Research On Bridge Expansion Plan Based On Concrete Shrinkage Creep And Foundation Settlement Theory

With the development of transportation in our country,the capacity of the early highway has been increasingly saturated,and part of them can not meet the demand of traffic growth.Many early constructed bridge can not meet the requirement of the traffic growth,or above the bearing capacity of the original bridge.Based on the existing bridge traffic capacity and carrying capacity in highway reconstruction projects,in order to meet the demand of transportation and improve the traffic capacity and service level of highway in the future,either reconstruction,or extension bridge,or reinforcement on the original bridge.Of course,if the early bridge can meet the traffic capacity and carrying capacity in the future,it could be continued used.But when we expand its capacity by spelling the bridge,the most important thing is the deformation and the stress of coordination between the old bridge and new bridge,On the bridge expansion project,the settlement,shrinkage and the creep deformation of the old bridge has been basically or nearly complete,but the new bridge have a large settlement,shrinkage and creep,the deformation of them lead to produce deformation differences between old bridge and new bridge.It is necessary to make a research on settlement,shrinkage and the creep between the old bridge and new bridge,so it can make some suggestions and theories on the bridge expansion project in the future.In this paper we writing by Long Yin No,1 bridge as background,using the concrete shrinkage and creep calculation theory and finite element software Midas Civil,deeply analysis the influences of creep,shrinkage and the foundation settlement differences bring additional force into the upper structure of the bridge.This paper carry out the following works:(1)By analyzing and collecting the related literature in domestic and overseas,summarizing commonly used construction methods and applicable conditions on the bridge expansion projects.(2)Analysis the calculation methods of creep and shrinkage,summarize concrete under different external factors shrinkage,creep calculation methods,applicable conditions and existing problems.(3)Combined with the calculation method of concrete shrinkage and creep,using the finite element software Midas Civil space grillage method analysis Yunnan province secondary highway rebuilding Long Yin No.1 bridge expansion project.After the expansion project,concrete shrinkage,creep of the old bridge have done the most,the concrete shrinkage and creep of the new bridge is just beginning or has yet to be completed,the concrete shrinkage and creep differences between the new bridge and the old bridge will generate additional internal force and deformation into the upper structure of the bridge.Analysis the change laws of additional internal forces and deformation displacement.(4)As a result of the new bridge foundation settlement has yet to be completed,and the foundation settlement of the old bridge has been basically completed,the settlement differences will lead to the additional internal force between the new bridge and the old bridge,analyze the influence of additional internal force bring the impact to the bridge structure and the change laws.(5)Comprehensive analyzing the concrete shrinkage,creep and foundation settlement differences between the old bridge and the new bridge bring the additional internal force deformation influences and the bridges itself stability influence.(6)According to the result of simulation calculation and analysis of the related bridge design theory and construction methods.summarize and put forward some scientific and reasonable engineering measures about reducing the concrete shrinkage,creep and foundation settlement differences impact on the bridge,...