Tunneling simulation in soft ground using shell elements and grouting layer

Abstract

With the advancement of computer sciences and researches on tunneling simulation in the past, the 3D finite element analysis of tunnel excavation by Tunnel Boring Machines (TBMs) has been extensively used over the last decade. Due to that the complicated construction sequences and relevant loads can be taken into account, complex interaction problems can then be performed. Many simulation techniques have been proposed depending on the assumptions used in the modeling. For modeling the tunnel lining, solid elements are commonly used due to the ratio between the width and thickness of the lining is not large. In addition, most studies focused on the ground deformation, not the lining forces. In the circumstance that the lining forces are essentially observed, the structural elements that directly provide the values are preferred. Therefore, this research attempts to propose the shell elements as tunnel lining together with the grouting layer in the analysis. The analysis results from the proposed method and the conventional one are compared and discussed in terms of ground deformation and lining forces together with the field measurement data. The results reveal that the simulation by the proposed method is sufficient and can reasonably reproduce the soil and lining responses.