Pneumático de tração e estrutura diagonal: tensões verticais em tanque de solo.

Abstract

The performance of the tire affected soil compaction, tractor traction and sliding. A study of the soil vertical stress behavior submitted to an agricultural tire, under application of four magnitudes of loads, was carried out on a Red Latosol. This study aimed to estimate the vertical stress occurred into the soil mass, using pressure cells, simulating the behavior of the interior of the ground submitted to wheeled tractor traffic. It was studied an Good-Year tire with diagonal construction structure, model Dyna Torque II, dimensions specification 23.1-30, applying two kinds of tire inflation pressure, called low and high pressures, as follows: 7 psi (48.3 KPa) and 17 psi (117.2 KPa). It was also used two kinds of Red Latosol: a clayed Red Latosol with 48.5% of clay and 45.0% of sand, soil dry bulk density of 1.20 g.cm-3 and a sandy one, with 77.0% of sand, 21.5% of clay, soil dry bulk density of 1.40 g.cm-3. To accomplish this experiment with two soil types and under different conditions it was used equipment for static test named soil bin with hydraulic device to apply the designed loads. The used soil bin has the dimensions of 2.0 x 1.0 x 0.8 meters. This research applied the hydraulic presser method to put charges over the tire. The experimental design used was a 2x2x4 factorial trial with four replicates. Results showed that the pressure cells installed into the soil bin presented decrescent stress starting from the ground surface. Also showed that the value of the first cell, installed to a 10 cm depth, was always near the tire inflation pressure value.