Granular soils in rigid-wall permeameters: method for determining the degree of saturation

1989 ◽  
Vol 26 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Robert P. Chapuis ◽  
Karsten Baass ◽  
Luc Davenne
Keyword(s):  
Hydraulic Conductivity ◽  
Test Procedure ◽  
Rigid Wall ◽  
Standard Test ◽  
Test Method ◽  
Degree Of Saturation ◽  
Granular Soils ◽  
Test Results ◽  
Constant Head

The standard test method used to determine the hydraulic conductivity of a clean granular soil (rigid-wall permeameter –constant head difference) requires that the specimen be saturated with an air-vacuum pump. However, no method is provided to verify whether the sample is fully (100%) saturated. This paper proposes such a method and establishes its accuracy. The method allows for quality control of the rigid-wall permeameter itself: it can detect if it is watertight but not airtight, according to the achieved degree of saturation. A detailed example is given on a proposed data sheet. The reasons for partial saturation and the problems related to air bubbles are examined. The result of this examination is a simplified test to check a permeameter, based on the fact that for unsaturated conditions the hydraulic conductivity depends on which of two ways the water seeps in a given direction. A few modifications in the preparation of the specimen and the test procedure are suggested so as to improve the quality of test results. Key words: permeability, laboratory, granular soils, rigid-wall permeameter, saturation.

Towards a more rational approach to chemical compatibility testing of clay

2002 ◽  
Vol 39 (3) ◽  
pp. 597-607 ◽  
Author(s):  
J K Kodikara ◽  
F Rahman ◽  
S L Barbour
Keyword(s):  
Boundary Condition ◽  
Hydraulic Conductivity ◽  
Rigid Wall ◽  
New Technique ◽  
Rational Approach ◽  
Lateral Strain ◽  
Test Results ◽  
Chemical Compatibility ◽  
Test Technique ◽  
Flexible Wall

Chemical compatibility tests using hydraulic conductivity testing with chemical permeants are normally undertaken to assess the integrity of compacted clayey liners used for waste containment. This paper highlights the fact that current routine methods of flexible wall and rigid wall testing techniques fail to represent the zero lateral strain boundary condition that is required to realistically represent the field situation. The test results indicate that flexible wall permeameters underestimate the likely increases in hydraulic conductivity due to chemicals, while the rigid wall permeameters can severely overestimate these effects. A new test technique, which incorporates the zero lateral strain condition in a simple manner, is presented. This technique involves the use of a rigid wall concept in a flexible wall permeameter. A split rigid mould is used to encase the soil specimen that is glued to the internal surfaces of the mould, to apply the zero lateral strain boundary condition. The new technique is shown to be suitable for both chemical compatibility and desiccation testing. The tests were undertaken with varying concentrations of saline water, methanol, and landfill leachate. The test results indicate that the new technique produces results that fall between the results obtained from flexible wall and rigid wall permeameters. It is argued that the new test technique provides a more rational approach for chemical compatibility testing than the current rigid wall and flexible wall techniques.Key words: soil, hydraulic conductivity, chemical compatibility, landfill, permeameter, boundary condition.

scholarly journals An approach to identify soil types by using hydraulic conductivity values

2018 ◽  
Vol 2 (1) ◽  
pp. 43-51
Author(s):  
Maritha Nilam Kusuma ◽  
Wahyono Hadi ◽  
Budisantoso Wirjodirdjo ◽  
Yulfiah Yulfiah
Keyword(s):  
Water Treatment ◽  
Hydraulic Conductivity ◽  
Preliminary Analysis ◽  
Soil Types ◽  
Main Role ◽  
Important Indicator ◽  
Pre Treatment ◽  
Constant Head ◽  
Soil Filtration

Water treatment in Indonesia still uses coagulant to reduce the contaminant. Therefore, an infiltration gallery is required as the pre-treatment before conventional water treatment conducted. Infiltration gallery is a natural technology for absorbing or filtrating the contaminant. The hydraulic conductivity plays the main role in soil filtration. There are many types of soil with different hydraulic conductivities. In infiltration gallery method it is important to identify the hydraulic conductivity value as the preliminary analysis because it is the important indicator to show the ability of soil to flow the water from one side to other sides when filtrating the contaminant. The slower the conductivity is, the better the quality of the water will be. The method used in this study was the Constant head Permeameter. The result of this study shows that the same type of soil type has different hydraulic conductivities.

A constant-head pumping test method using direct-push equipment for in situ hydraulic conductivity measurements

Géotechnique ◽  
2012 ◽  
Vol 62 (3) ◽  
pp. 253-262 ◽  
Author(s):  
T. KOBAYASHI ◽  
H. ONOUE ◽  
S. OBA ◽  
N. YASUFUKU ◽  
K. OMINE
Keyword(s):  
Hydraulic Conductivity ◽  
Pumping Test ◽  
Test Method ◽  
Conductivity Measurements ◽  
Direct Push ◽  
Constant Head

Parameters on Fracture Strength of Sea Ice

1983 ◽  
Vol 105 (1) ◽  
pp. 12-16 ◽  
Author(s):  
N. Urabe ◽  
A. Yoshitake ◽  
T. Iwasaki ◽  
M. Kawahara
Keyword(s):  
Fracture Toughness ◽  
Sea Ice ◽  
Strain Rate ◽  
Fracture Strength ◽  
Test Procedure ◽  
Standard Test ◽  
Test Method ◽  
Beam Specimen ◽  
Crushing Strength ◽  
Brackish Ice

Compressive crushing strength on brackish ice and sea ice and fracture toughness value on sea ice were measured as parameters associated with fracture strength of ice. The compressive crushing strength depends on salinity, temperature and strain rate. At constant salinity and temperature, the strength increased with increase in strain rate and reached maximum value at about a strain rate of 10−3 s−1, then decreased with increase in strain rate. An empirical equation to estimate the compressive crushing strength was derived as a function of brine volume, temperature and strain rate. As far as fracture toughness is concerned, a simplified test procedure on notched cantilever beam specimen was developed in order to avoid complicated manipulation in field conditions. The fracture toughness value (KIC) coincided well with the value obtained from fracture toughness tests conducted in conformity with the standard test method.

scholarly journals Comparison of European Standard Patch Test Results of 330 Patients from an Occupational Diseases Hospital

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Özge Gündüz ◽  
Aslı Aytekin ◽  
Engin Tutkun ◽  
Hınç Yılmaz
Keyword(s):  
Patch Test ◽  
Preventive Measures ◽  
Potassium Dichromate ◽  
Standard Test ◽  
Working Environment ◽  
Test Results ◽  
European Standard ◽  
Household Activities

Background and Aim.Contact dermatitis (CD) is the most prevalent occupational skin disease with a significant impact on quality of life. Patch testing is used for the identification of responsible allergens which may improve protective and preventive measures in the workplace. Herein, we aim to identify the demographic characteristics and occupation of patients with early diagnosis of occupational CD and compare patch test results.Materials and Methods.The study included 330 patients referred to our clinic between April 2009 and April 2011 and who were patch-tested with 28-allergen European Standard Test.Results.126 (38%) patients were female and 204 (62%) were male with a mean age of 36.12 (±13.13) years. Positive allergic reactions were observed in 182 (55%) patients. Nickel sulphate (41/126) and potassium dichromate (39/204) were significantly the most common allergens in women and men, respectively (P<0.005). Additionally, the most common occupation in women was household activities (83/126) and in men was manufacturing (80/204).Conclusion.The allergens to which people become sensitized differ according to their working environment and occupation. Classification of occupations is important for identification of sensitization risks and monitoring of changes in allergen distribution of different occupations.

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