Interactions between geogrid and sand with/without tire chips including sensitivity analyses and simulations | |
| Author | Shehzad, Khurram |
| Call Number | AIT Thesis no.GE-07-03 |
| Subject(s) | Geogrids Rubber--Reinforcement Fillers (Materials)--Testing |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Geotechnical and Geoenvironmental Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. GE-07-03 |
| Abstract | This study is aimed to measure and calculate the interaction coefficient between geogrid and sand as well as geogrid and tire chips-sand mixture using laboratory test numerical simulations. Numerical simulation was imperative for the sensitivity analyses of the laboratory test results to find the important parameters. Two types of material were used as backfill, sand and tire chips-sand mixture. The sand and tire chips mixture were in proportion of 70 and 30 % by weight .The index properties of Ayutthaya and tire chips-sand were measured which were similar to previous research. Polyfelt geogrid was used as geosynthetic reinforcement with tensile strength of 97.48 kN/m from in-air tensile test. Pullout and direct shear tests were done on large scale pullout machine. The shear strength parameters of Ayutthaya sand and tire chips-sand mixture were found to be 29.8◦ friction angle with cohesion of 15.6 kPa for sand and 24.4◦ friction angle with 14.3 kPa cohesion for tire chips-sand mixture. The efficiency of the geogrid obtained were larger when calculated by friction angle and lower when calculated by cohesion. The results reveled that interaction coefficient obtained from direct shear tests was approximately 0.9 for both backfill materials. While 0.7 and 0.6 for the sand and tire chips-sand mix, respectively, were assessed from pullout test. Numerical analyses were also performed by using FE software PLAXIS2D and FD software FLAC2D. The results of the numerical simulation reasonably agreed with the measured laboratory results. As simulation results were similar for the pullout test using both softwares, so simulation of direct shear test was done by using PLAXIS2D software only. Lastly, sensitivity analyses were done for the pullout test by varying the interaction coefficient and axial stiffness of the geogrid. These two important parameters were found to affecting the efficiency of the geogrid reinforcement. |
| Year | 2008 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-07-03 |
| 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) | Park, Kyung-Ho;Pham Huy Giao; |
| Scholarship Donor(s) | Higher Education Commission (HEC), Pakistan; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2008 |