Railway - Span Prestressed Concrete Continuous Rigid Frame Bridge Construction Control

Because of convenient construction, economy cost, reasonable force, driving comfort for prestressed concrete continuous rigid frame bridge, it was widly used in China, and bridge with 100～300m main span was almost the first choice.But in cantilever construction process of prestressed concrete Continuous rigid frame bridge, built beam block could not be regulation in the late construction, for guarantee linear and internal force of bridge in design control range in close up of cantilever, construction control work must be done in bridge construction. In this paper,FEA methods was used in simulating constrution behavior of Dukouhe Great Bridge, and pre-camber in main beam construction, then FEA model was real-time amendment according to contrasting data collected in construction , finally made linear of main beam and force behavior to meet the design requirements.According to made constrution monitoring, main beam linear and stress meet control target, and meet design and codes requirements; because ridge of pier of railway bridge is big, 128m pier's settlement was 2mm in main beam construction according to monitoring, so there was no secondary stress in continuous rigid frame bridge construction, which show bridge structure is safe and reliable.Research shows that high pier settlement and displacement of the continuous rigid frame bridge beams internal forces have a greater impact, high-altitude winds on the size of the bridge closure also has a non-precision small.On the whole,in construction monitoring process of Dukouhe Great Bridge,if improve the accuracy of monitoring, a monitoring system with monitoring function on displacement, temperatur and strain and so on was needed. But a system like that would need more expensive, so it was rarely used in bridge monitoring in China. At the same time, an auto-control system must be set up based on Automatic Data Acquisition System.