Research On The Modeling Of All Terrain Crane With Super-lift System Under Catenarian Effect

The super-lift, a kind of supporting device installed on crane boom, is used to improve the carrying capacity of telescopic boom of all terrain crane in luffing plane and rotation plane. It can improve the force situation of crane jib by means of a triangle stable structure with super-lift pole and crane boom formed by preloading super-lift rope. The study is very necessary because the super-lift technology of all terrain crane is relatively mature abroad but rare domestically, knowing nothing about the influencing mechanism of the property of super-lift rope; meanwhile, detailed discussions and research achievements have not been seen in various literatures.Catenary theory is applied into the research of super-lift device on all terrain crane based on the catenarian effect of super-lift rope. The calculative model of super-lift device is built according to the theory and the influencing mechanism that super-lift device acts on boom is studied systematically and penetratingly. The main content of the paper includes the following aspects:1) An in-depth study of super-lift device is made. The catenarian effect of super-lift rope is considered in view of the defects caused by super-lift rope being simplified as bar element; the computational model of super-lift rope is built on the basis of catenary theory and the model simplification and force analysis of super-lift rope by the basic assumptions of catenary theory.2) A study of super-lift device under finite element model simplification and calculation. Considering the geometrically nonlinear large deformation, the finite element model of super-lift rope is built by using beam elements with little bending stiffness and nonlinear calculate is obtained. And then the FEA result and the catenary equation is comparatively analyzed, the impact that model parameter acts on the result is discussed and the feasibility of the model is validated by examples.3) The relationship among super-lift device rope, pre-tightening force and pre-tightening angle is expounded. By examples, the quantitatively curves of the influence that super-lift guyed rope geometric shape act on boom and the stress of super-lift guy rope are obtained under the evaluational criterion of global stress and local stress of pin hole, the influence law under the quantitative result is discussed.The results show that the catenary effect of super-lift guy rope profoundly impacts on the property of boom, as well as the achievements in this paper have been used in the actual project cooperated with company---TZQAY500T, the research and development of all-terrain crane. It provides an important theoretical reference for the design of all-terrain crane and has a certain general significance and practical value in the field of construction crane.