||Effect of soil adhesion on tractive performance of single grouser shoe
In this study, the semi-empirical method was adopted for conducting the prediction of vehicle performance. The main parts of this study are similar to the bevameter technique. It is consists of two major parts: direct shearing test and penetration test. Furthermore, in order to predict the vehicle performance, three aspects must be known: the single grouser shoe model including the dimensions and the acted pressure; the shearing model (or the failure type of the soil beneath the grouser shoe) for this single grouser shoe; the soil parameters including the density, the moisture content, the external and internal friction angle, the soil cohesion and adhesion, the sinkage exponent, the modulus kc and kφ. In this study, four different experiments were performed, and the brief introduction will be described as follow. Effect of Soil Adhesion on Tractive Performance of Steel Single Grouser Shoe Using Clay Soil Parameters (Chapter III). The objective of this study is to investigate the relationship of the off-road vehicle’s thrust, running resistance and traction with soil adhesion using a single grouser shoe model and clay soil. In this experiment, the test soil has been changed 10 different moisture content levels from 8.5% to 54% (dry base) for soil parameters measurement. The results indicated that the thrusts, tractions and running resistances of single grouser shoe have the similar trend under all grouser thickness ratios, respectively. However, when the grouser thickness ratio was 0.1, the thrust and traction have the greatest values in all soil adhesion levels when the moisture contents are equivalent. Based on the comparison of the prediction result, the smaller the grouser thickness ratio, the greater the thrust and traction. Effect of Grouser Height on Tractive Performance of Single Grouser Shoe Under Different Moisture Contents Soil (Chapter IV). The purpose of this study is to investigate the grouser height affect on tractive performance of a single grouser shoe under different soil moisture contents. And also, ten different levels moisture content of clay soil were provided in this study. The experimental result showed that the track vehicles with a shorter grouser performed better under a dry soil, and performance with longer grouser tracks was better under higher moisture content soil. Comparing Tractive Performance of Steel and Rubber Single Grouser Shoe under Different Soil Moisture Contents (Chapter V). The objective of this study is to compare tractive performances of steel and rubber single grouser shoes which were changed with the varied soil moisture content. As the same as the previous experiments, ten levels soil moisture contents ranged from 8.58% to 54.36% of clay soil were provided. The experimental results showed that thrust and running resistance of steel single grouser shoe have similar trends to those of rubber single grouser shoe. The thrust of rubber single grouser shoe was always greater than that of steel single grouser shoe with the increase of soil moisture content, and as well as the running resistance. However, traction of rubber single grouser shoe has a different trend to that of steel single grouser shoe. The traction of steel single grouser shoe was always greater than that of rubber single grouser shoe at any given moisture content except at the stage of less than 15% moisture content. From the experimental results, it can be concluded that the steel single grouser shoe performed better than rubber single grouser shoe for the soil used in this study. Effect of Soil Moisture Content on Traction Performance Using Sandy Loam Parameters (Chapter VI). The objective of this study is to investigate the effect of soil moisture content on traction performance of single grouser shoe. Sandy loam soil was used as the test soil in this study. There were five different soil moisture content levels which were changed by adding water into it. The result indicates that the thrust and traction of single grouser shoe with 0. 1 grouser ratio has the maximum value when the moisture content was at the lowest level. However, the maximum value of running resistance of this single grouser shoe emerged when the moisture content was at highest level.
本文 / Laboratory of Crop Production and Ecology Major of Sustainable Resource Sciences Graduate School of Bioresources, Mie University