Construction Control For Prestressed Concrete Continuous Bridge

Prestressed concrete continuous girder bridge is a bridge type of long-span Bridges,it has many advantages and be widely used.The use of Cantilever casting method make the prestressed concrete continuous girder bridge’s chang of internal force and displacement complicated.In order to ensure the engineering quality and safety,an engineering control system of bridge must be brought in to implement the requirements of geometrical aesthetic appeal and internal force. With the engineering background of Huaihe river extra large bridge,by using the construction control method of self adaptive method,the implementation of construction monitoring of Huaihe river extra large bridge was complished.As a result,the geometrical aesthetic appeal and internal force of the structure met the requirements.The main research works and conclusions of this paper are as follows:1.Finite element model of the main bridge of huaihe river extra large bridge was established by using the finite element software Midas/Civil rely on the structural characteristics of this bridge,the stress and deformation of bridge in the whole construction or finished bridge structure were analyzed,the sensitivity of parameters which effect the bridge geometrical aesthetic and structure stress were analyzed,the influence rules about the bridge geometrical aesthetic and stress of key parameters were obtained.Calculation results show that the internal force of the bridge meet the specification requirement, there is no overstress.2.The analysis of the temporary consolidation points was complished,the calculation results show that the design of the temporary consolidation points is reasonable,it can ensure the stability and safety of the bridge during construction. Against the problem of prestressed concrete continuous bridge shut under high temperature,change scheme of bridge’s closure has been proposed. Between different shut methods,the calculation results show that there is little effect about the bridge geometrical aesthetic and stress, the problem of weak integrity of closure segment and larger secondary internal force after shuting were solved. Using the proposed changing schemes for the girder closure during construction,the result was perfect.The temperature load effect about maximum cantilever state’s and finished bridge’s geometrical aesthetic and stress were analysed,the result provide reference for the stress’s and deformation’s amendment.3.The bridge construction monitoring scheme of the main bridge of huaihe river extra large bridge was established，guided the bridge’s construction monitoring work.4.Construction monitoring was implemented,according to the results of site test,the theoretical parameters was amended.After this the theoretical parameters conformed to the actual situation,so as to guide the bridge site construction.Through the stress monitoring,the internal force of bridge structure was reasonable and the construction is safety;according to the analysis of main girder’s deformation data，main girder deformation laws were mastered.By comparing the measured values and the theoretical value,laying elevation of each section of the main girder was determined,as a result the alignment of bridge was smooth,the closure deviation conform to specified requirements.The comparison of the measured result and the theoretical result shows that theoretical result of the Huaihe river extra-large bridge’s main bridge’s geometrical aesthetic essentially agree with measured resut,there is little difference,the main bridge has smooth geometrical aesthetic and successful closure,indicators conform to specified requirements,the completed bridge’s geometrical aesthetic also conform to specified requirements.During the construction process,the Huaihe river extra-large bridge’s main bridge’s measured stress result of every control section conform to theoretical result,the structure state is safety.The above results show that the construction monitoring of the Huaihe river extra-large bridge’s main bridge has reached the intended destination,the completed bridge’s internal force and alignment meet the design requirements.