The Key Technology For The Structral Dynamic And Static Analysis Of A Lattice Arm Breaker Bridge-inspection Vehicle

With the rapid development of China's economic construction, the traffic also grow fast, large trucks and overweight vehicles are increasing day by day, then the fact leads to the damage to roads and bridges. To ensure the normal use of the bridges, timely maintenance is badly needed. Bridge-inspection vehicle is prepared to fit for the development of science advancement and the needs of the market. Bridge-inspection vehicle is a special equipment for bridge's inspect and maintenance, it offers platform which is fastened to the automobile chassis to inspectors to move to the right place safely and rapidly.The research topic, taking the Bridge-inspection vehicle relate to the"Eleventh Five-Year"science and technology support projects as its background, the previous analysis of Bridge-inspection vehicle usually aim at its stiffness, strength and stability check at stationary state, ignore the complicated dynamic effects resulting from the mechanism kinematics, the reason lies in it is too difficult to create a suitable model to describe the dynamic problem.In order to solve the problem mentioned above, we should make clear the dynamic characteristic firstly, through the establishment of full size finite element model of beam and truss system. After the dynamic analysis, we got the dynamic characteristic of bridge-inspection vehicle, analysis the characteristic of its modes and reason, sets up a good foundation for subsequent research.Take the result of the full size finite element model of bridge-inspection vehicle as reference, transform the lattice jib into an equivalent beam. After dynamic analysis, we get the dynamic characteristic to evaluate the rationality of the equivalent method. The result demonstrates that the amount of free degree and elements are reduced greatly, and the accuracy is satisfactory. This method make clear the stiffness criteria of the structure of the bridge-inspection car, provides a reference for engineering, and a foundation is established for further dynamic analysis.The equivalent model provides an possible analysis of original system with a large amount of element and high free degrees in mechanisms dynamics. Through adequate modeling theory, a simple and direct dynamics equation is well established, solutions of which are clues to the force of the structure in different position during the erection and of valuable reference to practical projects.In response to the features of the structure, the weight of the jib will seriously impede the work performance, so the structure is optimized with the lightest weight of the structure as the object, with the strength, rigidity and stability as the restraint, with the cross-section of the truss structure as the design variables, and base on the application of the ANSYS finite element analysis software, made to meet the use requirements and reduce the cost of manufacturing.