Influência da pressão interna dos pneus e da velocidade nos parâmetros operacionais de um trator agrícola e nas propriedades físicas do solo

• Autor(a) principal: Feitosa, Jardênia Rodrigues
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3675
• topic: Tratores agrícolas; Maquinas agrícolas - Tração; Solos - Compactação; Solos - Erosão; Agricultural tractors; Agricultural machinery - Traction; Soil - Compression; Soil - Erosion; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA::MAQUINAS E IMPLEMENTOS AGRICOLAS

Easier to acquire tractors has contributed to expand the use of these machines in Brazilian farms bringing many benefits to the agricultural sector. Although its use ensures greater efficiency and profitability of agricultural activities, the traffic of tractors cause changes in soil physical quality and can trigger processes of compaction and erosion. Changes in density, porosity and soil penetration resistance are indicative of soil compaction caused by the application of pressures at the same during machinery traffic. Factors such as the weight distribution of the tractor, internal tire pressure, the contact area between the tire and the ground, speed and traffic intensity influence the compaction process and affect the operating performance of the tractor. Given this, the aim with this study was to evaluate the influence of the change of the internal pressure of the tires and the travel speed of a MFWD farm tractor in the physical properties of soil and the parameters kinematics advance, slip of wheelsets, area of tire-soil contact and pressure applied to the soil surface by the tractor. The experiment and other determinations were performed at the Federal University of Viçosa, MG, using a MFWD farm tractor equipped with diagonal tires construction. The areas of contact between the tires and the ground and the pressures applied to the soil by tractor were determined under static conditions, when the tires were inflated to the pressures 82.74, 96.53 and 110.32 kPa. For the evaluation of change in physical properties of the soil caused by traffic, a field experiment was installed in which three combinations of internal pressure applied to the front and rear tires were evaluated (P1: (82.74, 96.53 kPa), P2: (96.53, 110.32 kPa), P3: (110.32, 124.11 kPa)) and three speeds (V1: 4, 27 km h -1 , V2: 5.43 km h -1 , V3 7.31 km h -1 ), determining the bulk density, porosity and resistance soil penetration, which were used as parameters for evaluation of compaction. Still the kinematics advance and the slip of wheelsets of the tractor were determined. The results demonstrated that the combination of pressure P3 led to obtain a value considered ideal for the kinematics advance of the tractor, and that different combinations of pressures and speeds did not significantly alter the slip of wheelsets. The reduction of the internal pressure of the tires 124.11 to 82.74 kPa increased by 25% the area of tire-soil contact of the rear tires, and reduced by 24% the average contact pressure applied to the soil for the same. Soil bulk density and total porosity were affected by tractor traffic studied with the greatest changes in porosity caused by the application of the combination of pressure P3 (110.32; 124.11 kPa) and V2 speed (5.43 km -1 ), and observed with greater intensity in the range from 0.0 to 0.10 m depth.