Effects of microencapsulated phase change material characteristics on the thermal performance and mechanical behaviour of silty clay

Microencapsulated phase change material (mPCM) possess an excellent heat storage capacity, which could mitigate temperature fluctuation of soil during freezing/thawing in seasonally frozen regions. Two types of mPCM were investigated using scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infra-red spectroscopy and thermal analysis. Experiments including freezing/thawing tests and unconfined compression tests were conducted to evaluate the behaviour of soil treated with different concentrations of mPCM with butyl stearate and paraffin core material (B-PCM and P-PCM, respectively) during freezing/thawing. The mPCM released and absorbed latent heat, decreasing the temperature variation rate of soil. The unconfined compression strength of silty clay with both types of mPCM displayed diverse trends after freeze-thaw cycles. In contrast to flaky agglomeration in B-PCM-treated soil, the characteristic cementated agglomeration existing in soil aggregates exclusively treated by P-PCM was visually captured using SEM, which formed by the interaction of leaked paraffin in P-PCM and soil due to compaction effort. Furthermore, B-PCM alleviated the strength deterioration of silty clay after freezing/thawing, and the core-to-shell ratio strongly affected the soil strength.

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  • English

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  • Accession Number: 01775840
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 1 2021 9:23AM