Effects of freeze–thaw actions on mechanical properties and constitutive model for diesel-contaminated soil

Abstract

Oil pollution is widespread in frozen regions around the world, and the mechanical properties of clay are highly susceptible to prolonged freeze–thaw cycles and diesel pollution. In order to study the properties of diesel-contaminated clay at the influence of freeze–thaw cycles, the laboratory tests are performed here, based on which the mechanical properties of diesel-contaminated soil under freeze–thaw cycles are studied. Additionally, the effects of freeze–thaw cycles and contents of diesel on the microstructure of clay are studied by scanning electron microscopy. The results show that the shear strength and strength parameters of soil samples decrease with the increase of diesel content and freeze–thaw cycles. Moreover, the scanning electron microscopy (SEM) results show that the freeze–thaw cycle and the increase in diesel content increase the number of large pores and decrease the number of small pores. The soil particles coagulate and form larger pores after the soil sample undergoes freeze–thaw and diesel pollution. The appearance of macropores leads to soil compaction worse and soil strength decrease. Based on the poromechanics, the diesel-contaminated soil is considered as porous material, and a constitutive model with consideration of the influence of freeze–thaw cycles and diesel content is established. The model can model the test results and the main features of diesel-contaminated soil can be duplicated relatively well. Therefore, the study can provide some help in understanding diesel-contaminated engineering under freeze–thaw cycles in cold regions.

Keywords:

• Freeze–thaw cycles
• diesel-contaminated clay
• mechanical properties
• porous medium material
• constitutive model
• microstructure

Acknowledgements

The authors thank the editor and anonymous reviewers for their comments on our article.

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contributions

X.Y.: Conceptualisation, Methodology, Investigation, Validation, Data curation, Writing original draft. E.L.: Conceptualisation, Methodology, Resources, review & editing, Supervision. B.D.: Methodology, Data curation. M.L.: Investigation, Validation.

Code availability

Since this study did not use programming code, this section does not apply.

Consent to participate

Since this study did not recruit any human subjects, this section does not apply.

Consent to publish

Since this study is not attempting to re-publish/publish any third party or author’s previously published material, this section does not apply.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Ethical approval

Since this study did not recruit any human and/or animal subjects, this section does not apply.

Additional information

Funding

This research was supported by National Science Foundation of China [Grant No. 41790431].