Deformation response of existing underground utility tunnel structure induced by ground traffic loads
To explore the magnitude,development,and patterns for displacement and deformation of operational underground utility tunnel structures under surface traffic-induced micro-disturbances,a case study is conducted using a soft-soil underground utility tunnel sub-project within the road network of Suqian.A detailed two-dimensional finite element model is developed in forward modeling tool Abaqus to simulate the pavement(including varying vehicular loads),soil strata,utility tunnel structure and its surrounding elements(e.g.,grouting material,backfill,and tunnel base layer).The study inves-tigates the impact of vehicular vibration forces under varying vehicle speeds v,lateral positions x,and load distribution symmetries τ on tunnel deformation behavior through numerical simulations.The re-sults reveal the following:When vehicle loads are symmetrically distributed along the left and right lanes(τ=2),the main structure of the tunnel located directly below the central road divider can exhibit vertical oscillations of several millimeters.However,the peak horizontal dynamic displacement is only in the order of tens of micrometers,indicating a significant disparity between vertical and horizontal de-formation scales.In the case of single-lane traffic(τ=1),where vehicular loads act solely on one side of the tunnel,the structure experiences differential settlement along its lateral direction,causing an in-clination toward the loaded side.As the lateral distance x between the load application area and the mid-span section of the tunnel roof beam increases,the differential displacement between the two sides of the tunnel initially grows and then decreases.Moreover,such loads can induce horizontal dis-placements of approximately 1 mm in the tunnel structure.In general,regardless of single-lane or two-way traffic,an increase in vehicle speed v results in greater maximum vertical displacements at moni-toring points on or near the tunnel structure.The influence of the independent variables on structural deformation ranks in the order of v<x<τ.This study generates a large dataset of deformation histo-ries for operational utility tunnels through finite element simulations,providing a valuable reference for subsequent machine learning model training in related research.
万方数据
维普
