Study On Cantilever Casting Technology For Geometric And Mechanical Performance Of The Long-span Prestressed Concrete Continous Rigid Frame Bridge

The prestressed concrete continuous rigid frame bridge is widely used because of its convient construction,long-span ability,economical cost,high strength,reasonable internal force and comfortable traveling.Symmetrical cantilever pouring construction is usually adopted in many construction ways,however,during the process of the symmertrical cantilever pouring construction,various factors which affect the bridge structure,such as the modulus of elasticity,temperature,shrinkage,creep of the concrete and so on.Besides,the beam axis shape of formed blocks can not be regulated during the next construction.For the construction of the bridge is all right and the beam axis shape is exactitude,for internal force of the beam is appeased by design request,must to study on cantilever casting technology for geometric and stress control of the bridge during the process of the symmertrical cantilever pouring construction.The paper through analysis and summing-up the development of the long-span prestressed concrete continuous rigid frame bridge,the construction control techniques and the control theory in the project practice in our country and abroad.The text combines the project practice of the Zhuisan River prestressed concrete continuous rigid frame bridge in north along the river between Chaohu and Wuwei in Anhui.Besides,the paper studys on the key techonologies of the Zhuisan River prestressed concrete continuous rigid frame bridge symmetrical cantilever pouring construction.And using the finite element anslysis software MIDAS/Civil to simulate the diamond hanging basket,ensure the safety of using it.In addition,puts some keypoints during the construction.The paper which focus on the long-span prestressed concrete continuous rigid frame bridge,by using the finite element anslysis software MIDAS/Civil to establish the simulation model on the construction stage.Besides,it pays more attention to the analysis of partial stress for the zero-block of the ZhuiSan River Bridge duing the maximum cantilever bridge state combining with the finite element analysis software ANSYS.Finally,this paper researches the influences of the concrete density,the concrete elastic modulus,temperature and concrete shrinkage and creep on the continuous rigid frame bridge upper structure linear and stress.The studies show that:The diamond hanging basket in practice construction can meet the construction requirements;The forces of rigid frame bridge are almost compressive stress,only certain connnection parts appear tensile stress even more than standard design value,and needs to be paid more attention to in the construction.Concrete density and temperature which have great influence on the linear and stress of the bridge and the influence of the temperature is obvious;The concrete elastic modulus which affects the linear of the bridge obviously,however,the influence on the stress can be neglected;Besides,the influence of the concrete shrinkage and creep on the stress and the linear is obviously.The conclusion of the paper can be the basis for further improvement of continuous rigid frame bridge design and construction.