Structural Design And Analysis For The Bridge Inspection Vehicle Which Walks Along The Rail Under The Bridge

Abstract:China’s high-speed railway has a large proportion of bridges, especially elevated long bridges. The new-type railway has a narrowed down deck, which has no side walk on neither of the sides. And the it also has characteristics like high operating frequency, strong closure, and limited time for test and maintenance. On one side these factors have caused the bridge’s maintenance problems become severer, on the other side they have led to that the existing bridge maintenance equipment and operating methods cannot adapt to the needs of the current overhaul of the high-speed railway bridges. Thus, there is a great need to develop maintenance equipments that comes from China’s high-speed rail technology.After surveying all types of bridge maintenance equipment at home and abroad, and the task of the railway bridge maintenance operations, this paper put forward structural design and analysis for a bridge inspection vehicle based on the special form of the structure of the high-speed railway bridges, which walks along the rail under the bridge and is applicable to the railway viaducts. What’s more, the solutions were demonstrated and analyzed.Based on the mechanical design and virtual prototyping technology, the following research was carried out in this paper:(1) Established the structure design of the vehicle, including the walking agencies, platform’s structure, rotary device, configuration weight agencies, power equipment, such as the design and selection content.(2) Used the Autodesk Inventor to build a digital prototype model for statics and dynamics studies.(3) Used the ANSYS Workbench to do the structure static analysis for the key components, and checked their structural strength and stiffness, obtained optimization program.(4) Made the modal analysis for its truss structure to find out the vibration characteristics of the structure, and provided a reliable theoretical basis for the prevention resonance and resistance to fatigue failure.(5) Analyzed the inspection vehicle’s structural dynamics and tested the vehicle’s working performance by using the motion simulation module of the Autodesk Inventor.The results of design and analysis showed that:the structural design functions of the vehicle effectively met the requirements of the maintenance tasks. The mechanics of the vehicle’s key parts were designed to achieve the relevant provisions of the standard. According to the natural vibration characteristics of the structure, the risk of resonance in the using process would not occur. The vehicle’s dynamic performance met the design requirements and the risk of the vehicle overturning would not occur. The design and selection of the inspection vehicle structure was rational.