scholarly journals Valuation of the capillary uptake phenomenon in the wall of the historic building using the surface TDR probe

2013 ◽  
Vol 12 (4) ◽  
pp. 083-093
Author(s):  
Zbigniew Suchorab ◽  
Stanisław Fic ◽  
Danuta Barnat-Hunek
Keyword(s):  
Building Materials ◽  
Quantitative Estimation ◽  
Capillary Rise ◽  
Visual Observation ◽  
Time Domain Reflectometry ◽  
Capillary Uptake ◽  
Historical Objects ◽  
Vertical Variations ◽  
Uptake Process ◽  
Moisture Detection

Article discusses measuring potential of the TDR (Time Domain Reflectometry) technique for terrain measurement of moisture in the masonries of the historical buildings. For the measurements it was applied modified TDR probe which enables noninvasive moisture detection in building materials, thus enables its application for in-situ measurements, especially in old, historical objects. Terrain measurements were realized on the external masonry made of red ceramic brick, being the part of the historical hospital located on the area of the “Wojewódzki Samodzielny Psychiatryczny Zespół Publicznych Zakładów Opieki Zdrowotnej im. prof. dr Jana Mazurkiewicza” in Pruszków. The masonry is stricken with capillary rise phenomenon by the water coming from the ground, which is also visible by visual observation. Conducted measurement enabled quantitative estimation of the phenomenon which threatens to the discussed object. Within the research, reflectometric measurements were conducted using the prototype surface TDR probes. Measurements were repeated to verify moisture changes in time. First series of measurement was conducted in summertime, in July 2010. The second one was conducted in November of the same year. Then, with the obtained data there were drawn moisture maps of the masonry, which indicated horizontal and vertical variations of moisture and interpretation of the obtained results enabled to confirm capillary uptake process in the examined masonry.

scholarly journals A Noninvasive TDR Sensor to Measure the Moisture Content of Rigid Porous Materials

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3935 ◽  
Author(s):  
Zbigniew Suchorab ◽  
Marcin Widomski ◽  
Grzegorz Łagód ◽  
Danuta Barnat-Hunek ◽  
Dariusz Majerek
Keyword(s):  
Moisture Content ◽  
Porous Materials ◽  
Building Materials ◽  
Capillary Rise ◽  
Capacitive Sensor ◽  
Time Domain Reflectometry ◽  
Capillary Uptake ◽  
Individual Calibration ◽  
Sample Application ◽  
The Time Domain

The article presents the potential application of the time domain reflectometry (TDR) technique to measure moisture transport in unsaturated porous materials. The research of the capillary uptake phenomenon in a sample of autoclaved aerated concrete (AAC) was conducted using a TDR sensor with the modified construction for non-invasive testing. In the paper the basic principles of the TDR method as a technique applied in metrology, and its potential for measurement of moisture in porous materials, including soils and porous building materials are presented. The second part of the article presents the experiment of capillary rise process in the AAC sample. Application of the custom sensor required its individual calibration, thus a unique model of regression between the readouts of apparent permittivity of the tested material and its moisture was developed. During the experiment moisture content was monitored in the sample exposed to water influence. Monitoring was conducted using the modified TDR sensor. The process was additionally measured using the standard frequency domain (FD) capacitive sensor in order to compare the readouts with traditional techniques of moisture detection. The uncertainty for testing AAC moisture, was expressed as RMSE (0.013 cm3/cm3) and expanded uncertainty (0.01–0.02 cm3/cm3 depending on moisture) was established along with calibration of the applied sensor. The obtained values are comparable to, or even better than, the features of the traditional invasive sensors utilizing universal calibration models. Both, the TDR and capacitive (FD) sensor enabled monitoring of capillary uptake phenomenon progress. It was noticed that at the end of the experiment the TDR readouts were 4.4% underestimated and the FD readouts were overestimated for 12.6% comparing to the reference gravimetric evaluation.

scholarly journals Capillary Uptake Monitoring in Lime-Hemp-Perlite Composite Using the Time Domain Reflectometry Sensing Technique for Moisture Detection in Building Composites

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1677 ◽  
Author(s):  
Przemysław Brzyski ◽  
Zbigniew Suchorab
Keyword(s):  
Thermal Conductivity ◽  
Apparent Density ◽  
Time Domain ◽  
Building Materials ◽  
Gravimetric Method ◽  
Total Porosity ◽  
Time Domain Reflectometry ◽  
Partial Replacement ◽  
Wall Material ◽  
Capillary Uptake

The use of waste plants in the production of building materials is consistent with the principles of sustainable development. One of the ideas involves using hemp shives as an aggregate for the production of a composite used as a filling of the timber frame construction of the walls. The most important disadvantage of using the building materials based on organic components is their susceptibility to the water influence. The wall material is exposed to rising groundwater. The research part of the paper presented the preparation method and the investigation of the hemp-perlite-lime composites. Flexural and compressive strength, apparent density, total porosity, thermal conductivity, and mass absorptivity were examined. The main research part pertained to the analysis of capillary uptake occurrence in the composites, being the important phenomenon present in the external walls. The study on this phenomenon was carried out using the technique of indirect moisture evaluation—Time Domain Reflectometry (TDR). The indirect readouts were additionally verified with the traditional evaluation using the gravimetric method based on the PN-EN 1925 standard. The study proved that the tested composites were characterized by low apparent density, thermal conductivity, strength parameters, high total porosity, and mass absorptivity. The partial replacement of hemp shives by expanded perlite had a beneficial effect on the tested properties of composites.

scholarly journals Methodology of Moisture Measurement in Porous Materials Using Time Domain Reflectometry / Metodyka Prowadzenia Badań Wilgotności W Ośrodkach Porowatych Za Pomocą Reflektometrii W Domenie Czasu

2014 ◽  
Vol 19 (1-2) ◽  
pp. 97-107 ◽  
Author(s):  
Zbigniew Suchorab ◽  
Marcin K. Widomski ◽  
Grzegorz Łagód ◽  
Danuta Barnat-Hunek ◽  
Piotr Smarzewski
Keyword(s):  
Porous Materials ◽  
Time Domain ◽  
Building Materials ◽  
Capillary Rise ◽  
Time Domain Reflectometry ◽  
Gravimetric Measurement ◽  
Basic Principles ◽  
Measuring Setup ◽  
Measurement Methodology ◽  
Aerated Concrete

Abstract The article presents the description of measurement methodology of moisture transport in unsaturated porous materials using Time Domain Reflectometry (TDR) technique on the example of measurement of capillary uptake phenomenon in the sample of autoclaved aerated concrete (AAC). In the paper there are presented basic principles of the TDR method as a technique applied in metrology, its potential for measurement of moisture in porous materials like soils and porous building materials. Second part of the article presents the experiment of capillary rise process in the sample of AAC. Within the experiment moisture content was monitored in the sample exposed on water influence. Monitoring was conducted using TDR FP/mts probes. Preparation of the measuring setup was presented in detail. The TDR readouts post-processing, graphical presentations of the obtained results, short discussion and comparison of TDR readouts to gravimetric measurement were also presented.

scholarly journals Moisture measurements of the chalk rock walls from Kazimierz Dolny with the application of TDR method

2008 ◽  
Vol 2 (1) ◽  
pp. 125-140
Author(s):  
Zbigniew Suchorab ◽  
Danuta Barnat-Hunek ◽  
Henryk Sobczuk
Keyword(s):  
Time Domain ◽  
Building Materials ◽  
Capillary Rise ◽  
Good Alternative ◽  
Time Domain Reflectometry ◽  
Composition Analysis ◽  
Physical Parameters ◽  
Water Parameters ◽  
Vistula River ◽  
Structure Changes

The article presents monitoring measurements of the physical parameters and mineralogical-petrographical composition analysis of the chalk rock from the Kazimierz Dolny region. The experiments involve the reflectometric techniques TDR (Time Domain Reflectometry) as a perspective alternative in moisture determinations. The investigation domain was the stone from the Castle of Janowiec by the Vistula river, which walls indicate the progressive corrosion depending on external exposition and age. Other object of investigations was the stone from quarry in Kazimierz Dolny. Porosimetric examinations of the chalk rock from the southern and northern elevation of the castle indicate differences in structure changes of the stones. These differences influence different behaviour of the chalk rock during capillary rise of water and salt solutions. It is connected with the suitable matching of the conservation protection, wall protecting preparations which kind and application depend on porosimetric parameters of the material. The TDR method is applied as a good alternative of water transport measurement in porous building materials and other water parameters characterisig described material.

scholarly journals Free of Volatile Organic Compounds Protection against Moisture in Building Materials/Zabezpieczenia Przegród Budowlanych Przed Wilgocią Wolne Od Lotnych Związków Organicznych

2014 ◽  
Vol 21 (3) ◽  
pp. 401-411 ◽  
Author(s):  
Zbigniew Suchorab ◽  
Danuta Barnat-Hunek ◽  
Piotr Smarzewski ◽  
Zbyšek Pavlík ◽  
Robert Černý
Keyword(s):  
Water Uptake ◽  
Building Materials ◽  
Surface Condition ◽  
Time Domain Reflectometry ◽  
Physical Parameters ◽  
Non Invasive ◽  
Uptake Process ◽  
Moisture Protection ◽  
The Time Domain ◽  
Moisture Estimation

Abstract The article presents information about moisture protection of building materials. The discussed parameters determining the efficiency of the water protection are material porosity, water absorptivity and surface condition of building materials. Moreover the ecological aspect of hydrophobic VOC-free preparations available on the market has been underlined. The first part of the article is a description of moisture problem in the building envelopes and the possibilities of its prevention. The special attention is put on the electric methods of moisture estimation with a special emphasis on the Time Domain Reflectometry (TDR) method. The second part of the article is devoted an experiment of model red-brick walls exhibited on capillary uptake process. For the experiment three model red-brick walls were built and prepared for water uptake process. The experiment was monitored by the capacitive and surface TDR probes thanks to which the necessity of sampling and material destruction could be avoided. Conducted experiments show the progress of water uptake phenomenon in the model walls which differ in type of protection against moisture and prove the potential of the non-invasive measurements using the surface TDR probes. Basic physical parameters of the applied bricks were determined together with the reflectometric measurements. Furthermore, Scanning Electron Microscopy (SEM) was used to analyze the hydrophobic layer continuity.

scholarly journals Time Domain Reflectometry (TDR) technique – A solution to monitor moisture content in construction materials

2020 ◽  
Vol 172 ◽  
pp. 17001
Author(s):  
Teresa Stingl Freitas ◽  
Ana Sofia Guimarães ◽  
Staf Roels ◽  
Vasco Peixoto de Freitas ◽  
Andrea Cataldo
Keyword(s):  
Moisture Content ◽  
Time Domain ◽  
Building Materials ◽  
Correct Diagnosis ◽  
Construction Materials ◽  
Gravimetric Method ◽  
Reference Method ◽  
Time Domain Reflectometry ◽  
Relative Dielectric Permittivity ◽  
Porous Building Materials

Measuring moisture content in building materials is crucial for the correct diagnosis of buildings’ pathologies and for the efficiency evaluation of the treatment solution applied. There are several different techniques available to measure the moisture content in construction materials. However, perform long-term minor-destructive measurements is still a great challenge. The TDR – Time Domain Reflectometry – technique is commonly used for moisture content measurements in soils, but is considered a relatively new method with regard to its application in construction materials. In the present state of research, the current use of the TDR technique for monitoring moisture content in all types of consolidated porous building materials is not possible yet. Indeed, the empirical conversion functions proposed for soils are mostly not suitable for building materials. Furthermore, to successfully use the TDR technique, a good contact between the TDR probe and the material under study is required, which may be difficult to achieve in hard materials. In this paper, the TDR technique was implemented in two limestone walls constructed in the lab to test experimentally the efficiency of a wall-base ventilation channel to speed up drying after a flood. Each wall was equipped with four two-rod TDR probes for continuous monitoring the moisture content in both situations: with and without the ventilation channel. All the equipment used, procedures followed during the drilling until the probes’ final installation, as well as the individual calibration required for each probe are explained in detail. Instead of using unsuitable functions proposed for soils, the evaluation of the moisture content from the apparent relative dielectric permittivity measured was established using as reference method the gravimetric method. The results obtained suggest that the TDR technique is suitable for moisture content monitoring in consolidated porous building materials.

Sampling, Analysis, and Risk Assessment for Asbestos and Other Mineral Fibers in Soil

2020 ◽  
Vol 26 (1) ◽  
pp. 121-127
Author(s):  
Ed Cahill
Keyword(s):  
Electron Microscopy ◽  
Building Materials ◽  
Sampling Site ◽  
Polarized Light ◽  
Analytical Techniques ◽  
Visual Observation ◽  
Natural Occurrence ◽  
Cost Constraints ◽  
Assessment Time ◽  
Analytical Result

ABSTRACT Asbestos may be present in soil as a natural occurrence or by contamination from asbestos-containing building materials, illegal dumping of asbestos, or other human activities. When trying to properly assess asbestos and other mineral fiber content in a sample by microscopy, soil is a problem matrix in all respects. Even defining the sample to be collected requires forethought and can greatly influence the final analytical result. Determining the sampling approach as well as the best sample preparation and analysis techniques are critical to obtaining accurate results in a metric that is useful to the end user. This article provides an overview of the various approaches that can be applied to assist those involved with asbestos in soil projects. There are many analytical techniques that can be applied for the determination of asbestos content in soil, including visual observation in the field, stereomicroscopy, polarized light microscopy, scanning electron microscopy, transmission electron microscopy, x-ray diffraction, and others. All of these techniques have their own inherent strengths and weaknesses. Fortunately all of the analysis options are complementary, and using multiple techniques can help to better characterize a sampling site and provide a more comprehensive assessment. Time and cost constraints will typically play a role in determining the final sampling and analysis plan.

Quantitative, zerstörungsfreie Feuchtemessung in Baustoffen vor Ort mit der Time Domain Reflectometry / Quantitative, non-destructive moisture measurement in building materials on site by time-domain re ectometry

1999 ◽  
Vol 5 (6) ◽  
pp. 609-618
Author(s):  
M. Stacheder ◽  
G. Grassegger ◽  
F. Grüner
Keyword(s):  
Time Domain ◽  
Building Materials ◽  
Salt Content ◽  
Time Domain Reflectometry ◽  
New Method ◽  
Measuring Methods ◽  
Surface Moisture ◽  
Non Destructive ◽  
Floor Cover

Abstract A new commercially available dielectric technique for the non-destructive determination of moisture in building materials based on the principle of 'time-domain reflectometry' (TDR) is presented. TDR measurements on samples of sandstone, brick, concrete and floor cover matched very well with results of conventional moisture measuring methods such as oven-drying or calciumcarbide-technique. The new method showed only a low influence of salt content or surface moisture of the material on the results.

scholarly journals Investigation of cytotoxic activity and dissolution improvement of Teniposide by incorporation into acid treated carbon nanotube and dispersed by hydrophilic polymer

2019 ◽  
Vol 28 (1) ◽  
pp. 91-100
Author(s):  
Raid Mohamed Al abood ◽  
Mowafaq M. Ghareeb ◽  
Alaa A. Abdulrasool
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Cytotoxic Activity ◽  
Quantitative Estimation ◽  
Visual Observation ◽  
Pharmaceutical Properties ◽  
Treated Carbon ◽  
Functionalization Of Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Strong Acids

Single Walled Carbon nanotubes (SWCNTs), as nano-needle structures, are good candidates as nanocarrier delivery systems that carry drug to the site of action. They are good due to their unique pharmaceutical properties. Teniposide is an anticancer drug, which is widely used, but it has a problem of low solubility. In this study, to improve the properties of carbon nanotubes, pre-functionalization of carbon nanotubes via carboxylation with strong acids has been performed and then functionalized through attaching them to the polymer and copolymer. Concurrently, a proper polymer-copolymer combination has been selected by the UV-Visible spectrometer at 880nm. It is selected based on the qualitative dispersibility analysis, the visual observation of homogeneity, and separation tendency after centrifugation while quantitative estimation. The best formula is further studied utilizing FTIR, SEM, TEM, the solubility of Teniposide, and cytotoxicity through cell lines analysis.             The results show that the best dispersibility obtained in the formula that used PVA as polymer and PEO as copolymer at a ratio of 1:1. The solubility of incorporated Teniposide in the selected formula is increased by 11.5 fold and the cell line study shows significant improvement in cytotoxic activity of Teniposide. Accordingly, it can be concluded that the acid treated carbon nanotube and linked by polymer improve the pharmaceutical properties of the carrier and actively increase the potency of drug.

Sign in / Sign up

Export Citation Format

Share Document