Research And Application Analysis Of Bridge Foundation Deformation Detection Technology

As the development of bridges in our country precedes that of tunnels,and with the continuous development of urban tunnels in recent years,it has become inevitable to build tunnels near existing bridges.Tunnel construction will cause the movement of surrounding soil,lead to settlement and lateral displacement of adjacent bridge pile foundation,and bear the corresponding additional stress,thus affecting the structural safety of the bridge,so it is particularly important to monitor the displacement of bridge foundation in real time and accurately in the process of tunnel construction.Based on the first stage A section of Shenzhen Coastal Avenue,this paper analyses the influence of tunnel construction on adjacent bridge structure,and develops high-precision monitoring technology and equipment for bridge pile displacement.The main contents of this paper are as follows:(1)The influence mechanism of tunnel construction on adjacent bridge pile foundation is studied,and the methods,advantages and disadvantages of bridge displacement monitoring at home and abroad are summarized.(2)Using force method and displacement method,the influence of longitudinal uneven settlement of pile foundation on the internal force of superstructure of continuous beam and rigid frame bridge and the influence of lateral uneven settlement on the internal force of lower structure of double-column portal pier are analyzed quantitatively.The influence of lateral uneven settlement and horizontal deviation of pile foundation on bridge structure is qualitatively analyzed.(3)This paper puts forward the technology of micro-deformation monitoring of pile foundation based on dual inverse perspective mapping,deduces the formula of dual inverse perspective mapping suitable for this monitoring technology,introduces the image recognition program Spot detector and RBF neural network technology used in this technology center,and makes a preliminary research and development of the product.This monitoring technology is also the innovation of this paper,which is a supplement to the existing bridge displacement monitoring technology.(4)Experiments are designed to verify the correctness and feasibility of the micro-deformation monitoring technology based on dual inverse perspective mapping.The accuracy of the technology under the existing test equipment is analyzed,and problems are found in the test,which lays a foundation for the follow-up research.(5)Midas/Civil software is used to analyze the influence of settlement and horizontal displacement on the structure of the fourth bridge in the fourth section of the coastal highway.The monitoring scheme of the bridge is given,and the micro-deformation monitoring technology of pile foundation based on double reverse perspective is applied to the real bridge monitoring.