The Local Stress In The Box Girder's Main Web Caused By The Pressure Of Trolley

The main web has large local stress caused by the pressure of trolley, the large local stress value directly affected the ascertaining of the rail type and the geometry parameter of the box girder. The methods used in the crane design are usually based on classical mechanics and mathematics, such as the method combined theory with experience, method of analogue, method of intuition and other traditional methods. The former researches about the local stress are mainly about making experiment and theory calculation, its results are usually conservative and inaccurate. Because of the restriction of economical factor sand experiment conditions, it is unpractical to choose a series of cranes to research the relationship between geometry parameter and local stress. As the development of technology, advanced design theories and methods emerge, which makes the research about this problem be solved by computer simulation. Aimed at the above problem, this paper will use ANSYS, a big finite software , to build a model to analyze the local stress in the main web, at the same time, carry out theory research by using elasticity mechanics, contact mechanics and elastic-ground beam theory.The main works in this paper are as follows: assume that the local stress in the main web is caused by the contact methods, which involve the wheel-rail contact and the contact between the rail and main girder. Then build a contact analysis model to simulate the practical situation by combining the Hertz contact theory with the finite software ANSYS. The analysis model will do research to explain the relationship between the local stress and the different situations, such as different pressure of trolley, rail second moment of area and box girder section geometry parameters, making some conclusion. Carry out theory research by using elasticity mechanics, contact mechanics and elastic-ground beam theory and simplify the rail's support from box girder as the support from the main web. On the premises of the simplification, for one thing, building a uniform load model to get a local stress calculation formula, for another thing, view the analysis model as the Winkler elastic-ground model and finally get a calculation formula by theory analysis and calculation. At last, compare and analyze the results from the finite analysis,Winkler formula and empirical formula...