Karst is a common geological condition in engineering construction. In order to study the influence of karst cave and boundary condition on the analysis of free field ground motion in karst area, viscoelastic artificial boundary was studied in free field ground motion analysis of karst region, a three-dimensional finite element model whose dimension is 1000 m × 1000 m × 500 m was set up, ch…
The increasing number of twin-tunnels constructed in river-crossing subway traffic compels the designers to explore its dynamics performance in the excavation progress. The characteristics of particle accelerations of the granular medium in the surroundings are the important factors to reflect the excavation disturbance. In the construction process of the twin-tunnels, the excavation of the sec…
Tunnelling underneath the existing tunnels are very common these days. It is obvious that the under-crossing tunnelling will affect and even damage the existing tunnels. An analytical method is proposed in this paper to better understand the effects of the under-crossing tunnelling on the existing tunnel. The existing tunnel is modeled as a Timoshenko beam lying on a Kerr foundation. The validi…
The additional pile response due to the creep behavior of the soil is disadvantageous to the safety of pile. However, in the current studies for considering the creep behavior of the soft soil, the pile response induced by the long-term settlement of soil is seldom investigated. This paper mainly discusses the pile response during the excavation and operation periods considering the creep behav…
During excavation of NATM tunnel in soft clays, stability problems could arise when the tunnel is too shallow, necessitating special treatment for the surrounding ground such as freezing and jet grouting. However, there is generally no specific rules to help the engineers to determine the critical depth of “shallow” tunnel, which is the dividing line between stably and un…