Study On The Possibility Of Using Other Method Than Sedimentation Method To Determine Particle Size Distribution Of Organic Soil

Abstract

Approximately 20% of Indonesian land area (39 million hectares) is organic soil, where a mat of living vegetation on the surface with a layer of saturated peat beneath it. Since the saturated peat beneath the mat is often weaker than the mat, a number of problems of trafficability and mobility arise due to this kind of soil. Mechanical land preparations for agricultural farming also almost failed in several locations in Indonesia. Satisfactory analysis of the tractive performance parameters (rolling resistance, drawbar pull and tractive efficiency) of off-road vehicles, especially farm machinery, depends on accurate prediction of the forces between the soil and the tractive elements of the vehicles. Off-road vehicles are now expected to attain a high level of energy efficiency and not to cause undue damage to the environment, especially to the soil. Establishment of functional relationship of pressure-sinkage becomes one of fundamental tasks that may be improving the tractive performance of off-road vehicles. Soil physical and mechanical properties may govern the sinkage as well as load and dimensional contact area properties. Cohesion and friction as soil mechanical parameters were also indicated in prior empirical models to predict the sinkage of off-road vehicles, e.g. Bekker’s equation and Reece’s equation (Wong, 2001). These parameters are responsible to the strength properties of soil which considered may influence the sinkage-pressure relationship. However, according to the previous research, several soil parameters (particle size distribution, moisture content, density, etc.) also considered being the dependent factors which influence the strength properties of soil and indirectly may role the sinkage-pressure relationship (Saulia et al, 2007). ...