Study on disturbance characteristics of sharp curve electric power shield tunnel passing alongside bridge piles
In order to explore the influence of construction of sharp curve electric power shield tunnel on the mechanical properties of pile foundations of adjacent bridge,taking a sharp curve electric power shield tunnel with turning radius of 50 m as an example,the three-dimensional finite element models of sharp curve tunnels passing alongside bridge piles under different horizontal net distance were established.The influence of the horizontal net distance between tunnel and bridge pile on the deformation and stress characteristics of pile foundation was analyzed.The results show that the calculation relative error of the surface settlement value between the numerical simulation and the theoretical value of Peck formula is 4%-19%,which is in the normal range,indicating that the numerical calculation results are reliable.When the horizontal net distance decreases from 3.6 m to 1.2 m,the vertical and transverse deformation values of pile foundations increase,and the growth rates are 143.24%and 55.56%respectively.At the same time,the maximum axial force and maximum bending moment increase by 2.08 times and 3.00 times respectively.The maximum additional bending moment occurs in the pile foundations situated on the inner side of the curve at the buried depth of the tunnel,so the pile foundations bear the most unfavorable stress.Therefore,the pile foundations situated on the inner side of the curve should be well monitored in actual construction.When the net distance is 1.2 m,the differential settlement value and inclination rate of pier column are 0.32 mm and 0.014%respectively,which are less than the allowable specification value.
万方数据
维普
