Numerical simulations of SDCM and DCM piles under axial and lateral loads and under embankment load : a parametric study | |
| Author | Taweephong Suksawat |
| Call Number | AIT Thesis no.GE-08-09 |
| Subject(s) | Concrete piling--Simulation methods--Thailand--Bangkok Embankments |
| Note | A thesis submitted in partial fulfillment of 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-08-09 |
| Abstract | The new kind of reinforced Deep Cement Mixing (DCM ) pile namely, Stiffened Deep Cement Mixing (SDCM) pile is introduced to mitigate the problems due to the low flexural resistance, quality control problem and unexpected failure of DCM pile. The SDCM pile consists of DCM pile reinforced with concrete core pile. Previously, the full scale pile load test and the full scale embankment loading test were successfully conducted in the field. To continue the study on the behavior of SDCM and DCM piles, the 3D finite element simulations using Plaxis 3D Foundation Software Version 1.6 were conducted in this study. The simulations of full scale pile load test consisted of two categories of testing which are the axial compression and the lateral loading. For DCM C-I and C-2 piles, the clay-cement cohesion, CDCM, and clay-cement modulus, EDCM, were obtained from simulations as 300 kPa and 200 kPa as well as 60,000 kPa and 40,000 kPa, respectively. For the SDCM piles, the simulation results show that increasing length ratio, Lcore/LDCM, increased the bearing capacity whereas the sectional area ratio, Acore/ADCM, has only small effects on the bearing capacity for the axial compression loading. The verified parameters such as the clay-cement cohesion, CDCM, and clay-cement modulus, EDCM, from simulations of axial compression tests were 200 kPa and 30,000 kPa, respectively. On the other hand, increasing the sectional area ratio, Acore/ADCM, significantly influenced the ultimate lateral resistance while the length ratio, Lcore/LDCM, is not significant in the ultimate lateral load capacity when the length of concrete core pile is longer than 3.5 m. In addition, the tensile strength of DCM, TDCM, and concrete core pile, Teare, are very important to the lateral pile resistance. The back-calculation results from simulations of tensile strength were 5000 kPa and 50 kPa for the Tcore and TDCM, respectively. The simulations of the full scale embankment loading indicated similar results to the full scale vertical and lateral pile load tests. By increasing the length ratio, Lcore/LDCM, the surface and subsurface settlements reduced while the area ratio, Acore/ADCM, only slightly reduced the settlements. In addition, the lateral movements of the embankment decreased by increasing both the length ratio, Lcore/LDCM, and the area ratio, Acore/ADCM, Overall, the numerical simulations closely agreed with the field full scale test results and successfully verified the parameters affecting the performances and behavior of SDCM and DCM piles |
| Year | 2009 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-08-09 |
| 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;Park, Kyung-Ho; |
| Scholarship Donor(s) | RTG Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2009 |