An experimental study on mechanical behavior of a calcite cemented gravelly sand

Shakeri, M. R ; Sharif University of Technology | 2018

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  1. Type of Document: Article
  2. DOI: 10.1520/GTJ20170095
  3. Publisher: ASTM International , 2018
  4. Abstract:
  5. In the study presented herein, a simple method for laboratory calcite cementation of a reconstituted gravelly sand was presented. This method was used to prepare cemented gravelly sand specimens, which have similar natural characteristics to alluvial deposit of the city of Tehran. The formation and distribution of calcite bonds, as well as the effectiveness of the presented calcite cementation method in increasing interparticle cohesion, as observed in weakly to moderately cemented soil in Tehran, were evaluated by means of chemical analysis, X-ray diffraction technique, and unconfined compressive strength tests. The cementation technique was used to prepare triaxial specimens with calcite contents ranging from 1.5 to 6 %. Then, a series of monotonic and cyclic undrained triaxial tests was performed to characterize the behavior of calcite-cemented gravelly sand with different calcite contents under different loading conditions. In comparison with the specimens with zero calcite content, the cemented specimens exhibited a distinctly different behavior in terms of static stiffness and strength, cyclic pore pressure generation, and cyclic strength. Results of the monotonic triaxial tests indicated an increased shear strength with an increase in calcite content and confining pressure in the tested soil. Because of the presence of interparticle cohesion, cemented soils behaved less compressive during cyclic loading, and accordingly, the rate of positive pore pressure generation in these specimens was lower during loading with smaller induced plastic deformations. © 2018 by ASTM International
  6. Keywords:
  7. Calcite cementation ; Cyclic pore pressure ; Cyclic strength ratio ; Cyclic triaxial test ; Gravelly sand ; Undrained triaxial test ; Cementing (shafts) ; Chemical analysis ; Compressive strength ; Pore pressure ; Sand ; Shear strength ; Soils ; Cyclic strength ; Cyclic tri-axial tests ; Interparticle cohesion ; Pore-pressure generation ; Unconfined compressive strength ; X-ray diffraction techniques ; Calcite ; Cementation ; Compressibility ; Core analysis ; Experimental study ; Gravel ; Mechanical property ; Triaxial test ; X-ray diffraction ; Iran ; Tehran [Iran]
  8. Source: Geotechnical Testing Journal ; Volume 41, Issue 3 , May , 2018 , Pages 494-507 ; 01496115 (ISSN)
  9. URL: https://www.astm.org/DIGITAL_LIBRARY/JOURNALS/GEOTECH/PAGES/GTJ20170095.htm