The Comparison And Selection Of High Pier Type On Prefabricated T Girder Bridge

In recent years,with the rapid development of economic,the development of the freeway extends from the plain area to the mountainous area.Meanwhile,because of implementation of western development strategy,there are more and more new projects in the mountainous freeway.The western mountain terrain undulation being big,mostly in mountainous area,in order to ensure the freeway alignment,it is necessary to build a bridge across the valley or river.But in some mountainous areas,the elevation difference is very big,we need to pay special attention to in the design of high pier bridge.For the mountainous area freeway bridge,due to the bridge no shipping restrictions,in bridge design process,people are usually in order to meet the need to design the mechanical properties of the pier.There isn`t uniform design standards between different designers.The standardization of the precasting and assembling structure is conducive to shorten the construction period and reduce the construction cost of the project,some of the high pier bridge with long span prestressed concrete continuous rigid frame,but taking into account the standardization construction of superiority,the bridge often use to conventional span beam bridge that the span is 40 m,section type selection of prefabricated T beam and box girder.The continuous rigid frame bridge with T beam is a continuous beam bridge.It is the first simple support after the structure of a continuous form,the structure of small deformation,large rigidity,less expansion joints,comfort,good seismic performance,easy maintenance and so on.In this paper,the main research mountain freeway assembly type T beam bridge high pier type and classification summary and analysis of different pier within the height range of commonly used types of piers.On the basis of the investigation and analysis,combined with engineering practice the corresponding calculation model is established for studying different types of piers which under dead load,live load,temperature,bearing subsidence,earthquake force lead to the action of pier structure effect,calculate the pier by the size of the axial force,bending moment,shear force and reinforcement calculation so as to meet requirements.Then select the best type of pier by the static analysis,dynamic analysis,construction methods,cost,beautiful and other aspects.Through comparisons,the 40 m assembly T beam bridge when high piers in 40~50m it is used to double column cylindrical pier;high pier 50~60m to the occasion with double column type hollow pier;pier height of 60 m above the occasion with double column type hollow pier with thin wall and hollow thin-walled pier,but considering the double column type hollow thin-walled pier construction than thin-walled hollow pier complex,mechanical properties are similar,so the main recommendation with hollow and thin-wall piers.The research results of this paper can provide reference for the design and selection of the bridge pier in the mountainous area,and has important in engineering application value.