Experimental Research And Numerical Calculation Of Rapid Strengthening Method On Hollow Slab Bridge

The concrete hollow slab bridge has such advantages as light weight,assemble in site and standardized processes.Nowadays,it has been widely used in highway bridge engineering.However,with the transportation development,such as increased traffic volume and load levels,frequent heavy trucks,etc.,the original design bearing capacity has been unable to meet the practical requirements.Therefore,it is necessary to reinforce the existing problematical or damaged bridges.Concrete hollow slab bridges account for a large number in highway bridge projects at present.When the hollow slabs in service begin to occur unsafety or problems in service such as lack of lateral contact,veneer stress.If the method of direct demolition and reconstruction are adopted,it is not only uneconomical but also consumes a lot of time and cost.Thereby it may cause a series of waste of resources.Therefore,it is an effective method to avoid waste and ensure the reliability during the service period by using appropriate reinforcement technology to strengthen the diseased bridges.In order to improve the ultimate bearing capacity of the bridge and meet the various requirements,this paper aims to restore the flexural bearing capacity of the hollow slab bridges and the lateral connection by a new type of sticking steel board method without interrupting traffic.A simply supported hollow slab with a span of 8m was reinforced by pasting steel plates which was taking away from the Suizhong to Shenyang section of Beijing-Shenyang Expressway,and then the reinforced slab beam is axially loaded and eccentrically loaded.Finally,by the finite element software Abaqus,a series of e numerical simulation analysis on the hollow concrete slab was carried out to analyze the structural performance.Combining theoretical calculations,test results and numerical simulation analysis,this paper analyzes the improvement of the mid-span cross-section bearing capacity of the hollow slab beam after reinforcement,and the longitudinal transmission effect of the force by testing the stress on the concrete,steel bar and steel plate of the beam.Secondly,the internal forces of the two hollow slabs are analyzed under the eccentric condition.Based on the theory of the lateral distribution coefficient of load,this paper discusses the restoration of the lateral connection between the hollow slabs after reinforcement and the effect of the sticking steel board method on the structural improvement of the bridge.Finally,based on the existing calculation method of lateral distribution coefficient of load,the calculation model of lateral deflection of mid-span section under concentrated load is deduced,and the rationality of the above conclusion is demonstrated by the test results and Abaqus finite element analysis.In summary,without interrupting traffic,the bridge reinforcement method studied in this paper can effectively restore the lateral connection and improve the bending capacity of the hollow slab bridges.In addition,the calculation method of mid-section deflection provides a reference for future bridge reinforcement projects of the same type.