The Key Technologies Research in Demolition Construction of Liuxi River Bridge

Because the flow of river bridge was not suitable for bearing existing vehicle load, it is needed to be dismantled, and a new bridge will build on the original site. The overall construction plan is using double bridge girder erection machines to remove box girder and the suspended beam of the main bridge. In order to guarantee the security of assembling the bridge girder erection machines and lifting the beam, we did some research in assembling technology, using the finite element software MIDAS to establish model of sling equipment, and analyses whether the sling equipment can bear the design load. With the purpose of ensuring the stability and safety of the suspended beam in the process of hoisting, the suitable order of hoisting suspended beam and risk control of slipping the suspended beam were analyzed. For purpose of guaranteeing the stability of the hoisting box girder, the construction team designed the stabilization system. Due to the complexity of the stress of the girder in the demolition process, we use the finite element software ANSYS to establish the model of e box girder in the process of hoisting, and analyze its stress and deformation. According to the practical engineering, we draw a conclusion: the box girder, suspended beam remained stable in the process of hoisting, and their internal forces conform to the requirements of the specification. The overall construction plan can provide a reference for other similar projects.