Aggregate Shape and Tensile Strength Measurement

Autor(es)

Seben, Jr., Getulio de Freitas ^[1] ; Cora, Jose Eduardo ^[2] ; Fernandes, Carolina ^[2] ; Lal, Rattan ^[3]

Afiliação do(s) autor(es)

^[1] Univ Nacl Estadual Sao Paulo, Sao Paulo - Brazil

^[2] Univ Nacl Estadual Sao Paulo, Dept Soil Sci, Sao Paulo - Brazil

^[3] Ohio State Univ, Sch Environm & Nat Resources, Columbus, OH 43210 - USA

• Tipo de documento: Artigo Científico
• Fonte: SOIL SCIENCE; v. 178, n. 6, p. 301-307, JUN 2013.
• Citações Web of Science: 4

Resumo

Tensile strength (TS) of soil aggregates is an important indicator of soil quality. However, TS varies with aggregate shape. Thus, the objective of this study was to quantify the influence of aggregate shape on TS and propose a shape standardization protocol to increase accuracy in the measurement of TS. The latter was determined on 7,560 aggregates divided into three shapes, (i) irregular shape (IS), (ii) spherical shape (SS), and (iii) flat surface (FS), while preserving the inherent structure of the aggregate. The aggregates with IS had a larger range in the TS (306 kPa) because of the shape variability when compared with SS (238 kPa) and FS (129 kPa). The TS determined in aggregates with FS had smaller coefficient of variation (46%) in comparison with those of IS (70%) and SS (66%), indicating that the aggregate uniformity reduced the influence of shape on the TS. A smaller force (42.12 kPa) was needed to rupture aggregates with FS than IS (58.43 kPa) and SS (56.89 kPa) because of better force distribution in causing the tensile stress. The use of aggregates with the FS enables an accurate assessment of TS in relation to a wide range of management treatments. (AU)

• Processo FAPESP: 08/52560-1 - Resistencia tensil de agregados de um latossolo vermelho eutroferrico sob diferentes sequencias de culturas em semeadura direta.
• Beneficiário: Getulio de Freitas Seben Junior
• Linha de fomento: Bolsas no Brasil - Mestrado