| Title |
Effect of Gravel Size on Shear Behavior of Sand with Dispersed Gravels |
| Keywords |
sand;gravel;specimen size;gravel size;maximum deviator stress;모래;자갈;공시체 크기;자갈 크기;최대축차응력 |
| Abstract |
A large number of small particles may surround large gravels which are non-contact and dispersed within the ground. The strength of such soil may be influenced by the mechanical properties of a few coarse gravels. A specimen or gravel size can impact the shear characteristics of sand with dispersed gravels. In this study, the size of gravel and specimen varies and its effect on shear characteristics of a granular soil was evaluated. Five sizes of gravels with 7, 12, 15, 18, and 22 ㎜ were used repeatedly and inserted in the middle of each compacted layer. A specimen consists of five or ten equal layers depending on gravel size, which is 5 ㎝ or 10 ㎝ in diameter and 10 ㎝ or 20 ㎝ in height. An embedded gravel ratio by weight is 3% and constant for all cases with gravel. After consolidation, a series of undrained triaxial compression tests under three confining pressures was performed on sand with dispersed gravels. The maximum deviator stress of a specimen with 10 ㎝ in diameter was at average 30% higher than that with 5 ㎝ in diameter and increased up to 90% for a specimen with gravel. When a gravel size of 7 and 12 ㎜ used, the maximum deviator stress of a specimen with 10 ㎝ in diameter was higher than that of one without gravel, whereas the maximum deviator stress of a specimen with 5 ㎝ was higher or lower than that without gravel. The gravel size and specimen diameter influenced the undrained behavior of sand. The maximum deviator stress of a specimen with gravel either increased or decreased compared to that without gravel, depending on the ratio of gravel size to specimen diameter, 1/5. |