Construction Monitoring Of Long-span Beam Bridge

In recent years， with the rapid development of transport， pre-stressedconcrete continuous girder bridge has grown up to one of the primary bridges withits predominance of riding comfort and long span. Most of pre-stressed concretecontinuous girder bridge with economical and rational Cantilever ConstructionMethod, but this construction method will bring more power and flexibility ofcomplex changes in stress. The inner forces and configurations of large-spanpriestesses concrete continuous bridge using the cantilever construction methodmay deviate from the design values due to the following factors， such asnon-homogeneity of concrete，properties，variations of geometric parameters，temperature humidity and time etc. In order to ensure the quality of bridgeconstruction and bridge construction, safety and reduce the main beam possiblefuture long-term deflection, bridge construction is essential links and measures. Byfinite element simulation analysis and field data measured on the Quiche Bridge,the results showed that: the test section stress measured value and theoreticalcalculated values agree well with the linear, the internal forces and bridge line alsomeet the design requirements well; Temperature gradients have large differenceswith each other, so the design should be selected to be consistent with thetemperature gradient mode. The main beam stress caused by the verticaltemperature is even larger than the stress caused by the live load, therefore, moreattention should be paid to the vertical temperature effect in design; In the processof building the continuous beam bridge，mechanical properties and economicalproperties should be both considered in the selection of temporary constructionfacilities, and the selection of steel support is also based on this consideration.Combine the environmental conditions to select a reasonable temperature patternand use a appropriate method to analysis internal force of the steel-frame. Theresult showed that the steel-frame meet the requirements of this project.