Numerical simulations of embankments on soft ground reinforced by Kenaf limited life geosynthetics ( LLGs) using 2D and 3D PLAXIS software | |
| Author | Salisa Chaiyaput |
| Call Number | AIT Thesis no.GE-11-05 |
| Subject(s) | Embankments Siols--Reinforcement Soil-structure interaction |
| Note | A thesis submitted for partial fulfillment of the requirements for the d egree of Master of Engineering in Geotechnical and Earth Resources Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. GE-11-05 |
| Abstract | Geosynthetic materials are widely used to increase stability in the embankment by two functions: tensile reinforcement and as a drainage element. Insertion of Limited Life Geosynthetics (LLGs) beneath the base of an embankment built on soft clay can provide extra lateral restraint and prevent the embankment from failing by rotation or splitting failure. This study investigates woven Kenaf LLGs for reinforcement of embankment on soft clay . Furthermore, the numerical simulation of Kenaf LLGs reinfo rced embankment were performed by PLAXIS 2D and 3D software in order to compare with the observed data in terms of settlement, excess pore water pressures and deformation in reinforcement. Subsequently, two types of LLGs coated and not coated with polyure thane for reduction of water absorption and increase their life time. Ayutthaya sand was used for backfill material which has been widely used for highway embankment construction in Bangkok area. The surface and subsurface settlement rates and settlement magnitudes of the reinforced embankment, and the deformations in the reinforcements as well as the excess pore pressures in the underlying soft ground foundation were recorded and monitored up to 8 months. Moreover, from the measured behavior of the reinfor ced embankment and data from previous researches, the design parameters were back calculated. The rates of settlement from FEM 2D method overestimated the observed settlement s data while the FEM 3D prediction results showed that the predicted settlements were underestimated with observed settlement at 3m and 6m depth due to the three three - dimensional loading and boundary conditions . The results between coated and non - coated LLGs sides were similar in magnitude of excess pore water pressure. Regarding maxim um excess pore - water pressure at the locations of 3m and 6m depth, FEM 2D analyses overestimated the measured field data while the FEM 3D simulation yielded satisfactory agreement with the observed data. The deformations in both coated and non - coated Kenaf LLGs reinforcement have higher values at the middle location of the reinforcements. Consequently, FEM 3D simulation captured the overall behavior of the Kenaf LLGs reinforced embankment with more reasonable agreement between the field observations and the predicted values compared to the FEM 2D simulation Furthermore, it was confirmed that the Kenaf LLGs can be applied for short term embankment reinforcement in order to improve the stability of embankment on soft Bangkok clay |
| Year | 2012 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-11-05 |
| 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) | Bergado, Dennes T.; |
| Examination Committee(s) | Noppadol Phienwej;Pham Huy Giao; |
| Scholarship Donor(s) | Royal Thai Government Fellowship; |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2011 |