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| Andrade,Maria Luiza de Carvalho; Tassinari,Diego; Dias Junior,Moacir de Souza; Martins,Ricardo Previdente; Rocha,Wellington Willian; Souza,Zélio Resende de. |
| ABSTRACT Planted forests occupy more than 6.5 million ha in Brazil, where harvest and logging operations are performed with increasingly heavier machinery, increasing the risk of soil compaction. Soil compaction can be avoided if soil load bearing capacity is not exceeded, what makes it important to assess both the soil strength and the impact of different operations. The aim of this study was to evaluate the load bearing capacity of some coarse textured soils (two Hapludult and one Haplorthod) in two soil horizons (BA and B), from northeastern Brazil; and to assess the impact of harvest and logging operations performed with harvester and forwarder. Although the Haplorthod presented higher load bearing capacity in both the BA horizon (for the whole... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Harvester; Forwarder; Precompression stress; Soil load bearing capacity.. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542017000200191 |
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| Martins,Paula Cristina Caruana; Dias Junior,Moacir de Souza; Andrade,Maria Luiza de Carvalho; Guimarães,Paulo Tácito Gontijo. |
| The main source of soil structure degradation in coffee plantation is the machinery traffic because these operations may cause soil compaction affecting the crop development. This study aimed to generate the load-bearing capacity models for a Red-Yellow Latosol and to determine through the use of these models the soil susceptibility to compaction of the coffee plantation due to the implantation time and the compaction caused by the machinery traffic on the traffic lines located at the top and bottom of the ground. This study was carried out in the EPAMIG Experimental Farm, located at Três Pontas, MG, in coffee plantations (Coffee arabica L.) with 2, 7, 18 and 33 years of establishment. To obtain the load-bearing capacity models, 12 undisturbed soil samples... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precompression stress; Structure degradation; Soil physics. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542012000400002 |
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| Gubiani,Paulo I.; Reinert,Dalvan J.; Reichert,José M.; Goulart,Rafael Z.; Fontanela,Eracilda. |
| ABSTRACT Soil compression curve (CC) provides parameters to identify soil load-bearing capacity and susceptibility to compaction. An Excel add-in (ACC) incorporating graphical procedures for mathematical models for soil CC description and calculation of parameters was developed. By using the ACC, soil CC can be described by means of the Casagrande method, mathematically operationalized with the van Genuchten equation, with or without restrictions on its parameters, and by Dias Junior and Pierce method in its original form and also modified using the void ratio rather than soil bulk density. The ACC uses a single Excel spreadsheet for input and output data, in addition to a graphical interface and a tool for exporting editable charts. Compared to SAS... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Compressibility; Precompression stress; Load-bearing capacity. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000300603 |
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| Silva,Reginaldo Barboza da; Dias Junior,Moacir de Souza; Iori,Piero; Silva,Francisca Alcivânia de Melo; Folle,Sergio Mauro; Franz,Claudio Alberto Bento; Souza,Zigomar Menezes de. |
| The objective of this work was to develop uni- and multivariate models to predict maximum soil shear strength (τmax) under different normal stresses (σn), water contents (U), and soil managements. The study was carried out in a Rhodic Haplustox under Cerrado (control area) and under no-tillage and conventional tillage systems. Undisturbed soil samples were taken in the 0.00-0.05 m layer and subjected to increasing U and σn, in shear strength tests. The uni- and multivariate models - respectively τmax=10(a+bU) and τmax=10(a+bU+cσn) - were significant in all three soil management systems evaluated and they satisfactorily explain the relationship between U, σn, and τmax. The soil under Cerrado has the highest shear strength (τ) estimated with the univariate... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cohesion limits; Machine-ground interaction; Mechanical resistance; Precompression stress; Soil compaction; Soil physical quality.. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2015000100082 |
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| Martins,Paula Cristina Caruana; Dias Junior,Moacir de Souza; Ajayi,Ayodele Ebenezer; Moreira,Fátima Maria de Souza. |
| Incongruous management techniques have been associated with some significant loss of agricultural land to degradation in many parts of the world. Land degradation results in the alteration of physical, chemical and biological properties of the soil, thereby posing a serious threat to sustainable agricultural development. In this study, our objective is to evaluate the changes in a Cambisol structure under six land use systems using the load bearing capacity model. Sampling was conducted in Amazonas Region, Brazil, in the following land use: a) young secondary forest; b) old secondary forest; c) forest; d) pasture; e) cropping, and f) agroforestry. To obtain the load bearing capacity models the undisturbed soil samples were collected in those land use... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Structure degradation; Bulk density; Precompression stress; Amazonas. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000600006 |
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