Effect of chitosan bio-polymer stabilization on the mechanical and dynamic characteristics of marl soils
Küçük Resim Yok
Tarih
2023
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The strength of marl soils decreases drastically in the variation of the water content. This has caused such soil to be introduced as problematic soil in geotechnical projects. In the present study, the effect of chitosan biopolymer on the static and dynamic properties of marl soil was investigated. To this end, different amounts of chitosan (up to 0.16%) were mixed with marl soil. Then samples were cured for 7, 28 and 90 days and finally subjected to 0, 1, 4 and 8Freeze-Thaw (F-T) cycles. Unconfined compressive strength (UCS), direct shear, Ultrasonic Pulse Velocity (UPV) and bender element tests were performed on the samples. The results showed that the UCS of the samples stabilized with 0.16% chitosan (as the optimal composition) increased by 227% after 7 days compared to that of unstabilized soil. Moreover, the values of cohesion and internal friction angle for the optimum mixture after 7 days of curing were equal to 38.76 kPa and 21.07 degrees, which was much higher than 21 kPa and 18.26 degrees related to the unstabilized marl soil. Chitosan was able to increase dynamic characteristics such as shear wave velocity and maximum shear modulus of samples by about 51 and 128% after 7 days of curing even after 8F-T cycles compared to those of unstabilized samples. Finally, chitosan exhibited that it can be a suitable alternative to traditional additives as an environmentally-friendly material, as confirmed by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analyses.
Açıklama
Anahtar Kelimeler
Marl soil, Chitosan, Bio-polymer, Stabilization, Bender element, Dynamic characteristics
Kaynak
Transportation Geotechnics
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
42
