印尼雅加達黏土參數與深開挖數值分析

Determination of Soil Properties and Numerical Analyses of Deep Excavations Jakarta Clay

李查德(Richard Litanes)

指導教授 ： 楊國鑫

國立臺灣大學/工學院/土木工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102133

摘要

no abstract in chinese (already confirm with NTU library)

關鍵字

none in chinese

並列摘要

Jakarta is the capital city of Indonesia, with more than 10 million inhabitants. Traffic congestion is a major problem in the city for the last 20 years. Therefore, construction of a Mass Rapid Transit (MRT) system to solve this problem is necessary. Due to the limited space in the center of the city, some of the Jakarta MRT stations have to be constructed by deep excavation is crucial and it is essential to control the induced wall deformation and ground surface settlement to ensure the safety of the excavation and adjacent buildings and related studies about deep excavations in Jakarta are rarely available up to now.
This study aims to establish the empirical equations for Jakarta Clay, mainly about the correlation between SPT-N, undrained shear strength (Su), and Young’s modulus (E50). In addition, this study performed finite element analyses using Plaxis 3D to predict the wall deformation in two well-documented cases. By comparing the computed and measured wall deformation, the interpreted soil engineering properties of Jakarta Clay can be verified. Furthermore, the effectiveness of the use of grouted slab for deep excavations in Jakarta is evaluated.
It is essential to consider the time-dependent behavior of Jakarta Clay as it can result in an increment of wall deformation. The existence of a sand lense in the area influences the permeability of the surrounding soil and consequently changes the time-dependent behavior of the clay (i.e., rate of consolidation). Therefore, Terzaghi’s consolidation theory was used to calculate the equivalent hydraulic conductivity (keq) of the clay considering the sand lense. So an equivalent permeability (keq), considering the sand lense is thus defined. Moreover, the equivalent critical permeability (keq,critical) can be determined, where keq,critical is the boundary whether the consolidation should be considered or neglected in the analyses.
TORSA 3 is a one-dimensional beam on the elastic foundation software that deals with excavation cases and the modulus of subgrade reaction (Kh) is used to represent the soil stiffness. This study provides the range of Kh for Jakarta Clay for simplified analyses using the 1-D beam on elastoplastic foundation method.

並列關鍵字

deep excavation ； Jakarta MRT ； soil engineering properties ； wall deformation ； time-dependent behavior ； equivalent critical permeability ； one-dimensional beam on the elastic foundation

參考文獻

Abidin, H. Z., Andreas, H., Gumilar, I., and Gamal, M. (2009). "Land Subsidence and Urban Development in Jakarta (Indonesia)."

Abidin, H. Z., Andreas, H., Djaja, R., Darmawan, D., and Gamal, M. (2008). "Land subsidence characteristics of Jakarta between 1997 and 2005, as estimated using GPS surveys." GPS Solutions, 12(1), 23-32.

Abidin, H. Z., Andreas, H., Gumilar, I., Fukuda, Y., Pohan, Y. E., and Deguchi, T. (2011). "Land subsidence of Jakarta (Indonesia) and its relation with urban development." Natural Hazards, 59(3), 1753.

Agung, M. D., Teng, F., Hsiung, B., and Wahyudi, H. (2020). "Time-dependent behavior of excavations in central Jakarta. "

Aila, W. (2016). "Establishment of Geotechnical Properties and 3D Numerical Models for Deep Excavation in Central Jakarta."National Taiwan University of Science and Technology.