Resistência tênsil e friabilidade de solos coesos

Abstract

Different physical attributes have been used to evaluate soil quality, and the tensile strength (TS) is an indicator of the structural and physical soil quality. Was to evaluate the tensile strength and the friability and its relation with the soil cohesion verifying its efficiency and effectiveness as indicator of structural quality in the presence of cohesive horizons in soils representative of Coastal Boards of the State of Bahia. Soil samples with undisturbed structure were collected for soil bulk density, total porosity, macro, and microporosity determination, and samples with deformed structure for particle size analysis and particle density. Blocks soils were collected, by horizon, for TS and friability determination, which were fragmented in aggregates that were submitted to the electronic penetrometer (model MA - 933 ®), coupled with own device. After TS determination in the aggregates by horizon, their mean was calculated. Soil friability was estimated by the coefficient of variation of the TS measured values, using friability classes for characterization. In relation to the RT, it was observed that the horizons indicated as possibly cohesive of the Yellow Latosol Distrocoeso were BA and Bw1 with values higher than 60 kPa, in the Yellow Argisol Distrocoeso the horizons AB2 and BA with values higher than 100 kPa and in the Argisolo Acinzentado Distrope the horizons BA and BT1 with values greater than 100kPa. As for the friability class, the evaluated horizons of the three soils ranged from friable to very friable.