The Research On Health Evaluation Of Existing Hollow Slab Bridge And Steel Plate Reinforcement

Hollow slab bridge is one of the most important medium and small span bridges in the construction of highway bridges in china.With the increase of the service life of the bridge,a series of structural diseases appear in the hollow slab bridge under the influence of various factors.In order to ensure the structural safety of the hollow slab bridge,it is necessary to evaluate the health status of the bridge structure,and take measures to reinforce the serious parts of the hollow slab bridge structure,and the structural performance has been restored.Based on this,this paper studies the structural disease,health evaluation and reinforcement of hollow slab bridge,Firstly,the common diseases and mechanism of reinforced concrete hollow slab bridge are analyzed;Then,based on fuzzy evaluation method and analytic hierarchy process,a method of health evaluation for hollow slab bridge structure is put forward,and the application analysis is carried out with an engineering example;Finally,several existing reinforcement technology of bridge structure,the hollow slab bridge as the engineering background,using the finite element numerical analysis method,the effect of hollow slab bridge structure disease of bridges,and the reinforcement effect is verified by bonding steel plate.The main conclusions are as follows:(1)the common diseases of the hollow slab bridge are the cracks at the bottom of the plate,the failure of the joints between plates and the diseases of the bridge deck.The main causes of cracks in the floor include design factors,construction quality factors,maintenance and maintenance factors,vehicle load and natural environment factors;The main reasons for the joint failure include the design and the actual situation,the hinge joint structure and the improper selection of hinge joint concrete;The main key factor of bridge deck disease is early hollow slab design with low standard and small rigidity.(2)on the basis of the conventional evaluation method,a method of bridge structure health synthetic evaluation based on fuzzy evaluation and AHP is proposed.The evaluation method can make up for the shortcomings of the conventional evaluation methods in terms of weight determination,evaluation of structural subjectivity and empirical,evaluation of component classification and reliability of evaluation results.An engineering example of structural hollow slab inspection and load test is conducted to analyze the health status of the hollow slab bridge,and the calculation results show that the bridge structure health assessment method based on AHP and fuzzy evaluation method is more scientific and objective,and has certain popularization and application value.(3)The principle,characteristics,scope of application and construction points of several commonly used existing bridge structure strengthening techniques are summarized,and the finite element model is used to analyze the main diseases combined with a hollow slab bridge case,and the reinforcement and transformation plan of sticking the steel plate at the bottom of the beam is drawn up in view of its concrete disease,and the effect of the scheme is verified by stress and deflection.The results show that the bonding steel plate method can significantly improve the carrying capacity and normal service performance of the overall structure of the bridge,and the proposed reinforcement scheme is feasible.