Nonlinear Dynamic Analysis Of Crawler Crane Boom

The crawler crane boom is a complex lattice structure,which has a large slendernessratio.It is a flexible body that bears both lateral loads and axial loads.It is the basis to accurate dynamic analysis of the crawler crane truss boom for the safety and normal operation of the crane.With the continuous development of science and technology,the lifting performance of cranes has been continuously improved,the lighter weight of structures has been used more extensively,and the safety requirements in the course of operations have become increasingly stringent.Accurate and efficient calculation and analysis methods are the main research contents of crane design at present.In the past,static analysis and dynamic analysis of rigid body can not meet the demand for accurate calculation and analysis of parts with large flexibility.Under the influence of the second-order effect,the flexible multi-body system dynamics method is used to analyze the amplitude of the truss boom in this paper.Based on finite element theory,a cubic polynomial interpolation function is applied to the displacement fields of two-node Euler-Bernoulli beam element,and the element shape function is obtained through the initial condition and Kirchhoff assumption.By using the method of flexible multi-body system dynamics,the motion state of beam element is described,considering the rigid motion and elastic deformation of flexible beam element,the interaction and coupling between beam element are deduced under the local coordinate system considering the effect of the second order equation of motion.The two-node beam element is used to compare the bottom section,standard section and top section of truss boom system respectively,considering the truss boom under the influence of the second-order effect,through the theory of kinematics and dynamics analysis of flexible body displacement of flexible units kinetic energy and potential energy,using Lagrange equation based on dynamic equation of servo coordinate method.The dynamic equation of the flexible beam element in the whole coordinate system is derived by the relation between the coordinate system and the integral coordinate system.The 750 ton crawler crane truss-type boom is selected as the research object,and the typical boom hoisting cases,are selected for analysis.The dynamics equation is solved by using Simulink,and through the ADAMS dynamics simulation was carried out on the boom,contrast truss boom transient response in the luffing process and the second-order effect on the impact of the displacement and speed.The calculation results show that the displacement and deformation of the large slenderness ratio truss boom are basically consistent with thesimulation results under the second-order effects,indicating the validity and rationality of the numerical calculation method.