| Author | Sharma Acharya, Shambhu Sagar |
| Call Number | AIT Thesis no. GE-98-29 |
| Subject(s) | Strains and stresses
Soil consolidation test
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of
Master of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | An elasto-plastic stress strain model for describing the behavior of normally to
overconsolidated clays is formulated based on the concepts of Critical State Soil
Mechanics. For the fo1mulation of the model, an experimentally based relationship
for undrained shear strain, a relationship for plastic strain increment ratio is proposed.
A relationship for the variation of IL inside the SBS i.e. Aoc is also proposed. Using
this relationship for the known undrained stress paths, the volumetric strain inside the
SBS can be calculated. The total shear strain is then determined using the proposed
flow rule together with the incremental relationship of Roscoe and Poorooshasb
(1963). But for the case when the undrained stress paths are not known an empirical
relationship between void ratio and stress ratio is proposed based on the experimental
observations. Using this relationship together with the ideas underlying Critical State
Soil Mechanics, an incremental relationship for total volumetric strain is developed
and thus the total shear strain can be calculated using the proposed flow rule and the
empirical relationship of undrained shear strain. The linear relationship of the stress
ratio in e- 1n p plot is assumed to calculate the undrained mean normal stress as the
void ratio corresponding to that stress ratio is known for the conventional drained
path. The model complexity to characterize the soil behavior is controlled through the
use of few input parameters, which can be determined from the Standard laboratory
tests. A detailed assessment of the predictive capabilities of the proposed model is
also presented in comparison to the Pender's model. The proposed model gives good
estimation of the soil behavior especially for the isotropic pre shear consolidated
samples over wide variety of loading conditions. |
| Year | 1999 |
| Type | Thesis |
| School | School of Civil Engineering |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Balasubramaniam, A. S.; |
| Examination Committee(s) | Der Guey, Lin;Seah, T. H.; |
| Scholarship Donor(s) | Government of Japan; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1999 |
