The Force Analysis And Reinforcement Research Of The Semi-Rigid Connected Rigid-Frame Arch Bridge

In recent years, many scholars have analyzed the space performance of rigid-frame arch bridge, but in order for simple calculation, they often adopt the pin joints or rigid joints. However, it should be the semi-rigid connection. In this paper, it studies the semi-rigid connection of the ribbed bride, and the reinforcement of the horizontal ties and the slightly curved board. The main research is as follows:(1) To analyze the ribbed beam joints by building mode through Ansys, study the stress character of the connected ribbed beams after the connected joints are damaged, and to draw an M-θr curves. It shows that the connection of the ribbed beam a semi-rigid and the connection stiffness is lowered accompanying the weld joint is damaged.(2) To find the law of the transverse distribution coefficient of the rigid arch bridge of different cross beam rigidity or ribbed beam coupling stiffness based on the standard atlas of the rigid arch bridge through Ansys. The results show that the increase of the cross tie beam stiffness should be matched with the joint stiffness of the ribbed beam. The transverse distribution coefficient will not change if only by improving the cross beam rigidity.(3)To find out how the connection stiffness of the ribbed beam will affect the bridge’s inner force, dynamic property and stability, how the joint stiffness will decrease and how the structure performance will change after the connection of the ribbed beam is damaged. The result shows that the ribbed beam connection stiffness is a greater impact on the structure performance, and thus engineer should pay great attention to the ribbed beam connection.(4) Take a damaged rigid arch bridge for example, to put forward the connection stiffness before reinforcement, and to calculate the property of the deflection and natural vibration, and compare it with the testing result and thus to test the reasonability of the damaged bridge mode. To study the lateral connection method according to the bridge’s force analysis and the property of the disease, and to analyze the rationality and effectiveness of cross beam reinforcement scheme throng the theoretical calculation and the test result after reinforcement.(5) Through the analysis of the force performance of the slightly curved board under different constraints, it shows that when the arch rib enhance the lateral constraint of the slightly curved board, its arch effect will be obvious, and the bottom stress ability of the curved board will be lowered. Through the real test and theoretical analysis, it shows that the reinforcement method of slightly curved board by curved steel will not only improve the lateral constraints but also will form a unitized construction between slightly curved board and structural steel, which will improve the vertical stiffness and its stress performance.The above analysis of the rib bridge’s semi-rigid connection of the rigid arch bridge and the research of reinforcement method of the lateral beam and slightly curved board is a reference for the analysis and reinforcement of the similar bridge.