Effect of intrinsic microscopic properties and suction on swell characteristics of compacted expansive clays

Eyo Umo Eyo, Samson Ngambi, Samuel Abbey

Research output: Contribution to journalArticle

1 Citation (Scopus)
4 Downloads (Pure)

Abstract

The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (<2 μm). One-dimensional vertical swell and swell pressure tests were carried out using the standard oedometer to establish the extent of swell. The filter paper technique was adopted to determine the matric suction values for the compacted samples. Pore sizes of the expansive clays were analytically derived and utilized to describe the swell characteristics of the clays. Further microstructural studies were conducted using the scanning electron micrograph (SEM) to better understand the pore and aggregate structure of the samples. Results of analysis of one-dimensional swell under inundation revealed an increase in swelling with increase in the montmorillonite content in the expansive clays. Swell behavioural concepts formulated to describe and predict the volume change characteristics of the clays by accounting for the clay-particle size, pore morphology and suction showed estimates of coefficient of determination exceeding 0.90 hence buttressing the critical significance of the intrinsic properties considered. This approach was tested and validated against a previous model which considered the micro-internal factors influencing swell. Very satisfactory relationships were also achieved between the inherent expansive clay properties such as plasticity index, clay activity and specific surface area.
Original languageEnglish
Pages (from-to)124-131
Number of pages8
JournalTransportation geotechnics
Volume18
Early online date29 Nov 2018
DOIs
Publication statusPublished - Mar 2019

Fingerprint

swell
suction
Clay
clay
agricultural product
examination
swelling
Swelling
effect
Values
Mineralogy
volume change
Clay minerals
montmorillonite
Specific surface area
Pore size
Plasticity
plasticity
mineralogy
Moisture

Bibliographical note

© 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/

Copyright © and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders.

Keywords

  • Expansive clays
  • Particle size analysis
  • Pore size
  • Suction
  • Swell potential

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Transportation
  • Geotechnical Engineering and Engineering Geology

Cite this

Effect of intrinsic microscopic properties and suction on swell characteristics of compacted expansive clays. / Eyo, Eyo Umo; Ngambi, Samson; Abbey, Samuel.

In: Transportation geotechnics, Vol. 18, 03.2019, p. 124-131.

Research output: Contribution to journalArticle

@article{64fed3e007524333a76387e8b7a25d51,
title = "Effect of intrinsic microscopic properties and suction on swell characteristics of compacted expansive clays",
abstract = "The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (<2 μm). One-dimensional vertical swell and swell pressure tests were carried out using the standard oedometer to establish the extent of swell. The filter paper technique was adopted to determine the matric suction values for the compacted samples. Pore sizes of the expansive clays were analytically derived and utilized to describe the swell characteristics of the clays. Further microstructural studies were conducted using the scanning electron micrograph (SEM) to better understand the pore and aggregate structure of the samples. Results of analysis of one-dimensional swell under inundation revealed an increase in swelling with increase in the montmorillonite content in the expansive clays. Swell behavioural concepts formulated to describe and predict the volume change characteristics of the clays by accounting for the clay-particle size, pore morphology and suction showed estimates of coefficient of determination exceeding 0.90 hence buttressing the critical significance of the intrinsic properties considered. This approach was tested and validated against a previous model which considered the micro-internal factors influencing swell. Very satisfactory relationships were also achieved between the inherent expansive clay properties such as plasticity index, clay activity and specific surface area.",
keywords = "Expansive clays, Particle size analysis, Pore size, Suction, Swell potential",
author = "Eyo, {Eyo Umo} and Samson Ngambi and Samuel Abbey",
note = "{\circledC} 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright {\circledC} and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders.",
year = "2019",
month = "3",
doi = "10.1016/j.trgeo.2018.11.007",
language = "English",
volume = "18",
pages = "124--131",
journal = "Transportation geotechnics",

}

TY - JOUR

T1 - Effect of intrinsic microscopic properties and suction on swell characteristics of compacted expansive clays

AU - Eyo, Eyo Umo

AU - Ngambi, Samson

AU - Abbey, Samuel

N1 - © 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright © and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders.

PY - 2019/3

Y1 - 2019/3

N2 - The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (<2 μm). One-dimensional vertical swell and swell pressure tests were carried out using the standard oedometer to establish the extent of swell. The filter paper technique was adopted to determine the matric suction values for the compacted samples. Pore sizes of the expansive clays were analytically derived and utilized to describe the swell characteristics of the clays. Further microstructural studies were conducted using the scanning electron micrograph (SEM) to better understand the pore and aggregate structure of the samples. Results of analysis of one-dimensional swell under inundation revealed an increase in swelling with increase in the montmorillonite content in the expansive clays. Swell behavioural concepts formulated to describe and predict the volume change characteristics of the clays by accounting for the clay-particle size, pore morphology and suction showed estimates of coefficient of determination exceeding 0.90 hence buttressing the critical significance of the intrinsic properties considered. This approach was tested and validated against a previous model which considered the micro-internal factors influencing swell. Very satisfactory relationships were also achieved between the inherent expansive clay properties such as plasticity index, clay activity and specific surface area.

AB - The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (<2 μm). One-dimensional vertical swell and swell pressure tests were carried out using the standard oedometer to establish the extent of swell. The filter paper technique was adopted to determine the matric suction values for the compacted samples. Pore sizes of the expansive clays were analytically derived and utilized to describe the swell characteristics of the clays. Further microstructural studies were conducted using the scanning electron micrograph (SEM) to better understand the pore and aggregate structure of the samples. Results of analysis of one-dimensional swell under inundation revealed an increase in swelling with increase in the montmorillonite content in the expansive clays. Swell behavioural concepts formulated to describe and predict the volume change characteristics of the clays by accounting for the clay-particle size, pore morphology and suction showed estimates of coefficient of determination exceeding 0.90 hence buttressing the critical significance of the intrinsic properties considered. This approach was tested and validated against a previous model which considered the micro-internal factors influencing swell. Very satisfactory relationships were also achieved between the inherent expansive clay properties such as plasticity index, clay activity and specific surface area.

KW - Expansive clays

KW - Particle size analysis

KW - Pore size

KW - Suction

KW - Swell potential

UR - http://www.scopus.com/inward/record.url?scp=85057603988&partnerID=8YFLogxK

U2 - 10.1016/j.trgeo.2018.11.007

DO - 10.1016/j.trgeo.2018.11.007

M3 - Article

VL - 18

SP - 124

EP - 131

JO - Transportation geotechnics

JF - Transportation geotechnics

ER -