design dead + live load data as 2700tons, 655tons and 1270 tons respectively. Field investigations include boring of 10 boreholes to a depth of 10m using auger and sounding of 6 cone penetration tests using a 2.5tons mechanical cone penetrometer. The results indicate a soft clay layer existing from ground surface to a depth varying from 1.0m – 1.1m in the stream channel and 0.60m – 0.70m on the adjoining land. These clays are extra-sensitive to sensitive high compressibility Kaolin clays (CH – OH, MH - OH) with undrained shear strength varying from 42 – 75.0KN/m2, angle of internal friction ranging from 0 - 30 with cone resistance values of 3.0 – 11.0 Kg/cm2. Swell potential ranges from 11.45 – 30.64%, swell index from 0.44 – 0.57, activity from 7.0 – 11.0 and swelling pressure 4.776KPa – 4.890KPa. Below this depth a harder clay layer occurs to a depth of between 4.5m – 5.2m and is proposed to found the structures. Pre-consolidation pressures determined from Oedometer test on undisturbed clay samples retrieved from the centre of the second clay layer varies from 125.0KPa – 162.5KPa and Overconsolidation ratios from 2.75 – 6.40 depicting overconsolidation while water table corrected bearing capacities indicates a favourable fully compensated depth of 1.2m for the building foundations. However excessive total settlement determined using Boussinesq’s average vertical stress ranges from 180.1cm - 211.1cm on adjoining land and 160 -111.9cm on the stream channel under the worst case scenario for the structures necessitating further depth compensation to 2.0m. This yielded a reduction in settlement varying from 8.0% to 9.9% on the stream channel and 16.7% - 18.4% on the adjoining land. Rate of settlement depicts that it will take 6.655 and 28.65 years after construction to achieve 50% and 90% settlement under the worst case scenario. Below these clays are loose to medium density sands of varying grain sizes. Load transfer to these sands through pile foundations was considered using the cone penetrometer as a load test to derive unit toe bearing capacities of piles which embedment depth of 11.0m was recommended.},
 year = {2018}
}

Copy | Download

TY  - JOUR
T1  - Geotechnical Considerations for the Design and Construction of Foundations in a Marshy Stream Channel of Iwochang - Ibeno, Eastern Niger Delta, Nigeria
AU  - Fidelis Ankwo Abija
AU  - Songo Clifford Teme
AU  - Ebiegberi Oborie
Y1  - 2018/12/25
PY  - 2018
N1  - https://doi.org/10.11648/j.jccee.20180306.11
DO  - 10.11648/j.jccee.20180306.11
T2  - Journal of Civil, Construction and Environmental Engineering
JF  - Journal of Civil, Construction and Environmental Engineering
JO  - Journal of Civil, Construction and Environmental Engineering
SP  - 154
EP  - 170
PB  - Science Publishing Group
SN  - 2637-3890
UR  - https://doi.org/10.11648/j.jccee.20180306.11
AB  - A pre-construction site investigation was carried out in a marshy stream channel and adjoining areas for a proposed building site to characterize the subsurface subgrades and recommend foundation design for which proposed structures include a 1-floor 39.7m x 33.7m hostel, a 20.5m x 10.0m 4-bedroom duplex and a 1- floor 2-bedroom block of flats measuring 28.2m x 11.5m with 1.5 factored design dead + live load data as 2700tons, 655tons and 1270 tons respectively. Field investigations include boring of 10 boreholes to a depth of 10m using auger and sounding of 6 cone penetration tests using a 2.5tons mechanical cone penetrometer. The results indicate a soft clay layer existing from ground surface to a depth varying from 1.0m – 1.1m in the stream channel and 0.60m – 0.70m on the adjoining land. These clays are extra-sensitive to sensitive high compressibility Kaolin clays (CH – OH, MH - OH) with undrained shear strength varying from 42 – 75.0KN/m2, angle of internal friction ranging from 0 - 30 with cone resistance values of 3.0 – 11.0 Kg/cm2. Swell potential ranges from 11.45 – 30.64%, swell index from 0.44 – 0.57, activity from 7.0 – 11.0 and swelling pressure 4.776KPa – 4.890KPa. Below this depth a harder clay layer occurs to a depth of between 4.5m – 5.2m and is proposed to found the structures. Pre-consolidation pressures determined from Oedometer test on undisturbed clay samples retrieved from the centre of the second clay layer varies from 125.0KPa – 162.5KPa and Overconsolidation ratios from 2.75 – 6.40 depicting overconsolidation while water table corrected bearing capacities indicates a favourable fully compensated depth of 1.2m for the building foundations. However excessive total settlement determined using Boussinesq’s average vertical stress ranges from 180.1cm - 211.1cm on adjoining land and 160 -111.9cm on the stream channel under the worst case scenario for the structures necessitating further depth compensation to 2.0m. This yielded a reduction in settlement varying from 8.0% to 9.9% on the stream channel and 16.7% - 18.4% on the adjoining land. Rate of settlement depicts that it will take 6.655 and 28.65 years after construction to achieve 50% and 90% settlement under the worst case scenario. Below these clays are loose to medium density sands of varying grain sizes. Load transfer to these sands through pile foundations was considered using the cone penetrometer as a load test to derive unit toe bearing capacities of piles which embedment depth of 11.0m was recommended.
VL  - 3
IS  - 6
ER  -

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