Research On Construction Design Of Precast Splice Of Simple Supported Box Girder In High-speed Railway

Wth the characteristics of a large bridge proportion,the high-speed railroad bridge construction organization directly related to the construction period,project quality and project cost of the high-speed railroad of the high-speed railroad, which is the difficult problem abou technology and management required solution urgently.The high-speed railroad bridge is different with the bridge of ordinary railroad and highway by the rigidity,the integrity,smoothness,advantageous for service and so on.The special request makes the high-speed railroad bridge use the small or medium span freely supported box girder,the majority using the frame girder generally.Because the constructon of the high speed railway in China has just started,the bridge construction methods and construction design still in the exploratory stage,therefore,the construction organization research of the high-speed railroad freely supported box girder has a great theoretical and practical significance.Construction organization of the high-speed railroad freely supported box girder include the bridge construction technology,the choice and design of engineering equipment,the analysis and design of construction period,how to do frame girder and so on.This article analyzed and researched construction scheme of construction technique and equipment,time limit for a project,scheme of how to make,transport and erect girders,setting and site selection of girders factory,plane layout,detailed design and cost analysis of high-speed railroad freely supported box girder in China,which based on reaching and summing up the theory and experience of China`s existing construction organizations of dedicated-passenger railway lines and theory and practical research achievement at home and abroad.The following is the main conclusion and innovation spot:The bridge of high-speed railway must have sufficiently large vertical and lateral stiffness and good integrity,therefore,the high-speed railway bridge generally use the box beam,and a freely supported for the main structural types.The construction of the high-speed railway freely supported box girder should make girders all in the factory which is set on the spot,and transport the girders by wheel-type trucks.It should use 900t bridge erecting machince as the main construction scheme in order to save investment and project construction period,guaranteeing the construction quality of box girder better.The supply scope of the high-speed railroad freely supported box girder factory should less than 35km.Radius of transporting and erecting girders should less than 18km.The erection of box girder should start 11-12 months after the startinf of the lower part engineering construction period is shorter than others,to shorter the construction period of engineerin.The location of girder factory should be near railway line which has a better geological conditions.At the same time,implement the principle of the economical use of land and making full use of formal land for the engineering,saving engineering investment.The scale of the girder factory should be determined after the technical and economic comparison,and be based on construction period and tooling equipment situation.