Research And Practice On The Cantilever Construction Control Technology Of (60+100+60)m Continuous Beam

Prestressed concrete continuous beam bridge is widely used due to its advantages of strong span ability,large torsional stiffness.However,due to the increasing crossborder construction of the bridge,the construction difficulty is increasing,and various factors will also affect the linear shape of the continuous beam,If not corrected it in time.It may lead to difficulties in smooth closure and high construction risks.On the basis of research and summary of construction control technology in China and abroad,this paper studies the(60+100+60)m Langfang to Zhuozhou Intercity Guba Great Bridge.The main work is as follows:(1)The finite element model of the continuous beam is established by Midas/Civil2019,the finite element simulation analysis of the continuous beam is carried out,and obtain the theoretical deflection,stress diagram and key cross-section theoretical stress from the model.(2)Carry out sensitivity analysis on the parameters affecting the construction of continuous beams,including volume weight of concrete,elastic modulus of concrete,prestressing,etc.,and put forward the error adjustment method of Grey System Theory,to solve the error correction problem in the actual construction process.(3)Use Midas/FEA to establish a solid model of block No.0,and the stress field analysis of block No.0 in the maximum cantilever stage and completion stage is carried out;(4)According to the actual construction scheme,the field measured data are compared with the data obtained by calculation and analysis,so as to correct the relevant data and guide the construction.The monitoring results show that the continuous beam alignment and the key section stress meet the requirements of the design and relevant specifications,indicating that the construction scheme of the bridge is reasonable.