scholarly journals Experimental evaluation of the classical and alternative consolidation theories in predicting the volumetric change of contaminated and non-contaminated soil

2021 ◽  
Vol 44 (4) ◽  
pp. 1-10
Author(s):  
Moisés Lemos ◽  
Lucas Guimarães ◽  
André Cavalcante
Keyword(s):  
Hydraulic Conductivity ◽  
Alternative Interpretation ◽  
Saturated Hydraulic Conductivity ◽  
Southeastern Brazil ◽  
Collapsible Soil ◽  
Collapse Potential ◽  
Collapsible Soils ◽  
Total Settlement ◽  
Consolidation Coefficient ◽  
Guelph Permeameter

Several regions in Brazil and the world suffer from the presence of collapsible soils. The development of theories for understanding the phenomenon is significant because the increase of water content is associated with several reasons (e.g., precipitation, rupture of sewage, and water systems). Although some theories explain the behavior of various types of soils, they fail to explain collapsible and structured soils. In this research, an alternative interpretation of the consolidation theory is verified and calibrated for collapsible soil. The alternative model was applied to experimental data from a latosol from southeastern Brazil, and comparisons with the classical theory showed a difference in the saturated hydraulic conductivity of around 100 times. The observation showed promising results compared with the saturated hydraulic conductivity of the field (Guelph Permeameter). Furthermore, consolidation tests verified the collapse potential, the variation of consolidation coefficient and saturated hydraulic conductivity, and the total settlement prevision due to the presence of bleach and washing powder.

AN EVALUATION OF THE GUELPH PERMEAMETER FOR MEASURING SATURATED HYDRAULIC CONDUCTIVITY

1990 ◽  
Vol 33 (4) ◽  
pp. 1179-1184 ◽  
Author(s):  
J. Gallichand ◽  
C. A. Madramootoo ◽  
P. Emight ◽  
S. F. Barrington
Keyword(s):  
Hydraulic Conductivity ◽  
Saturated Hydraulic Conductivity ◽  
Guelph Permeameter

scholarly journals CONDUTIVIDADE HIDRÁULICA DO SOLO SATURADO NA ZONA VADOSA IN SITU E EM LABORATÓRIO

Irriga ◽  
2009 ◽  
Vol 14 (3) ◽  
pp. 413-422
Author(s):  
Rodrigo Trevisan ◽  
Luiz Felipe Salemi ◽  
Jorge Marcus de Moraes ◽  
Julio Cesar Martins de Oliveira
Keyword(s):  
Hydraulic Conductivity ◽  
Sao Paulo ◽  
Laboratory Method ◽  
Saturated Hydraulic Conductivity ◽  
Fundamental Parameter ◽  
São Paulo ◽  
Advantages And Disadvantages ◽  
Constant Head ◽  
Guelph Permeameter

 CONDUTIVIDADE HIDRÁULICA DO SOLO SATURADO NA ZONA VADOSA IN SITU E EM LABORATÓRIO  Rodrigo Trevisan1; Luiz Felippe Salemi1;  Jorge Marcos de Moraes1;  Júlio Cesar Martins de Oliveira(4)(1)Laboratório de Ecologia Isotópica, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP,  e-mail: [email protected] (4)Laboratório de Física de Solos, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP  1 RESUMO A condutividade hidráulica do solo é uma propriedade fundamental na determinação da dinâmica da água e de solutos em solos saturados e não - saturados, sendo útil na resolução de problemas relacionados à preservação do meio ambiente, da agricultura e dos recursos hídricos. Muitos métodos são empregados para a sua determinação em solos saturados, tanto em campo como em laboratório, cada um com suas vantagens e desvantagens. Nesse contexto, o objetivo do presente trabalho foi o de comparar um método de campo, o método do permeâmetro de carga constante (“Permeâmetro Guelph”), e um método de laboratório, também de carga constante usando amostras indeformadas de solo, em um solo classificado como Latossolo Vermelho Escuro, da região de Piracicaba - SP. Conclui-se que o método de campo e o método de laboratório não podem ser considerados diferentes. UNITERMOS: permeabilidade; zona não saturada; latossolo; permeâmetro guelph.  TREVISAN, R.; SALEMI, L. F.; MORAES, J. M.; OLIVEIRA, J. C. M. THE SATURATED HYDRAULIC CONDUCTIVITY IN THE VADOSE ZONE IN SITU AND IN LABORATORY  2 ABSTRACT The saturated hydraulic conductivity of the soil is a fundamental parameter to determine  water and solutes dynamics in the soil, and it is useful  to resolve problems related to environmental, agricultural and water resources preservation. Many methods are used for its determination, in field and in the laboratory, each one with its advantages and disadvantages. The main objective of the present work was to compare a field method, using a constant head permeameter (“Guelph Permeameter”), to a laboratory method also employing a constant head in undisturbed samples in a soil classified as dark red Latosol (Oxisol) in the area ofPiracicaba. The results show, through statistical analysis, that the values obtained by the field and laboratory methods cannot be considered different. KEYWORDS: permeability; unsaturated zone; oxisol;guelph permeameter.

A constant-head well permeameter method for measuring field-saturated hydraulic conductivity above an impermeable layer

2004 ◽  
Vol 84 (3) ◽  
pp. 255-264 ◽  
Author(s):  
Masaki Hayashi ◽  
William L. Quinton
Keyword(s):  
Hydraulic Conductivity ◽  
Weighted Average ◽  
Saturated Hydraulic Conductivity ◽  
Shape Factors ◽  
Promising Tool ◽  
Northern Regions ◽  
Measuring Field ◽  
Impermeable Layer ◽  
Constant Head ◽  
Guelph Permeameter

Hydrologic understanding of mountainous and northern regions of Canada is poor owing to the lack of critical field data such as hydraulic conductivity. A portable field instrument, the Guelph permeameter (GP), is a promising tool for measuring field-saturated hydraulic conductivity in remote watersheds inaccessible by motorized vehicles. In order to extend the applicability of the GP method to relatively thin soils underlain by impermeable bedrock or permafrost, a new set of shape factors was determined by numerical simulation. The new shape factors gave accurate values of field-saturated hydraulic conductivity when tested in the laboratory. The impermeable layer causes flow around the auger hole to be primarily horizontal. Therefore, the GP method measures a predominantly horizontal field-saturated hydraulic conductivity in these thin soils. The measured conductivity represents a weighted average of the soil surrounding the submerged surface of the auger hole. In layered soil, the weight is greater for the layers close to the bottom of the hole than for those close to the top. Key words: Guelph permeameter, hydraulic conductivity, forest hydrology, permafrost, peat

scholarly journals Soil Improvement Using Waste Marble Dust for Sustainable Development

2021 ◽  
Vol 7 (9) ◽  
pp. 1594-1607
Author(s):  
Abdul Waheed ◽  
Muhammad Usman Arshid ◽  
Raja Abubakar Khalid ◽  
Syed Shujaa Safdar Gardezi
Keyword(s):  
Soil Improvement ◽  
Considerable Improvement ◽  
Collapsible Soil ◽  
Geotechnical Parameters ◽  
Suitable Material ◽  
Collapse Potential ◽  
Collapsible Soils ◽  
Marble Dust ◽  
Loss Of Strength ◽  
Very High

The soils which show very high shear strength in a dry state but rapidly lose their strength on wetting are known as collapsible soils. Such rapid and massive loss of strength produces severe distress leading to extensive cracking and differential settlements, instability of building foundations, and even collapse of structures built on these soils. Waste marble dust is an industrial byproduct and is being produced in large quantities globally poses an environmental hazard. Therefore, it is of the utmost need to look for some sustainable solution for its disposal. The present study focused on the mitigation of the collapse potential of CL-ML soil through a physio-chemical process. The soil is sensitive to wetting, warranting its stabilization. Waste marble dust (WMD) in varying percentages was used as an admixture. The study's optimization process showed that geotechnical parameters of collapsible soil improved substantially by adding waste marble dust. Plasticity was reduced while Unconfined Compressive Strength (UCS) significantly increased while swelling was reduced to an acceptable limit. The California Bearing Ratio (CBR) also exhibits considerable improvement. This study appraises the safe disposal of hazardous waste safely and turns these into suitable material for engineering purposes. Doi: 10.28991/cej-2021-03091746 Full Text: PDF

A COMPARISON OF THREE FIELD METHODS FOR MEASURING SATURATED HYDRAULIC CONDUCTIVITY

1985 ◽  
Vol 65 (3) ◽  
pp. 563-573 ◽  
Author(s):  
D. M. LEE ◽  
D. E. ELRICK ◽  
W. D. REYNOLDS ◽  
B. E. CLOTHIER
Keyword(s):  
Hydraulic Conductivity ◽  
Frequency Distribution ◽  
Sandy Loam ◽  
Measurement Techniques ◽  
Saturated Hydraulic Conductivity ◽  
Air Entrapment ◽  
Field Methods ◽  
Normal Frequency ◽  
Log Normal ◽  
Guelph Permeameter

The saturated hydraulic conductivity, Ks, was measured on a loamy sand, a fine sandy loam, a silt loam and a clay at four 100-m2-area sites in southern Ontario. Twenty measurements of Ks were obtained by each of three different measurement techniques at each of the four sites. The techniques included: (1) the air-entry permeameter method; (2) the constant head well permeameter method using the Guelph Permeameter; and (3) the falling-head permeameter method applied to small soil cores. The Ks data were found to be better described by the log-normal frequency distribution than by the normal frequency distribution. Statistical comparison of the mean Ks values [Formula: see text] indicated significant differences between some or all of the methods within each site. This site-method interaction was interpreted in terms of the influence of macropores and air entrapment on each of the measurement techniques. The measured Ks values ranged over an order of magnitude on the sand, one to two orders of magnitude on the loams, and three orders of magnitude on the clay. The [Formula: see text] estimates averaged over the three methods were: 3 × 10−5 m∙s−1 for the sand; 2 × 10−6 m∙s−1 for the loams and 1 × 10−7 m∙s−1 for the clay. Although all techniques were able to discriminate between the three soil types, the best choice of method for any particular situation appears dependent on the required type and accuracy of the Ks measurement, soil type, and the various practical constraints on the investigation. Key words: Air-entry permeameter, Guelph Permeameter, falling-head permeameter, spatial variability, macropores, entrapped air

scholarly journals Treatment of a collapsible soil using a bentonite–cement mixture

2018 ◽  
Vol 40 (4) ◽  
pp. 233-243 ◽  
Author(s):  
Soumia Bellil ◽  
Khelifa Abbeche ◽  
Ouassila Bahloul
Keyword(s):  
Arid Regions ◽  
Soil Aggregates ◽  
Spectroscopy Analysis ◽  
Collapsible Soil ◽  
Collapse Potential ◽  
Collapsible Soils ◽  
Before And After ◽  
Cement Mixture ◽  
Different Levels ◽  
Stable Material

Abstract The study of collapsible soils that are generally encountered in arid and semi-arid regions remains a major issue for geotechnical engineers. This experimental study, carried out on soils reconstituted in the laboratory, aims firstly to present a method of reducing the collapse potential to an acceptable level by treating them with different levels of bentonite–cement mixture while maintaining the water content and degree of compactness, thus reducing eventual risks for the structures implanted on these soils. Furthermore, a microscopic study using scanning electron microscopy was carried out to explore the microstructure of the soil in order to have an idea of the phenomena before and after treatment. The results show that treatment with a bentonite–cement mixture improves the geotechnical and mechanical characteristics, modifies the chemical composition of the soil, reduces the collapse potential and the consistency limits. The microstructural study and the X-ray energy dispersive spectroscopy analysis clearly illustrate an association of elementary particles in the soil aggregates, whereby the arrangement of these aggregates leads to the formation of a dense and stable material.

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