Construction Scheme Optimization Of The Reinforced Concrete Arch Bridge Pouring On The Arch

When the bridge span is 80 ~ 200 m,the reinforced concrete arch bridge has a great competitive advantage,especially in the western mountain area such as yunnan,guizhou,Sichuan,etc.For larger span reinforced concrete arch bridge,the suspended splicing steel arch is usually used aided structure as the cast-in-place arch ring construction,then how to determine the dividing construction scheme,and how to consider the influence of combined effect are key points,still has some problem to study deeply.This paper bases on the Ganhegou bridge in Guizhou,taking some research about the optimization calculation of its construction scheme.The main research content and achievement of this article is as follows:(1)This paper introduces the construction method of reinforced concrete arch bridge and it's application in mountain areas,mainly describes the research status of steel arch construction,and analysis the lack of current research in steel arch construction arch ring.(2)Based on the Ganhegou bridge in Guizhou,by model building for the original construction scheme of the arch ring using the finite element calculation program BR-CAL-Z,according to the situation that appearing the most unfavorable stress in the arch ring during the construction process,analyzing and optimizing the concrete pouring sequence of the arch ring,raising the optimization algorithm basing on permutation and combination,realizing the force of arch ring under the construction process and the completion state tend to be more reasonable,getting the construction scheme after optimization.(3)Based on the better construction scheme after optimizing,for the situation that the force of arch overrun or the arch design over-conservative when treat the arch ring concrete as load,analyzing the reinforced concrete arch bridge by finite element.Respectively contrasting the key parts' chord stress of the arch considering the combined effect and independent effect,analyzing the changes of arch stress.It shows that after considering the combined effect,the force improved,when pouring the web,the stress of every key chord reduces 16.5%~61.5%,when pouring the roof,the stress of every key chord reduces 23.4%~58.3%.Then contrasting the measured value to the theoretical value to prove the above conclusions.So the combined effect is actually exist in the construction process.(4)Using the same method to study the key parts' node displacement of arch considering the combined effect and independent effect,analyzing the changes of arch deformation.It shows that the combined effect has a great influence on the deformation in the construction.when pouring the web,the stress of every key chord reduces 21.14%~58.83%,when pouring the roof,the stress of every key chord reduces 29.43%~67.13%.Then contrasting the measured value to the theoretical value to prove the above conclusions.