Study On Mechanical Behaviors Of Y-shaped Bridge Pier Under Dynamic Loading

The bridge is a transportation lifeline, domestic automobile traffic is increasingin the current, it has brought the huge challenge for the bridge construction ofcity,city viaduct, viaduct is increasing day by day, pier columns of rectangular aboutsingle column form is the major in city bridges, the structure have concise and smoothappearance, occupying less land under the bridge, improving the lower structurelayout, reducing the cost, increasing the field of vision and the bridge shapedappearance,and pier site settings is convenient in The complex linear bridge of theMulti-layer, so the bridge of single column pier is widely applied in city bridge.Compared with the single column pier, transverse spacing is distant about doublecolumn bridge pier, lateral force is better, but the traffic organization is not facilitateunder the bridge, and effecting the landscape. And the use of single column pier canreduce the number of pier column, increasing the clearance under the bridge, makingthe line of sight concision, light, it is a better choice in city bridge. In orderto satisfy the ability to stay stabilization, for the single column pier bridges, increasingthe spacing between bearings. In recent years, there have been shaped pier more, theform of “Y” type pier is one of the common structure. Due to large rigidity, thecontinuous beam with the pier top set fixed support, its seismic performance is difficultand the controlling factors of the pier design. In view of the defects of continuousbeam of single column pier, this paper presented some different kinds of “Y” type pierand some control factors have influence on seismic performance of “Y” type bridgepier. Using the design response spectra of flexural to find the capacity of bendingability and the shear bearing.Compare the result of different kinds of “Y” type pierswork on the seismic stress performance, provides some references tothe future city viaduct pier. This paper selects Y type pier girder bridge as the researchobject, make a research on the mechanical properties and resistance to capsizing.Themain contents are as follows:(1) choose the ratio Z as control factor, which is ratio that the high of some of theabove fork pier and the lower part of the single column pier high, we selected theredifferent Z values of the pier,2/9,3/8,5/6, use of software to analyze the earthquakecycle, pier under earthquake modal, flexural bearing capacity and the shearon different Z values. (2) choose the pier bifurcation angle values as control factors, select threedifferent bifurcation angle pier, use the software to analyze bridge pierunder earthquake cycle, the earthquake modal, flexural bearing capacity and flexuralbearing capacity on different bifurcation angle.(3) choose the height value of pier as control factors, we selected7m,11m,15mthree kinds of high pier bridge pier, use the software to analyze bridge pier under theearthquake cycle, seismic modes, ultimate flexural capacity and shear capacity ondifferent pier height, and select a “Y” type pier on the in the normal operation of thewhole stress analysis on different pier height.(4) choose a “Y” type pier and rectangular pier to calculate the factor of safetyagainst overturning, and compared with the rectangular pier. Using safety evaluationindicators of anti-overturning to measure the anti overturning ability.