The Research On Construction Monitoring Of The Main Bridge Of Zhao He Bridge Which On The Ningxi Railway Second-line

Concrete-filled steel tubular arch bridge(CFST) has the advantages of high strength, light weight, beautiful appearance, convenient construction, suitable to construct of large span bridge and other, in recent years in the bridge engineering of China has been widely used. The process of CFST arch bridge construction is a complex and multi factor process, to ensure completed successfully and meet the design requirements, the construction monitoring and analysis of the bridge is in need. Based on the 64 m span CFST arch bridge of the Zhao River Bridge Main Bridge which on the Ningxi Railway Second-line form Xi’an to Nanyang, this paper establish the finite element models to carry out the construction site monitoring. At the same time to ensure the good effect of bridge construction monitoring, the research on the arch rib perfusion sequence and the sensitivity analysis and identification of the structure parameter has been done. The main contents are as follows:(1) The Zhao River bridge finite element model is established by the finite element software Midas/civil. Using Combined Section Method to simulate the arch rib and calculate the key process for the construction of arch rib perfusion, the stress and displacement of arch rib in different pouring sequence are compared and analyzed, the reasonable perfusion sequence of the bridge are identified.(2) Through the sensitivity analysis of the structure parameters which used the deformation of the tie beam as the control target, we can compare the influence degree of structure parameters on the control target, and determine the main structure parameters, and provide the basic data for calculating the parameters of the model.(3) Combined with the Zhao River Bridge structure characteristics and construction technology, establish the bridge’s construction monitoring program, monitor the stress and deformation of the beam and arch rib on the construction process, monitor the suspender force and environmental temperature.(4) To carry out the on-site monitoring work of Zhao River Bridge, The least square method is used to identify the the main structure parameters. According to the recognition result of the structural parameters, the finite element model has been corrected. In each stage of construction, the theoretical values and the actual results of structure state are compared and analyzed. The results show that: the measured values of can better approach the theoretical value, and that the site construction monitoring of the Zhao River bridge effect is good.