Disturbance Response and Control of Shield Construction Adjacent to Bridge and High-rise Buildings

［Objective］The tunnel between Shengchanlu Station and Lihuanglu Station on Jinan Metro Line 2 passes in close proximity to the pile foundations of an elevated bridge and the Eurasia Electronics Building complex. To ensure the smooth implementation of shield tunneling and the safety of existing structures, it is necessary to study the structural response mechanism of the surrounding soil and buildings due to shield tunnel side-passing construction. ［Method］Using finite element simulation, the deformation of adjacent bridge foundation, pile foundation, and ground surface before and after reinforcement during the right and left line shield tunnel crossings is examined. A numerical simulation process is comparatively analyzed with reference to field monitoring data. ［Result & Conclusion］When the construction interval between the left and right lines is within 200 rings, the disturbance effect from dual-line construction may have a superimposed impact, potentially causing excessive deformation of the surrounding soil and building structures, thus jeopardizing the usage safety. Implementing secondary grouting reinforcement within 3 m radius around the tunnel reduces the negative bending moment in the building floor slabs and the columns closest to the tunnel by 45.01%, while reducing the extent and magnitude of ground surface and surrounding building deformation within the design limits, indicating that the secondary grouting can effectively mitigate the stratum disturbance effects caused by shield tunneling. Field monitoring results confirm that soil and pile foundation deformations remain within acceptable limits during the shield tunneling.