The Problems of Dynamics of Wheeled Vehicles with Flow Able Building Cargo

摘要

The issues of the dynamics of the wheeled vehicles transporting free-flowing construction materials (concrete, mortar, bitumen and other construction mixes) are considered. It is proved that for the purpose of safety, the oscillations of free-flowing construction materials during the vehicle movement should be taken into account. So, in general, free-flowing construction materials are non-Newtonian fluids, i.e. their flow rheograms are non-linear. If, however, we take into account the fact that during the oscillations the deformations of non-Newtonian fluids do not occur in one plane but they do in all four coordinate planes, then the hysteresis behaviour of these rheograms is natural, which is confirmed experimentally. Then the area of the hysteresis loop allows us to perform the linearization of the problem when calculating the oscillations of the dynamic system "road-vehicle-free-flowing construction materials". The oscillation analysis methods of the wheeled vehicles with free-flowing construction materials both in transversal and longitudinal planes have been developed, as well as the recommendations for increasing the stability of the wheeled vehicles against rollover and for reducing structural loads in transient motion mode of the vehicle have been given. The research allows us to consider the dynamics of the wheeled vehicles both with free flowing and solid construction materials in general. What is more, the case with a free-flowing construction material is comprehensive and the one with a solid material is specific. The developed methodology made it possible to implement a number of design solutions which improve the structural safety of the wheeled vehicles transporting free-flowing construction materials.