Research On Construction Technology Of Shiji Passenger Special Double-track 40m Cast-in-situ Box Girder By Movable Scaffolding System

Movable Scaffolding System is a kind of equipment used in the specialized construction of large bridges,and a system in which active displacement can be carried out between bridges and formwork can be carried out as support and bridge fabrication support when concrete box girders are poured.Compared with the traditional bridge construction technology,Movable Scaffolding System construction technology has the following characteristics.It integrates formwork system,support system and hole-passing function.It has many advantages,such as programmable procedure,easy control of alignment,high degree of mechanical automation,no foundation treatment,wide application scope,little influence on construction traffic,safe and reliable operation,etc.It is widely used in the construction of high pier highway bridge,high-speed railway bridge and river-crossing sea bridge.Taking the construction of MSS40-1200 downward Movable Scaffolding System in 40 m cast-in-situ box girder of 46 holes of Hengjing super large Bridge of Shiji Passenger Special Project as the engineering background,starting from the characteristics of Movable Scaffolding System,this paper analyses and introduces its main structure,working principle and technical parameters,and describes the working procedures of Movable Scaffolding System from assembling,preloading,through holes to demolition,such as the installation of supports and formwork installation of cast-in-situ box girder construction,technology and control measures of steel bar binding,concrete pouring and maintenance,pretension grouting,etc.Combined with the problems in practical application,the advantages and disadvantages of Movable Scaffolding System for cast-in-situ box girder construction are analyzed,and the improvement suggestions are put forward,and the development direction of Movable Scaffolding System method is put forward.