Effect of sample preparation on shear and compression behaviour of clays
21st International Conference on Soil Mechanics and Geotechnical Engineering (ICSMGE 2026), Vienna, Avusturya, 14 - 19 Haziran 2026, ss.471-475, (Tam Metin Bildiri)
- Yayın Türü: Bildiri / Tam Metin Bildiri
- Doi Numarası: 10.53243/icsmge2026-889
- Basıldığı Şehir: Vienna
- Basıldığı Ülke: Avusturya
- Sayfa Sayıları: ss.471-475
- Orta Doğu Teknik Üniversitesi Kuzey Kıbrıs Kampüsü Adresli: Evet
Özet
Beneficial reuse of unsuitable fine-grained
soils in earthworks is often constrained by uncertainty in laboratory-derived
strength and compressibility parameters, particularly when in-situ clays occur
as aggregated peds rather than fully remoulded material. This study
investigates the strength and compression characteristics of specimens prepared
using various sample preparation techniques to determine which method best
replicates in-situ behaviour. In-situ materials were tested under
one-dimensional compression and unconfined compressive strength (UCS) test
conditions to evaluate the structural effects of different clay ped sizes. The soil was either finely ground or chopped
into discrete peds, with both types subsequently compacted using static
uniaxial compaction. X-ray imaging was utilised to examine the pore structure
of the compacted specimens. The results indicate that the compression curves
for ped-compacted specimens are positioned to the right of those for ground
specimens and progressively approach the intrinsic compression line as the ped
size increases. Ped-compacted samples demonstrated greater stiffness up to the
yield point, after which their behaviour converged toward the intrinsic
compression line. UCS tests revealed an inverted-U-shaped trend corresponding
to the different ped sizes, where the smaller and intermediate clay peds
exhibited higher UCS. As the clay ped sizes increased, a decline in strength
occurred, which was also evident through X-ray radiographs exhibiting a higher
pore structure.