Research On The Construction Control Technology In The Over Framing Of Continuous Bridge

With the extensive application of prestressed concrete, bridge superstructure construction method has also been great progress, the method of local casting has become one of the main construction methods because of convenience. the method is that we puts the bracket in the bridge position, pour the concrete to the bracket and move the bracket after achieving the strength of concrete. This support system are multi-pivot bearing system, distribute load in multiple fulcrum, Send the load to the foundation, So the foundation must have sufficient bearing capacity, while requiring all pivot sink together. To prevent the girder due to uneven subsidence arising from cracking. Coupled with the carrying capacity of bracket is very large in the construction, In order to achieve security, economic, the layout of the bracket should be necessary and reasonable, it is extremely important to analyse the bearing capacity of bracket.The support cast-in-place construction, first the support design should have the enough supporting capacity and the overall stability, must carry on in detail examines calculated, including support supporting capacity, ground supporting capacity computation as well as stable analysis and so on. The support design examines calculated that, should consider following load:Weight of box girder, template and support; Construction load; Wind load; If in north winter construction, but also should consider the snow load and the heat preservation maintains the facility load; In the water constructs also should consider the running water lateral pressure. For Beijing-Shanghai high speed railway bridge span A5 side & middle span support design, this article author uses structural design software Mdias v5.6.0 to carry on the overall modelling computation,In casting process, over framing various support members stress and distortion; In the casting process, the structure overall stable mechanical analysis, the author uses the subspace repetitive process computation structure the base frequency and inspires correspondingly before, and withdraws 10 step frequencies and inspires correspondingly explains the question. Regarding the ground supporting capacity, the author through the theoretical formula computation, the synthesis contrast sand pile, the CFG pile, ground reinforcement and so on high-pressure spray note thick liquid effects, has recommended the suitable over framing ground processing plan.