Safety Performance Evaluation of New Tunnels under Existing Bridges
With the continuous development of subway and other rail transit engineering,the structural safety as-sessment of newly built tunnels and adjacent buildings under their mutual influence has become a hot topic of attention.This article evaluates the technical condition of existing bridges based on bridge appearance inspection,and uses finite element numerical simulation analysis to conduct structural safety assessment under the mutual influence of excavation of new tunnel foundation pits and pile foundation intrusion.Research has shown that the horizontal displacement of existing bridge pile foundations is more sensitive to excavation than vertical displace-ment.The maximum horizontal and vertical displacement occur at the top of the pile.When the burial depth of the pile foundation is greater than 15 meters,with the increase of burial depth,the reduction of horizontal displace-ment decreases.When the burial depth is greater than 20 meters,the vertical displacement of the pile foundation is basically not affected by excavation.After the invasion of pile foundation,the safety factor of bearing capacity at the inverted arch position of the newly built tunnel is the smallest,close to 2.51.After the mutual influence be-tween tunnel excavation and pile foundation intrusion,the structural safety performance meets the requirements.
new tunnelexisting bridgessecurity assessmentexcavation of foundation pits
万方数据
维普
