3-Dimensional Numerical Analysis on the TBM Excavation Performance in Rock Mass Considering Joint Characteristics

Abstract

In recent years, urban traffic problems have been increasing rapidly. Therefore, the traffic congestion problem is the biggest problem we must solve in the future, and the solution will be the development of underground roads and underground spaces. As the development of underground spaces in urban areas is needed, the construction of TBM method, which has less vibration and noise than NATM method, is increasing. Therefore, in the face of urban underground spaces, difficult ground, there are many difficulties in the excavation of TBM. The main difficult grounds encountered in TBM excavation are mixed ground, fault zones and soft ground. Recently, due to the development of program technology, there are increasing cases of analyzing TBM through numerical modeling. In this study, the numerical analysis of several cases of jointing from difficult modeling to excavating is performed using the finite element program ABAQUS2019. Modeling recently used BIM (building information modeling) to improve efficiency in infrastructure projects, and imported it into finite element analysis program. The number of TBM construction cases has increased, facing the ground which is difficult to excavate. Therefore, it is time to develop technology to efficiently excavate TBM in unexpected ground conditions. Through this study, The development of more accurate TBM excavation simulation models and the possibility of research to cope with TBM excavation by considering the conditions in difficult grounds were shown. A case study of a homogenous ground is performed in RPM and PR through 3.5m diameter TBM modeling and TBM performance evaluation was performed through dynamic analysis considering joints in Case 3-2 (RPM4.5, PR1.25 mm / rev). The results showed that the TBM thrust force was more affected by the joint gap when comparing the numerical results of the joint direction and the joint gap.