Research Of Construction Monitor Control About Spatial Torsional Tied-arch Bridge System Conversion

Spatial torsional tied-arch bridge is a brand-new structural style of bridge. Because of thedistinctive modeling and lightsome beautiful appearance, it has been got application anddevelopment in city bridge construction of recent years. But the main arch reverses outward anangle after introverting which leads the complicated stress and difficult construction, so it’snecessary to control the whole construction process. Specially, for the great influence of keyconstruction system conversion, it must be strictly controlled, or the subsequent constructionand ideal goal of bridge would be affected. In view of the above question, several criticalsegments of system conversion were researched with YangHu Bridge for engineeringbackground, and the main finished work was as follows:1. For the particularity of the main arch and supporting system, the process of removingtemporary supports becomes more complex in the formation stress system of the arch structure.The finite element model about the process of removing temporary supports in ANSYS wasbuilt by choosing available finite element, and different schemes were simulated at the basic ofForward-analysis method. The simulation results showed that the value of stress and deflectionby monitoring scheme was less, so the scheme was carried out to guide the construction ofremoving temporary supports.2. Tensioning in hangers is a vital part of the whole construction system conversion, andthe arch and beam closed system is gradually formed in this stage. Optimizing the order oftension can effectively reduce influence to the structure and secure safety of the construction. Awhole bridge model was established by ANSYS based on backward sequence method aftercomparing the various methods for calculating the tension. For solving the optimized order,designated section stress of the arch rib, initial tensioning force in hangers and the hanger forcein tension process were used as controlled object, and a circulation flip program was scheduledby APDL. Related test was executed after constructing with the optimized order, and the resultsshowed that the optimized method was correct, the safety was ensured also.3. Controlling the line shape of the arch while tensioning in hangers can reach the idealtarget after construction. According to the problem of deviation of arch deflection betweentheoretical and measured value, a theory model of end correction in tension was builded bygeneral discrete linear system Kalman filter. The error was finally in a certain range byconstantly measuring and adjusting the cable force. The system conversion of tied-arch bridge is researched in this paper, the gains were usingin construction control of YangHu Bridge, and good results have been achieved. The researchachievement of this paper can also provide certain reference and model to similar bridge.