The Research On The Cast-in-place Construction Control Of Concrete Arch Bridge

Reinforced concrete arch bridge structural performance is superior,spanning capacity,durability and economy is good and beautiful,so the project is favored by the industry.Arch method is a commonly used construction method of concrete arch bridge.The construction method of arch bridge contain: the hoisting of the steel arch construction,steel arch preloading construction,the main arch ring section construction,steel arch frame falls construction etc,construction procedures and construction control is difficult,there are still a lot of issues worthy of further study.This paper takes Guizhou Gan He Gou Bridge to be Engineering background,doing the arch of cast-in-situ concrete arch bridge construction control research,the main work and results are as follows:(1)This paper introduces the construction control of concrete arch bridge in Guizhou Gan Gou Bridge content,factors affecting the accuracy of construction control,key points and difficulties in construction control ect,through the whole process of construction control simulation analysis to determine the cable force and the steel arch assembly line.In the steel frame assembly and pre press process,put forward and adopted “The main of Linear control,Supplement of stress control”,to guide the smooth progress of the construction.(2)Currently the determination research status of arch cast-in-place arch concrete pouring sequence mainly consider arch deformation without considering the structure,takes Guizhou Gan He Gou Bridge to be Engineering background,according to the construction scheme determine the sub segment location,the use of MIDAS software for construction of cast-in-situ concrete arch arch of the whole process of simulation analysis,considering the deformation and stress of arch structure,the reasonable pouring scheme is determined by the comparison of the multi scheme calculation: The first concrete castingg sequence is arch foot section first,then the vault section,last the middle section;Second concrete castingg sequence is arch vault section first,then the foot section,last the middle section;The vault section,the foot section and the middle section of the third ring concrete castingg sequence are both subdivided into two parts,the part 1 castingg sequence is arch vault section first,then the middle section,last the foot section;the part 2 castingg sequence is arch vault section first,then the foot section,last the middle section;construction on the arch castingg sequence is from arch vault to arch foot.The deformation and stress of the arch structure theory is in good agreement with the measured values,the method is reasonable and reliable,can reference for design and construction of the same type of bridge.(3)According to the present situation of construction of large span concrete arch bridge steel arch overall unloading research of construction process,the main bridge of Guizhou Gan He-gou Bridge as engineering background,the construction process of large span steel arch overall unloading by using the finite element software MIDAS simulation analysis,considering the stress and deformation of arch and arch,according to the comparative analysis of multi program trial calculation: the whole steel arch landed on both sides of the arch foot while unloading or unloading are in turn is reasonable and feasible,in the steel arch 4cm before unloading process,can use each drop height 1cm project construction;after this,it can be used in the construction of the 2cm of the construction is reasonable and safe.The research results of this paper ensure the construction safety of the bridge and the smooth implementation of the bridge construction,can provide some reference for similar long-span arch bridge construction control.