Influence of Moisture and Temperature of Calcium Silicate Bricks on Results of Measurements with Rebound Hammer

2014 ◽  
Vol 1000 ◽  
pp. 352-355
Author(s):  
Jiří Brožovský
Keyword(s):  
Moisture Content ◽  
Calcium Silicate ◽  
Fine Aggregate ◽  
Hydration Products ◽  
Technical Literature ◽  
Rebound Hammer ◽  
Fine Grained ◽  
Surface Moisture ◽  
Measurement Results ◽  
Material Temperature

Testing with rebound hammers is influenced by various factors, like composition and components of tested material, treatment of tested surface, moisture content of tested material, temperature of material and environment. Influence of these factors on measurement results during testing concrete is described in technical literature and standards. Calcium silicate body can be characterized as non-cement based fine grained concrete, however, with considerably higher water absorbing capacity compared to standard concrete: ca 12-14% (fine aggregate bonded by hydration products of lime). To use rebound hammers for testing calcium silicate bricks, influence of selected factors on measurement results was tested. It was proved, that content of moisture and temperature of calcium silicate brick has influence on results of measurements with rebound hammer, and therefore it is necessary to take into account these influences.

Temporal and spatial variabilities in the surface moisture content of a fine-grained beach

Geomorphology ◽  
2010 ◽  
Vol 114 (3) ◽  
pp. 303-310 ◽  
Author(s):  
S.L. Namikas ◽  
B.L. Edwards ◽  
M.C.A. Bitton ◽  
J.L. Booth ◽  
Y. Zhu
Keyword(s):  
Moisture Content ◽  
Fine Grained ◽  
Surface Moisture ◽  
Temporal And Spatial

scholarly journals Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff
Keyword(s):  
Large Scale ◽  
Measurement Data ◽  
Fine Grained ◽  
Dredged Materials ◽  
Measurement Results ◽  
Large Scale Field ◽  
Eigenvalue Ratio ◽  
Ill Posed ◽  
Materials Used ◽  
Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

scholarly journals Influence of moisture content on the contact angle and surface tension measured on birch wood surfaces

2021 ◽  
Author(s):  
Rami Benkreif ◽  
Fatima Zohra Brahmia ◽  
Csilla Csiha
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Moisture Content ◽  
Solid Wood ◽  
Contact Angles ◽  
Surface Moisture ◽  
Wood Coatings ◽  
The Relationship ◽  
Wood Surfaces

AbstractSurface tension of solid wood surfaces affects the wettability and thus the adhesion of various adhesives and wood coatings. By measuring the contact angle of the wood, the surface tension can be calculated based on the Young-Dupré equation. Several publications have reported on contact angle measured with different test liquids, under different conditions. Results can only be compared if the test conditions are similar. While the roles of the drop volume, image shooting time etc., are widely recognized, the role of the wood surface moisture content (MC) is not evaluated in detail. In this study, the effect of wood moisture content on contact angle values, measured with distilled water and diiodomethane, on sanded birch (Betula pendula) surfaces was investigated, in order to find the relationship between them. With increasing MC from approximately 6% to 30%, increasing contact angle (decreasing surface tension) values were measured according to a logarithmic function. The function makes possible the calculation of contact angles that correspond to different MCs.

scholarly journals AN EFFECTIVE WAY TO RECYCLE 3D PRINTING CONCRETE SCRAP

2021 ◽  
Vol 4 (2) ◽  
pp. 12-18
Author(s):  
D.A. Tolypin ◽  
N. Tolypina
Keyword(s):  
Compressive Strength ◽  
3D Printing ◽  
Portland Cement ◽  
Quartz Sand ◽  
Raw Materials ◽  
Electricity Consumption ◽  
Cement Matrix ◽  
Fine Aggregate ◽  
Fine Grained ◽  
Control Samples

the article proposes a rational method for processing 3D printing concrete scrap using vibration equipment, which allows obtaining a multicomponent building material with minimal electricity consumption. As a crite-rion for the degree of grinding of concrete scrap, it is proposed to use the specific surface area of the finely dispersed part of concrete scrap, which should correspond to 400-500 m2/kg. The possibility of reusing the resulting product instead of the traditional fine aggregate of quartz sand is shown. It was found that the con-crete scrap without the addition of Portland cement hardens, reaching up to 48% of the compressive strength of the control samples by 28 days. When 10% of the binder CEM I 42.5 N was added to the concrete scrap processing product, the compressive strength of fine-grained concrete increased by 106.6%, and 20% of Portland cement - by 112.2 %, compared to the strength of control samples of a similar composition on tra-ditional quartz sand after 28 days of hardening. It is noted that this is primarily due to the weak contact zone of quartz sand and the cement matrix of concrete. The use of the product of processing concrete scrap al-lows obtaining building composites based on it with the complete exclusion of natural raw materials

scholarly journals Sources and Uses of Fuel for Fish Smoking Around the Lake Chad in Borno State, Nigeria

2015 ◽  
Vol 6 (2) ◽  
pp. 78 ◽  
Author(s):  
Yerima I. ◽  
Y. M. Ngulde
Keyword(s):  
Moisture Content ◽  
Analysis Of Variance ◽  
Large Volume ◽  
Coefficient Of Variation ◽  
Rice Hull ◽  
Fishing Community ◽  
Acacia Senegal ◽  
Lake Chad ◽  
Energy Value ◽  
Surface Moisture

<p>Fuel around the rural fishing community of the Lake Chad in Borno state is scarce and expensive. Where it is available it is at a distance of 120km therefore alternative and strategy must be developed to provide fuel to the fishing community to preserve the large volume of fish landed around the Lake Chad. A visit was made to the lake shores to identify the various types of materials in use by the processors as fuel and analysis of the fuel types were made, especially moisture content being the most important factor in determining the energy value of a fuel.  The fuel types were compared to the type and quantity of fish landed daily. The analysis of variance between paired fuel types was found to be significant at 1% with low coefficient of variation. In this study Eucalyptus camaldulenis and Acacia senegal were found to have the least moisture content and available to processors. Rice hull which has a 0.001% surface moisture content was not known to the processors as biofuel. Which we hope to introduced at the end of the research. The use of cowdung was always minimized due to its social ills. </p>

scholarly journals Predicting rut depth induced by an 8-wheeled forwarder in fine-grained boreal forest soils

2020 ◽  
Vol 77 (2) ◽  
Author(s):  
Jori Uusitalo ◽  
Jari Ala-Ilomäki ◽  
Harri Lindeman ◽  
Jenny Toivio ◽  
Matti Siren
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Bulk Density ◽  
Soil Moisture Content ◽  
Mineral Soil ◽  
Coarse Grained ◽  
Forest Operations ◽  
Fine Grained ◽  
Humus Layer ◽  
Cumulative Mass

Abstract Key message Rut depth in fine-grained boreal soils induced by an 8-wheeled forwarder is best predicted with soil moisture content, cumulative mass of machine passes, bulk density and thickness of the humus layer. Context Forest machines are today very heavy and will cause serious damage to soil and prevent future growth if forest operations are carried out at the wrong time of the year. Forest operations performed during the wettest season should therefore be directed at coarse-grained soils that are not as prone to soil damage. Aims The study aimed at investigating the significance of the most important soil characteristics on rutting and developing models that can be utilized in predicting rutting prior to forest operations. Methods A set of wheeling tests on two fine-grained mineral soil stands in Southern Finland were performed. The wheeling experiments were conducted in three different periods of autumn in order to get the largest possible variation in moisture content. The test drives were carried out with an 8-wheeled forwarder. Results Soil moisture content is the most important factor affecting rut depth. Rut depth of an 8-wheeled forwarder in fine-grained boreal soil is best predicted with soil moisture content, cumulative mass of machine passes, bulk density and thickness of the humus layer. Conclusion The results emphasize the importance of moisture content on the risk of rutting in fine-grained mineral soils, especially with high moisture content values when soil saturation reaches 80%. The results indicate that it is of high importance that soil type and soil wetness can be predicted prior to forest operations.

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