Showing 3 results for Triaxial Test
Amir Hamidi, Ali Dehghan,
Volume 9, Issue 2 (9-2015)
Abstract
This paper describes triaxial compression tests conducted to determine the effect of fiber inclusion on stiffness and deformation characteristics of sand-gravel mixtures. Tested soil was a mixture of Babolsar sand from the shores of the Caspian Sea and Karaj River gravel. Portland cement was used as the cementing agent and fibers 12mm in length and 0.023mm in diameter at 0%, 0.5% and 1.0% were added to the mixtures. Triaxial tests were performed on saturated samples in consolidated drained and undrained conditions at confining pressures of 100, 200 and 300 kPa. Deviatoric stress-axial strain, volumetric strain-axial strain, pore pressure-axial strain curves with deformation and stiffness characteristics were investigated. Tests results show that fiber addition increased peak and residual shear strength of the soil. Fiber addition resulted in an increase of the maximum positive and negative volumetric strains. In undrained condition, fiber inclusion caused increase in initial positive pore pressure and final suction. It has also been observed that fibers decreased initial tangent stiffness of the cemented sand-gravel mixture.
Reza Ziaie_moayed, Mehrad Kamalzareh,
Volume 9, Issue 2 (9-2015)
Abstract
Collapsible soils could widely be found in central part of Iran and has caused lots of problems for roads and railroads in that region. Appearance of wide cracks in the collapsible soil near the Tehran-Semnan railroad tracks has caused some worries regarding the safety and performance of the railroad. However, due to the high traffic of the railroad, it is impossible to block the road for remedy. Therefore using injection method was found the most suitable alternative to improve the soil along railroad. The results of field and laboratory tests revealed that the injection of lime has better effects on improving soil characteristics than the other materials. It will significantly decrease the collapsibility potential of soil in saturated condition and will cause an increase in loading capacity of soil. Lime injection was suggested as the most appropriate solution for projects with similar geological condition.
Mehri Sharifi, Maryam Meftahi, Seyed Abolhasan Naeini,
Volume 12, Issue 5 (12-2018)
Abstract
Materials such as waste tire chips were widely used to improve the strength of soil. The objective of this study is to discuss the residual strength or steady-state behavior of sand-waste tire chip mixtures. A series of undrained monotonic triaxial compression tests were conducted on reconstituted saturated specimens of sand and sand-tire chip mixtures with variation in the tire-chip contents from 0 to 4 percentages by dry weight of soil. The specimens are prepared using dry deposition method of preparation. The influence on residual resistance of varying confining pressure (100, 200, and 300 kPa) and sand mixture relative density (40, 65, and 80%) were evaluated. Tests results showed that by increasing the tire chip contents, the residual strength increased and steady-state lines move to the right of log Sus-e diagram. Also, the residual resistance improvement induced by tire chip inclusions was found to be sensitive to the relative density of samples and applied confining pressure.
