Dynamic analysis of the load hoisting process

Proposals of two models of a load lifted by cranes have been discussed. Special attention has been paid to the phenomena occurring before detachment of the load from the ground. Stick-slip motion of the load on the foundation has been observed. One of two models presented – the model in the form of a rigid body resting on an elastic foundation has turned out to be more advantageous for the analysis of the lifting process. The results of numerical computations have revealed a phenomenon of solution bifurcation that occurs at a slight change in values of parameters of the model.