Researches Of Design And Construction On Ultra-small Angle Skew Frame Bridge Of Under-cross Railway

With the development of the communication and transport, frame bridge is widely used in the interchangeable junction of highway and railway. Due to the limit of the original building, the existing line or econgmic factors, frame bridge is often required to be a small skew angle, so the amount of ultra-small skew angle frame bridges increases fast. It is more and more important to conduct the mechanical behavior analysis on the ultra-small angle skew frame bridges. This paper is based on the background of Xinyue railway frame bridge. Study the mechanical characteristics of the ultra-small angle skew frame bridge in the design and construction process, by constituting the model with the finite element analysis software Midas/Civil. This dissertation has mainly dealt with the following respects:(1) The construction process, construction technology and some common problem of the ultra-small angle skew frame bridge were introduced in detail.(2) The impact of internal force of frame bridge resulting from different skew angle are analyzed. Study the characteristics of internal force of the ultra-small angle skew frame bridge by the comparison; the stressed state of frame bridge with different skew angles during the jacking construction process was analyzed.(3) The model of the whole Xinyue railway frame bridge was established. The impact of different ground conditions including different coefficient of subgrade reaction and uneven foundation settlement on the structural bearing capacity of the frame bridge was researched. the3-D stresses of locations of this frame bridge during the jacking construction process was also analyzed, which determine the areas needed to monitoring. The content of this paper is combined with practice, and some conclusions or suggestions provides an useful reference during the similar construction stage.(4) The reasons of cracks on the roof and side walls of this frame bridge were analyzed, and the reasonable reinforcement of the ultra-small angle skew frame bridge was introduced.