EFFICIENT SIMULATOR OF GROUND LEVELING WITH A BULLDOZER: TOWARD REAL-TIME FEEDBACK AND AUTOMATIC OPERATION

Abstract

 This study aims at developing an efficient simulator of ground leveling operation with a bulldozer. First, a series of field experiments and Discrete Element simulations have been conducted to find the following three mechanisms: (a) local soil swelling movement occurs in front of the blade at the initial stage of the leveling, (b) at later stage shear plane is formed in the soil mound and the soil above the plane is pushed out as a rigid mass, and (c) the pushed mass causes the subsequent slope failure at the far side slope of the mound. Then, based on the above observation, we construct a simple algorithm to model the above deformation mechanisms, in which the soil mound is described as a collection of soil columns, and the height of the columns are evolved by (a) the local swelling deformation, (b) the rigid motion of soils above the shear plane computed by Coulomb earth pressure theory, and (c) the slope modification modeled by diffusion equation, respectively. The proposed model is verified by a theoretical earth pressure problem, and validated by comparing to both the DEM simulations and the field experiments.