<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The time-dependent behavior of three gypseous soils was investigated. The soils had gypsum content of 66%, 44%, and 14.8%. The mineralogical and chemical properties of the soils were determined. Two series of tests were performed. In the first, collapsibility characteristics were investigated for a long period (60 days) by conducting single and double oedometer tests. In the second series, the effect of relative density on collapse with time was investigated. The samples were compacted to 40%, 50%, and 60% relative density and then tested. The results of collapse tests showed that the relationship between the strain and logarithm of effective stress has two vertical lines. The first one represents the collapse settlement taking place within 24 h, while the second one represents the long-term collapse. The collapse potential (CP) in both single and double oedometer tests increases when the gypsum content increases from 14.8% to 66% and when the initial void ratio increases.</p>
<p>The CP–logarithm of time relationship for soaked samples prepared at different relative densities under 800 kPa indicated that the CP increased with time for the soil sample compacted at 60% relative density and the increase was higher than those compacted at 40% and 50% relative density. The curves started with a straight line and then a concave downward curve was observed with a high strain. For samples compacted at 40% and 50% relative densities, the curves were interrupted by little soil collapses, while the third curve exhibited smooth relation following the collapse.</p>
</abstract>

The time-dependent behavior of three gypseous soils was investigated. The soils had gypsum content of 66%, 44%, and 14.8%. The mineralogical and chemical properties of the soils were determined. Two series of tests were performed. In the first, collapsibility characteristics were investigated for a long period (60 days) by conducting single and double oedometer tests. In the second series, the effect of relative density on collapse with time was investigated. The samples were compacted to 40%, 50%, and 60% relative density and then tested. The results of collapse tests showed that the relationship between the strain and logarithm of effective stress has two vertical lines. The first one represents the collapse settlement taking place within 24 h, while the second one represents the long-term collapse. The collapse potential (CP) in both single and double oedometer tests increases when the gypsum content increases from 14.8% to 66% and when the initial void ratio increases.
The CP–logarithm of time relationship for soaked samples prepared at different relative densities under 800 kPa indicated that the CP increased with time for the soil sample compacted at 60% relative density and the increase was higher than those compacted at 40% and 50% relative density. The curves started with a straight line and then a concave downward curve was observed with a high strain. For samples compacted at 40% and 50% relative densities, the curves were interrupted by little soil collapses, while the third curve exhibited smooth relation following the collapse.

Effect of Time History on Long-Term Deformation of Gypseous Soils

Building and Construction Engineering Department

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution 4.0 International License.

{"article-title":"Effect of Time History on Long-Term Deformation of Gypseous Soils"}

The time-dependent behavior of three gypseous soils was investigated. The soils had gypsum content of 66%, 44%, and 14.8%. The mineralogical and chemical...

Effect of Time History on Long-Term Deformation of Gypseous Soils

Article Category: Original Study

Published Online: Sep 09, 2022

Page range: 198 - 210

Received: Feb 18, 2021

Accepted: May 08, 2022

DOI: https://doi.org/10.2478/sgem-2022-0011

Keywords
Gypseous soil, creep, collapse, time history, relative density

© 2022 Mohammed Y. Fattah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Effect of Time History on Long-Term Deformation of Gypseous Soils

Article Category: Original Study

Published Online: Sep 09, 2022

Page range: 198 - 210

Received: Feb 18, 2021

Accepted: May 08, 2022

DOI: https://doi.org/10.2478/sgem-2022-0011

KeywordsGypseous soil, creep, collapse, time history, relative density

© 2022 Mohammed Y. Fattah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
Gypseous soil, creep, collapse, time history, relative density