A Study On Birdge Reinforcement By Bonding Steel Plate (Box) With Analysis Of The Ultimate Bearing Capacity

Steel Box Strengthening Method is a new reinforcement method which based on thereinforcement with bonding steel plate. Steel Box Strengthening Method is a steelbox-concrete composite structure. Filled the micro expansion concrete in the tension box inorder to reduce distortional warping of empty steel box and improve the stability of thestructure. Compared with ordinary stick steel strengthening methods, Steel Box StrengtheningMethod has some positive benefits, such as high stiffness, little deformation and excellentstability, But as a result of this reinforcement method were late, its application is less both athome and abroad. This paper mainly studied the application of steel reinforcement method inbridge reinforcement and the ultimate bearing capacity of Bridges.Based on the strengthen of the Huang river bridge of the S309, this paper systematicallyresearched the application of the Steel Box Strengthening Method in reinforcement of thetwo-way arch bridge. This paper completed on the following aspects:(1) Introduced the features, the range of application and construction technology Ofreinforcement with bonding steel plate in detail. Combined with the bridge reinforcementspecification, this paper analyzes the bending resistance and resisting shear of bridge afterapplied Steel Box Strengthening Method.(2) Studied the distinction and contact of Steel Box Strengthening Method and pastingsteel plate reinforced method. And also studied its stress mechanism, applicable scope,strengthening characteristic. Using steel concrete composite structure theory deduced thedesign formulas of bending resistance and resisting shear.(3) Analyzed the damage of HuangShu river bridge and its mechanism. Assessed thestrengthening effects of steel box on HuangShui River Bridge which strengthened the mainarch rib by applied Steel Box Strengthening Method. This paper also combined the numericalcalculation and experimental results to evaluate the reinforcement effect of bridge.(4) Illustrated the influence factors of bearing capacity of Bridges and established anevanescent mode of strength of materials which the loadingof shrinkage and creep of concrete and fatigue loading. combined with the Code for RatingBridges, this paper analyzed the influence of Overload operation to the safety of the bridgebearing capacity and the attenuation law of bearing capacity. By analyzing the data inexistence and the interrelated criterion, this paper find out that the qualitative the influence ofreinforcement corrosion, crack and concrete carbonization to the bearing capacity of bridgestructure.(5) Using finite element software Midas/civil,analyzed the influence of the materialnonlinear to ultimate bearing capacity of arch rib, using elastic-plastic analysis method to calculate the ultimate bearing capacity of bridgeThe research results of this paper：the Steel Box Strengthening Method is a kind ofeffective reinforcement methods When Bridges lack of flexural bearing capacity. Afterapplied the method, the bearing capacity of hyperbolic arch bridge and arch rib is improvedgreatly. it is feasible the to using the theory of Steel concrete composite structure tocalculate the bearing capacity of steel reinforced components. Nonlinearity materials have asignificant impact on the ultimate bearing capacity of the beam strengthened by steel box.