Study On The Key Technologies Of Mechanism And Precautionary Measures For Nanyang-Xiping Highway Bridge Disease

With the rapid development of highway construction in our country, there are more and more large-span bridges, but more and more early diseases of the pavements appeared in many bridges due to design, construction, overload and climate. The phenomenon of bridge pavement early diseases becomes more and more popular. It not only hinders the normal traffic and affects the beauty and service quality, but also caused many traffic accidents and tremendous economic losses. The failure of bridge deck pavement has become one of the main diseases of highway bridges.Though many research works are carried out home and abroad, and there are many process methods and research findings about bridge deck pavement, many key problems or difficulties have not been solved. Based on the research background and sponsored by Scientific and Technological Project of Henan Province (No:05-02), this dissertation aims to obtain the effect factors of structural mechanical for bridge deck pavement through theoretical analysis. Then through finite element numerical analysis, the stress response of different pavement combination under wheel load are investigated, then mix design and performance test of modified asphalt compound are carried on, the asphalt compound with better anti-wheel-rutting performance, better resistance to moisture and better fatigue performance are acquired. Then, the adhesive strength properties of the four types of the water proof adhesive materials are compared through direct shear tests and tensile tests and the anti-freeze-thaw breakage characteristics are studied. In the end, the mechanisms of single slab bearing disease for simply supported beam bridges are inquired into through finite element theoretical analysis and some protection methods are brought forward. The results of the paper are adopted in the construction application of Wan-ping Highway, the construction period are shortened substantially, the construction quality are improved apparently, the cost are reduced and conspicuous economic and societal benefits are gained.In this dissertation, following aspects are studied theoretically, numerically and experimentally, and some results are achieved:(1) The effect factors of structural mechanical for bridge deck pavement are abtained through theoretical analysis, then the stress response of different pavement combination under wheel load are investigated, the relationship between the stresses of deck pavement and thickness of top and bottom part deck and modulus of elasticity, research results are very important to Chongyang Reservoir bridge, it also provides theory evidence for the design and construction of concrete bridge pavement.(2) The mix design and performance test of modified asphalt compound of bridge deck pavement are carried out, and after the graduation preference, the optimal graduation of top and bottom layers for bridge deck pavement are obtained, the asphalt compound with better anti-wheel-rutting performance, better resistance to moisture and better fatigue performance are acquired.(3) The actual stress conditions of the water proof adhesive layer of bridge deck pavement are modeled, the influence of different adhesion Consumption, temperature, shear speed and freeze-thaw circulation on shear strength of adhesive layer are studied firstly. Then the adhesive strength properties of the four types of the water proof adhesive materials are compared through tensile tests. In the end the anti-freeze-thaw breakage characteristics are studied.(4) Based on the introduction of essential features of single slab bearing disease, the reasons are analyzed. Through finite element preliminary analysis, the lateral distribution of load is analyzed. Then through the numerical solid analysis, the analysis and comparison of different reinforcement schemes are carried through, the theoretical basis for disease control of single slab bearing are indicated. In the end, some precautionary measures are made for reference to department of design, construction and administration so that single slab bearing disease of simply supported girder bridge can be controlled radically.