Research on the Mutual Influence and Control Measures of Shield Tunnel Side-Crossing Bridge Construction in the Peaty Strata
This paper takes the construction of the shield tunnel side-crossing east second ring elevated stone gate overpass between Longqing Road Station and Baiyun Road Station on Kunming Metro Line 5 as the background,and studies the interaction law of the shield tunnel side-crossing bridge construction under different strata stress release rates through numerical simulation.The results show that the vertical unloading effect of the shield tunnel side-crossing bridge construction is greater than the horizontal unloading effect.The bridge piles undergo radial deformation away from the tunnel,resulting in soil loosening between the piles and the tunnel.It is very necessary to apply grouting inside the tunnel for soil reinforcement in practical engineering.The distance between the tunnel and the bridge pile has a significant impact on the construction of shield tunnel side-crossing bridges.When the stress release rate of the stratum is 0.1～0.3,the relative deformation of each section of the pile body is relatively small,and the possibility of pile cracking and damage due to eccentric compression of the pile gene is relatively small.The influence disturbance of the shield tunnel side-crossing bridge construction is mainly distributed within the range of 1～2D(D is the tunnel diameter)around the tunnel.The impact of shield tunnel side-crossing pile on the axial force of the pile is mainly to cause the axial force of the pile above the arch of the shield tunnel to"shrink",and the impact on the pile bending moment is mainly to increase the corresponding pile bending moment in the center area of the side-crossing section of the tunnel.As the stress release rate of the formation increases,the position of the maximum inclination of the shield tunnel side-crossing bridge will change,and the inclination will show a trend of first decreasing and then increasing.The calculation results show that when the stress release rate of the stratum controlled within 0.3,it can meet the requirements of relevant specifications for the allowable value of bridge deformation control.
万方数据
维普
