Research On The Adhesion Property Of High-speed Track On Soft Ground And Optimization Of Track Shoe

Tracked vehicles always run on soft ground at a rapid speed, of which the heavy groundpressure, complicated running gear and many changes of soft soil condition restrict theimprovement of its passing ability. Tracked vehicles’ ground adhesion property, whichdecides the vehicle’ maximum tractive force, is an important indicator of the vehicle’s passingability on soft ground. This thesis will study tracked vehicles’ adhesion property from theaspects of soil mechanics characteristics, vehicle design and driving parameters, and establishmathematic model of track shoe-ground adhesion, furthermore, it aims to carry on thedynamic experiment of actual track shoe adhesion load and model test of grouser effect.Besides, based on the track shoe-ground adhesiveness model, the thesis author deduces thevehicle track-ground adhesion model and proposes several track shoe optimization schemeson different typical grounds.The present thesis will analyze tracked vehicles’ adhesive characteristics from twoperspectives as ground and vehicles. Three kinds of typical soil samples, that is, fluctuantroad, plateau road and river shoal road are taken as the research objects to implement soiltests to get the soil mechanics characteristics parameters under different moisture contents.What’s more, a new soil shear strength formula is amended on the basis of moisture contentand shear rate. Ultimately, the track-ground adhesion model is established with thecombination of the new soil shear strength formula and Rankine passive soil pressure theory,with the shapes of track shoe grouser into account.On the foundation of elasticity model and Mohr-Coulomb model, a soil finite elementmodel is established and track-ground adhesion model is testified through finite elementsimulation. In addition, this thesis examines and amends the track shoe-ground adhesionmathematical model by setting up the soil-box experiment system of track shoe adhesion andcarrying on the dynamic test of actual track shoe adhesion load and track shoe adhesionmodel test.This thesis will deduce the track-ground adhesion model on the basis of single trackshoe-ground adhesion model, and establish multi-body dynamics simulation model oftracked vehicle’s adhesive forces by taking advantage of LMS Virtual.Lab Motion software. The simulation is conducted concerning the tension force of track tensioner. Finally, itestablishes track-ground adhesiveness model based on the theoretical deduction andsimulation result which takes into factors consideration, such as the distribution of groundforce, travel speed, track shoe distance and tension force of the track tensioner.Taking improvement of tracked vehicles’ motion performance on the soft ground intoconsideration, the present thesis aims to optimize track shoe to improve its largest pothooktractive force on certain traveling conditions. Besides, the optimized constraint conditionswill cap the tracked vehicle’s driving resistance, namely the vehicle’s power consumption.Suitable and typical tracked vehicles’ track shoe construction parameters will be obtained byselecting four design variables, which are track shoe distance, track grouser height, trackgrouser thickness and the inclined angle of track grouser, optimizing the combined featuresof three typical ground conditions and demands of vehicle’s driving conditions respectively.