Appraisal of soil properties and ground condition for the prediction of embankment behavior | |
| Author | Zamora, Cesar Ryan M. |
| Call Number | AIT Thesis no.GE-02-11 |
| Subject(s) | Embankments Finite element method Soils Analysis |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. GE-02-11 |
| Abstract | Higher prediction accuracies are always desired and because of this, numerous tests are made and models developed. Improvements gained by developments in soil parameter determination are usually checked by conducting behavior predictions using a certain method of analysis and vice versa. However prediction results can not be attributed to either parameter accuracy or to the analysis method but to the relation of both. In this study, required parameter accuracy was quantitatively determined by the limits imposed by the analysis method. Soil prediction using elasto-viscoplastic soil model by Sekiguchi and Ohta(1977) using the FEM method DACSAR was adopted to determine required parameter accuracy. Capability of the adopted analysis method was verified by checking against elastic theory, triaxial tests and actual embankment behavior. From the test using elasticity, it was shown that DACSAR can give reasonably accurate results with appropriate meshing. Upon comparison with triaxial tests, it was verified that soil behavior at compression can be described by the model. This was shown by having outputs with similar trends with measured values. However it was observed that the soil model has an apparent weakness in predicting extension test behavior. Lastly, an embankment simulation was done. From the results of this simulation, it was shown that DACSAR can give acceptable predictions of the general embankment behavior except for predicting lateral displacements and heaving which was attributed to its weakness to simulate extension behavior. Upon verification of the prediction capability, a study on the effects of the main elements of embankment behavior was performed. These elements includes: size of analyzed ground problem discretization, loading rate, the stiff crust layer and the input material properties of the ground. From this step, it can be concluded that problem discretization gives a significant effect on prediction accuracy, the neglect to account the stiff crust layer would lead to serious prediction errors, and lastly focus should be done on determining values for the poisson ratio, preconsolidation pressure and the slope of the swelling line, K, since it was observed that these parameters gave much influence to the predicted results. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-02-11 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Jiro Takemura; |
| Examination Committee(s) | Park, Kyung-Ho;Glawe, Ulrich ; |
| Scholarship Donor(s) | Japanese Government; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2003 |