Effect of jet grouted preceding beams on the performance of diaphragm wall for the MRT orange line project | |
| Author | Mudiyanselage, Rajitha Sachinthaka Subhasinghe |
| Call Number | AIT Thesis no.GE-19-03 |
| Subject(s) | Grouting (Soil stabilization) Diaphragm walls Excavation |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Geotechnical and Earth Resources Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | An evaluation of jet grouted preceding beams on the performance of diaphragm walls was conducted for the MRT Orange Line Project in Bangkok, Thailand. Two parallel jet grouted preceding beams with a thickness of 3 meters were constructed at depths of 10.35 and 26.00 meters below the ground surface as support beams for the diaphragm walls to minimize the movement of the structures during the station construction. A real-time field monitoring program, including the deflection of the diaphragm walls and the ground movement, was conducted at the site. The results of the field monitoring program indicate that the installation of the jet grouted preceding beams effectively reduced the lateral displacement of the diaphragm walls in the top-down deep excavations. Two- and three-dimensional finite element (FE) numerical models were conducted using the Plaxis program to evaluate the design of the jet grouted preceding beams. Soil input parameters used in the 3D FE models were calibrated against the data of the inclinometers installed next to the diaphragm walls at the Orange Line OR-15 station. To simplify the modeling process and to be conservative, 2D FE models were utilized to optimize the design of the jet grouted preceding beams. Preceding beams were evaluated by adjusting the location and the thickness in this study. The results of the numerical modeling analyses indicate that the preceding beams constructed at the current locations provide the least amounts of deflection of the diaphragm walls compared to those at other locations. Furthermore, it was concluded that the thickness of the preceding beams could be optimized with a 16 percent reduction to save material costs and construction time. |
| Year | 2020 |
| 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) | Chao, Kuo-Chieh; |
| Examination Committee(s) | Pham Huy Giao;Wong, Ricky K. N.; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2020 |