Research On Analysis Methods And Force Characteristic Of Jointless Bridge

In the modern highway construction, concrete bridge for its lower cost and superiority in maintenance has already held over 90% of the total number of bridges. However, more and more expansion joints are liable to breakage in highway bridge, and it will be untoward and relatively expensive to replace or repair them. In many countries jointless bridge has been widely used, especially for small and medium span reinforced concrete bridges. the jointless bridge without extension joints, rigidly connect its superstructure with substructure, and it generally use the flexible foundation, and the bridge superstructure and substructure will has coordinate deformation in temperature load and others.Although jointless bridge has been widely used in past few decades, now the researchers design, calculate and analyze jointless bridge almost in accordance with practical experience, especially there is neither uniform standard to follow nor specification to refer in the design of its piers, abutment and the treatment of backfill on abutment. Therefore, this paper is to analyze jointless bridge mechanical behavior through finite element method, and to carry out the actual design and structural analysis of the relying bridge. The main contents of this paper are as follows:1, It is to proceed the jointless bridge structure analysis by using finite element method to establish ite beam element model in Dr.bridge and MIDAS/Civil, then to contract the two results to a computational method of jointless bridge. This section is to study the interaction of pile foundation and foundation soil which is been expressed as elastic restraint on the bottom columns in the model, and analyze the calculation of the elastic constraints in detail. in addition, soil pressure is considered with temperature change:when temperature rise, it is active earth pressure, and on the other hand is passive earth pressure, no longer simply ascertained a passive earth pressure, such combinations are closer to the actual effect earth pressure.2,Take Yubei River Bridge as relying bridge, and detailed design this jointless bridge according to the method of this paper, and it is focusing on the design of the bridge pier and abutment construction, in order to achieve the consolidation of the superstructure and substructure of the bridge, then they will bear the loads together and have compatible deformation. As for the treatment of the slab, there is a innovative way to increase the slab depth, which will take full advantage of the friction between the slab and the foundation soil to balance the internal forces caused by temperature change, and it is expected a good effect in future.3, There will be a internal force comparison between jointless bridge and continuous bridge after simply supported which has the same span, the same width and the same load case to the former. It is to analyze the jointless bridge's characteristic of internal force under the dead loads, vehicle loads and other forces, and some conclusions has been got which will provide a reference. for the further research, development and application on jointless bridge in future.