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 resonance rubblization technology can be adopted to reconstruct old concrete pavement and eradicate reflection cracking. This method fractures pavement into fragments quickly and directly casts asphalt on fractures, shortening time cost of reconstruction. Previous studies about this technology mainly concentrated on asphalt-casting methods, and the quality, stiffness, and flatness of reco…
Resonant rubblization technology is often utilized to rehabilitate deteriorated condrete pavements. Vibrations induced by a resonant breaker would produce detrimental effects on lining structures in tunnel during rubblization construction. The in-situ experiments were carried out in Yangjiao Mountain Tunnel in Zheijiang Province, China. First, the characteristics of rubblization-induced vibrati…
Segments floating is often encountered during the large-diameter shield tunneling. Shearing resistance of circumferential joints is of great importance for resisting the tunnel floating. The shearing resistance in terms of circumferential joint dislocation is studied using 3D numerical simulation. The influences of bolt types, gaskets, transmission cushions, and longitude bolt pre-force on the …
The tunnel leakage in sand layer plays an important role in the evolution of the lining stresses and the ground movement. The phenomenon of internal erosion occurs when underground water leaks into the tunnel from the damaged joints or the cracks of the linings. Fines in sand are pulled off by seepage forces and transported throughout the soil matrix into the tunnel. The loss of fines due to se…
Road tunnels, with large cross-section and long distance, bringsabout vital danger to occupants once in fire. The first few minutes in fire isextremely precious for escapers. Meanwhile, professional aid cannot beobtained. Therefore, it is quite necessary to improve the performance in fire toreduce injury and lost to a large extent. However, current research in evacuationbehavior mostly focu…
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…
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…