Technology introduction: This technology conforms to the construction concept of new era, "People-oriented, green and environmental protection", and systematically solves the technical difficulties of demolition, lifting, transporting, debarkation and safety control of concrete box girder bridge, which provides complete set of technology for security evaluation, structure design, scientific construction and safety control of the demolition of curve girder with equivalent section and straight girder bridge under complex situations (e.g. no interrupting traffic around the bridge during construction; there is no enough space for lifting nearby the target bridge; there is no large lifting equipment in the construction site; the target bridge's headroom is too high), and also provides a complete set of theory and methods for the lifting, jacking and dismantling of the same or different kind of bridge as a reference, which is of good application and promotion prospect and potential huge social economic benefits.
Innovations: (1) Based on the deck support system, the whole-span box girder demolition system is developed, in which the technical process is clarified, the calculation method of lifting force is put forward and the complete set of demolition technology that the computer controls the hydraulic pressure to synchronously lift the 400-ton concrete-curved-box-girder is formed. (2) Based on the deck support system, the whole-span box girder demolition system is developed, in which the technical process is clarified, the calculation method of lifting force is put forward and the complete set of demolition technology that the computer controls the hydraulic pressure to synchronously lift the 1000-ton concrete-curved-box-girder is formed. (3) The safety control methods and technical principle of the demolition of the whole continuous beam bridge with equivalent section are put forward, in which the evaluation index, content and pre-warning value of safety control of the demolition of continuous beam bridge with equivalent section are clarified.
Technical features: (1) Construct under the conditions of not interrupting the traffic, narrow space, large clearance and so on. (2) It conforms to the structure safety, construction safety, traffic safety and environment safety. (3) The structure system transforms steadily; the demolition system is controllable; demolition technology is steady. (4) Safe, adaptive, quick, environmental, economical.
Application cases: The research achievements are successfully applied in the following projects: the demolition project of No.3 bridge of the ramp of Longxi viaduct; the old bridge demolition project in the south and north side of the Guanlan River Bridge.