Subway Shield Tunnel Research Articles

Three Dimensional Finite Element Analysis of Subway Shield Tunnel under Exsisting Bridge

One city subway shield tunnel under-passing an existing bridge is analyzed, using the method of the three dimensional finite element analysis to simulate the process of excavating the left and right tunnel to get the data of the subsidence, lateral, stress of the bridge, besides the reaction of the upper structure of the bridge when the shield machine thrusting ahead. The results of the study show that the overall settlement value of the pier is not big, but around piers on both sides, the maximum lateral come to 2.6 mm, and the maximum tension, compression stress of the bridge foundation increased by 1.07MPa and 0.4MPa, and arch structure in construction process stress adverse, it is suggested that we should reinforce the soil around the tunnel treatment to control the bridge foundation of uneven settlement, and at the same time, the process of closely monitor the situation of arch bridge.

Technology of Pile Foundation Underpinning in Shield Tunnel of Xi’an Subway

The technology of shield has been widely used in city subway design, when the shield tunnel encounters a bridge across the river; the key issue is to complete the pile foundation underpinning according to the diverse geological conditions. With an example of subway Shield tunnel project from Xi’an, The paper presents the working procedure and emphases of pile foundation underpinning.Based on the configuration design, both the load beared by one single stake and the distortion of the joists are calculated, the carrying capacity computations indicate that pile foundation underpinning is feasible.

Study on Weak-Disturbance Construction Technology of Casing Bored Pile

Aiming at reducing the influence caused by the pile foundation construction on the existing structures nearby, this paper introduces a new technology of spinning casing bored pile, which is the optimization and combination of different construction technologies. Through the corresponding calculation and analysis, the influence scope and extent of this technology is obtained in this paper. This technology has been successfully applied in the pile foundation engineering of a passenger dedicated line close to subway shield tunnels, it can provide the similar project that needs to consider the influence on the surroundings with reference, and it is worth wide promotion and application.

Quality and safety evaluation system of subway shield tunnel operation and maintenance

Quality and safety evaluation system of subway shield tunnel operation and maintenance

Numerical Simulation on the Surface Subsidence Effect during Shield Tunneling Construction

Against the background of shenyang subway shield tunnel construction, the method of numerical simulation methods are used to analyze the factors of surface subsidence caused by shield construction comprehensively, and the universal finite element program ABAQUS is used to establish mechanical model depended on comprehensive consideration the influence factors of soil warehouses pressure, seepage and groundwater. A dynamic finite element simulation of shield advance process and conclude the surface deformation rule of soil are studied.

Numerical Calculation Method for Prediction of Ground-borne Vibration near Subway Tunnel

This paper describes the development of prediction method for ground-borne vibration from railway tunnels. Field measurement was carried out both in a subway shield tunnel, in the ground and on the ground surface. The generated vibration in the tunnel was calculated by means of the train/track/tunnel interaction model and was compared with the measurement results. On the other hand, wave propagation in the ground was calculated utilizing the empirical model, which was proposed based on the relationship between frequency and material damping coefficient α in order to predict the attenuation in the ground in consideration of frequency characteristics. Numerical calculation using 2-dimensinal FE analysis was also carried out in this research. The comparison between calculated and measured results shows that the prediction method including the model for train/track/tunnel interaction and that for wave propagation is applicable to the prediction of train-induced vibration propagated from railway tunnel.

351491 NUMERICAL CALCULATION METHOD FOR PREDICTION OF GROUND-BORNE VIBRATION NEAR SUBWAY TUNNEL(Infrastructure,Technical Session)

This paper describes the outline of prediction method including the model for train/track/tunnel and that of wave propagation in the ground, which has been developed to predict the subway-induced vibration propagated to the ground surface in consideration of frequency characteristics. Prediction example and verification by field measurement are also carried out at a subway shield tunnel.