Influência de estados de compactação em parâmetros de cisalhamento em um latossolo sob sistema plantio direto.

Abstract

This work objective was to study shear strength tension in four compression levels through a road roller in a dystroferic red oxissol using soybean and corn culture in each treatment. The study took place in Cascavel, State of Paraná, Brazil. The treatment were as follow: T0 = no additional compactation; T1 = once over; T3 = three times over; and T5 = compacted 5 times. To determine shear strength tension parameters maximum shear strength ( ), cohesion (c), and internal attrition angle Sheargrap was used with normal tension levels ( n ) of 5, 10 e 15 kPa turning the cutting device until soil breaks lose. Three repetitions were performed in each culture and experimental units. Three for both corn and soy cultures in a depth of 0-0,10 and 0,10-0,20 m. Based on the results, we concluded that shear strength tension, evaluated at 0,10 a 0,20 m depth, was influenced by compression levels in the corn and soy cultures, whereas in the 0- 0,10 m depth there was no significant difference. Resistance values to shear strength tension by depth in soybean and corn culture showed no dissimilarity.