Investigation Into Seismic Analysis Of Space Curved Bridge In Interchange

The current seismic design principles of conventional bridge are becoming more perfect, earthquake response law of unconventional bridge is still at the exploratory stage because of many factors. The large-scale interchange is a collection of various unconventional bridges, there are special-shaped plate girder, curved bridge and the slope bridge, the space line is ups and downs in form and structure is varied, almost all the interchange is space curve, their seismic response is complex.In order to reveal the response law of spatial curved bridge under earthquake,this according to the provisions of longitudinal and radius of curvature in Interchange Project for road grade, speed, site conditions, comparative analysis by establish some finite element model,the mainly studies as following:1. Using the special software of bridge Midas/civil establish the number of finite element model which can consider the longitudinal and radius of curvature, summed up the laws how can slope and the curvature radius effect the force of bridge.2. The internal forces of curved bridge present certain changes of the cycle by the central angle increasing by comparative analysis.3. Curved bridge girder bear in two directions combined effect of bending moment and torque. Under the earthquake effect, the moment Mz is larger and in the middle span is largest and decreases continuously to both sides. The maximum bending moment Mz been offset to the direction of short pier with the longitudinal increased. As the radius of curvature decreasing, the bending moment Mz growing.4. Transverse displacement of the main beam is limited, a larger force transverse to the pier. Short pier suffered a larger internal force, deformation small, there is the possibility of strength failure. Seismic, structural changes in displacement and internal force is not proportion as the existence of non-linear.