Measuring air-filled porosity changes in an irrigated swelling clay soil

Soil Research ◽  
1985 ◽  
Vol 23 (1) ◽  
pp. 15 ◽  
Author(s):  
NS Jayawardane ◽  
WS Meyer
Keyword(s):  
Moisture Content ◽  
Clay Soil ◽  
Soil Bulk Density ◽  
Swelling Clay ◽  
Volumetric Moisture Content ◽  
Neutron Count ◽  
Destructive Measurement ◽  
Non Destructive ◽  
Good Agreement

An in-situ method for measuring air filled porosity (�a) of soils using a neutron meter was developed and evaluated for a layered, swelling clay soil. Bulk density-volumetric moisture content relationships of soil layers were used to calculate the regressions of volumetric moisture content on �a. These regressions were combined with calibration equations of the neutron meter to obtain relationships between �a and neutron counts. The �a values predicted from measured neutron count ratios show good agreement with �a values calculated from the measured bulk densities and moisture contents in a transitional red-brown earth. The method provides a rapid and non-destructive measurement of �a. Soil aeration in a transitional red-brown earth under two irrigation treatments was assessed using neutron counts to monitor the changes in �a profiles. Large soil cores which were flooded had lower profile �a values than did cores which were not flooded. However, differences were small, owing apparently to the very low rates of infiltration and redistribution. The potential use of this method to continuously monitor changes in �a profiles allows frequent calculation of aeration stress indices, which may be used to predict crop responses and yield losses due to poor aeration.

In Situ Analysis of Hygrothermal Performance of the Sedlec Ossuary

2015 ◽  
Vol 1126 ◽  
pp. 22-27
Author(s):  
Zbyšek Pavlík ◽  
Lukáš Balík ◽  
Jiří Maděra ◽  
Lucie Kudrnáčová ◽  
Robert Černý
Keyword(s):  
Czech Republic ◽  
Moisture Content ◽  
Moisture Distribution ◽  
Wall Surface ◽  
Moisture Meter ◽  
Hygrothermal Performance ◽  
Historical Masonry ◽  
Destructive Measurement ◽  
Non Destructive

In situ analysis of hygrothermal state of the Sedlec Ossuary, Czech Republic, is presented in the paper. Within the experimental analysis, the measurement of moisture distribution in several profiles of historical masonry is done on a gravimetric principle. Non-destructive measurement of moisture content on the wall surface is done as well, using a capacitive moisture meter. Moreover, the interior and exterior climate is monitored over an almost two year period. On the basis of the obtained experimental results the hygrothermal conditions in both the masonry and the interior are assessed, including the identification of main moisture sources.

scholarly journals Characterization of Historic Binders and Stones of a Ruined Medieval Church (Hungary)

2020 ◽  
Author(s):  
Zsuzsanna Kósa ◽  
Ákos Török
Keyword(s):  
Moisture Content ◽  
Construction Materials ◽  
Selective Dissolution ◽  
Test Methods ◽  
Schmidt Hammer ◽  
Fine Grained ◽  
Medieval Church ◽  
History Of ◽  
Non Destructive

Construction materials of a partly ruined Medieval church of Central Hungary were studied in details to assess its conditions and to obtain information on the phases of construction. At first, digital images were taken to create a 3D model of the remaining walls. The material properties were measured in situ using non-destructive test methods. Strength parameters of stone and render were assessed by Schmidt hammer, while moisture content was measured by a portable moisture meter. According to lithological descriptions and thin-section analyses limestone prevail in the monument. The most common Miocene limestone is represented by various lithologies, such as cemented macro porous limestone, fine-grained porous limestone, oolitic limestone and bioclastic limestone. Mesozoic micritic well cemented limestone and Tertiary limonitic sandstone were also identified at the ruins. The most common weathering forms are selective dissolution, multiple flaking and biological colonisation. Renders used in the structure represents the long history of the structure from Medieval lime-based mortars to Portland cement containing latest applications. The former one is composed of quartz send in lime binder. According to Schmidt hammer tests, the rebound values of the replacement stone is higher than that of the original porous limestone. There is a distinct difference in the moisture content of the stone and render. Orientation/exposure of the wall also influences the moisture content. The gathered information allows for designing better repair methods and helps in the planning of the maintenance of the medieval stone heritage.

scholarly journals Methodology for the in situ testing of the moisture content of brick walls: an example of application

2020 ◽  
Vol 20 (4) ◽  
Author(s):  
Anna Hoła
Keyword(s):  
Moisture Content ◽  
Fourteenth Century ◽  
In Situ Testing ◽  
Negative Effects ◽  
Non Destructive ◽  
Historical Periods ◽  
Destructive Methods ◽  
Author Knowledge

Abstract The article presents original methodology of testing the moisture content of brick walls in buildings. It was developed on the basis of own experience acquired during testing the moisture content in many excessively wet buildings erected in various historical periods. The tests were conducted using different methods, including non-destructive methods. To emphasize the importance of the problem, an overview of the methodology was preceded by a brief presentation of the causes and negative effects of excessive moisture and salinity in brick walls. In addition, the article is illustrated with an example of the effects of moisture content tests carried out according to the developed methodology on a facility from the fourteenth century. According to the author, knowledge of the presented methodology, and its application, should contribute to both the improvement of the quality of conducted research and the credibility of the obtained results.

Field studies of water and salt movement in an irrigated swelling clay soil. III. Salt movement during ponding

Soil Research ◽  
1982 ◽  
Vol 20 (2) ◽  
pp. 101 ◽  
Author(s):  
DS McIntyre ◽  
J Loveday ◽  
CL Watson
Keyword(s):  
Clay Soil ◽  
Field Studies ◽  
In Situ Measurements ◽  
Swelling Clay ◽  
Before And After ◽  
Plough Layer ◽  
Water And Salt Movement

The effect of gypsum, incorporated into the plough layer of a saline, sodic, clay profile, on the leaching of salt, was determined from both in situ measurements, and from chloride determinations using samples taken before and after ponding. Observed differences in leaching patterns are attributed to water in the treated profile moving through interpedal macropores as well as through micropores within the peds (or matrix), but only through micropores in the untreated profile. The efficiency of the two mechanisms is discussed.

scholarly journals Indirect measurements of water content using TDR-inferred dielectric permittivity and electrical resistivity

2019 ◽  
Vol 92 ◽  
pp. 02005
Author(s):  
Bruna de Carvalho Faria Lima Lopes ◽  
Laís de Carvalho Faria Lima Lopes ◽  
Alessandro Tarantino
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Permittivity ◽  
Moisture Content ◽  
Water Content ◽  
Time Domain Reflectometry ◽  
Moisture Distribution ◽  
Salt Mines ◽  
Destructive Measurement ◽  
Non Destructive

The measurement of moisture distribution in Engineered Barrier Systems (EBS) in salt mines and deep geological disposals is essential in order to monitor fluid ingress and record data for long-term security analyses. Additionally, soil moisture content has influence over the mechanical properties of the soil as well as plant growth, soil stability and contaminant transport to cite some. Therefore, finding affordable and reliable ways to determine moisture content, quickly and in the field without sampling, is of great interested among people in different subject areas. Time-domain reflectometry (TDR) has become a recognized electromagnetic method for non-destructive measurement of dielectric permittivity and electrical conductivity of moist porous materials. It turns out that both these measurements depend on the material moisture content, among other things. This paper presents a series of calibration tests performed on soil samples. TDR probes were used to obtain the dielectric permittivity and electrical conductivity of the samples. As a consequence, relationships between these measurements and the samples' volumetric water content were later established. These relationships can then be used to indirectly determine that important information of water content on similar soil material using cheap, quick and non-destructive TDR probes.

scholarly journals Experimental Study on the Effect of Water on the Properties of Cast In Situ Foamed Concrete

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Wenhui Zhao ◽  
Qian Su ◽  
Wubin Wang ◽  
Lele Niu ◽  
Ting Liu
Keyword(s):  
Compressive Strength ◽  
Elastic Modulus ◽  
Moisture Content ◽  
Water Level ◽  
Immersion Time ◽  
Drying Shrinkage ◽  
Dry Density ◽  
Volumetric Moisture Content ◽  
Foamed Concrete

This study aims to investigate the effect of water on the properties of cast in situ foamed concrete with a dry density of 300–800 kg/m3 (100 kg/m3 is a gradient). Firstly, the shrinkage deformation with the curing time and the volumetric moisture content is studied by the drying shrinkage test and improved drying shrinkage test. Secondly, the influence of volumetric moisture content on mechanical properties is assessed. At last, the effects of immersion time and immersion type on the mechanical properties of foamed concrete are studied by considering the water-level conditions. The achieved results show that the shrinkage deformations increase with the curing time for the drying shrinkage test and the improved drying shrinkage test, while the variations are different. The shrinkage deformation increases with the decrease of volumetric moisture content for six dry densities of foamed concrete. Besides, it gradually changes in the early stage, while it changes fast in the later stage. The compressive strength and elastic modulus decrease with the increase of volumetric moisture content for each density. For the water-level unchanged condition, the compressive strength and elastic modulus initially decrease and then slowly increase with the increase of the immersion time. For the water-level changed condition, the compressive strength and elastic modulus of foamed concrete decrease with the increase of immersion time for each dry density, and the rate of early attenuation is high, whereas the rate of later attenuation is limited.

scholarly journals Calibration of Acoustic Emission Parameters in Relation to the Equilibrium Moisture Content Variations in a Pinus sylvestris Beam

2021 ◽  
Vol 11 (11) ◽  
pp. 5236
Author(s):  
Beatrice Bartolucci ◽  
Francesca Frasca ◽  
Anna Maria Siani ◽  
Chiara Bertolin
Keyword(s):  
Acoustic Emission ◽  
Moisture Content ◽  
Pinus Sylvestris ◽  
Equilibrium Moisture Content ◽  
Testing Machine ◽  
Acoustic Emissions ◽  
Image Correlation ◽  
Experimental Procedure ◽  
Non Destructive

Under constant temperature conditions, air relative humidity variations affect hygroscopic objects, such as wood, modifying their moisture content and provoking, at low values, damages and fractures. The parameters (amplitude, counts, and energy) derived from the acoustic emission non-destructive technique are calibrated with respect to equilibrium moisture content values using 14 samplings of Pinus sylvestris. The experimental procedure uses multi-technique approaches involving a universal testing machine, digital image correlation, and acoustic emissions, and notes that the three parameters of acoustic emission strictly depend on the equilibrium moisture content. For a better interpretation, a statistical approach is applied to model the equilibrium moisture content variations radially and longitudinally. Amplitude, counts, and energy are calibrated as a function of the equilibrium moisture content, indicating that all three parameters are necessary to have an integral vision of the conservation of a wooden material. Moreover, the shape of the macro-fractures that occur at the surface can be associated with the level of moisture or dryness of the sample. Finally, the proposed method can be used in situ because, through acoustic emission monitoring, it is possible to quantify the fingerprint of the state of conservation of a material.

Sign in / Sign up

Export Citation Format

Share Document