INFILTRATION THROUGH T RAFFIC COMPACTED SOIL

Abstract

Infiltration tests were conducted on a sandy loam soil subjected to three levels of compaction using 5, 7,
and 12 tractor passes with a tractor weighing 40 kN. Results indicated that 5 tractor passes induced
average soil bulk density of 1.72 Mgm^-3, hydraulic conductivity of 1.74 x 10-6 cm/s, and penetration
resistance of 479.55 kPa at a moisture content of 14.91 %. The 7 tractor passes produced average bulk
density of 1.81 Mgm^-3, hydraulic conductivity of 1.24 x 10-5 cm/s and penetration resistance of 514.7 kPa
at a moisture content of 12.54 %, while the 12 tractor passes produced average bulk density of 1.91Mgm^-3                                      hydraulic conductivity of 1.69 x 10^-5 cm/s, and penetration resistance of 474.35 kPa, at a moisture
content of 12.11 %. The findings revealed that the number of tractor passes imposed did not significantly
(p> 0.05) influence water infiltration into the soil. However, soil strength increased with compaction
without a corresponding decrease in infiltration. It is concluded that soil type, soil moisture content and
machinery capacity are crucial factors in the infiltration process.