Abrasion Resistance Values Research Articles

Effect of the filler content on some physical and mechanical properties of virgin- and recycled thermoplastic polyurethane composites

Effects of thermoplastic polyurethane (TPU) types (Recycled (R) and Virgin (V)) composites with 15 wt% and 30 wt% oakwood flour addition were studied. Selected physical, mechanical, morphological, and thermal properties of resulting polymer composites were analyzed. Test samples were manufactured using injection molding, except that abrasion resistance specimens were manufactured using a compression molding process. The findings indicated that the types of TPU and filler contents played a significant role in the density and mechanical properties of the TPU test samples. The increased oak wood flour contents in both TPU types showed improvement in density, tensile modulus, hardness, flexural strength flexural modulus, dynamic impact strength, and yield strength of the composite while decreasing the elongation at break values. In addition, both TPU types and filler contents significantly affected the densities of V-TPU and R-TPU. The TPUs type, filler content, and cycle-rpm affected Taber’s abrasion resistance values. Weight loss, which increased with the number of cycles for the control samples, decreased with increasing wood flour content. This study aimed to provide an overview of the effect of the wood flour content in the manufacturing of thermoplastic-reinforced composites and to provide a basis for further research and development efforts.

Influence of the Addition of Palm (Borassus Aethiopum Mart.) Fibers on the Durability of Compressed Earth Blocks

This study aims to determine the influence of the content and length of the palm (borassus aethiopum mart.) fibers on the physical, mechanical and thermal properties of Compressed Earth Blocks (CEB). Three fiber contents (0.2%, 0.4% and 0.8%) of different lengths (10 mm, 20 mm, or 40 mm) were used to make CEB. CEB with 0% fiber content were manufactured to serve as control samples. CEB specimens stabilized with palm fibers or not were subjected to various tests according to standard XP P 13-901 for the determination of the following properties: dry density, water absorption, dry compressive strength, abrasion resistance and thermal conductivity. The results show that the dry density of CEB decreases from 4% to 7% when the content and length of the fibers increase respectively from 0.2% and 10 mm in length to 0.8% and 40 mm in length. The water absorption of fiber-containing CEBs ranges from 14% to 22% with increasing fiber content and length. The results also indicate that the mechanical and thermal properties are improved for well-chosen fiber contents. Thus, the dry compressive strength of the fibers increases by more than 13% for a fiber content of 0.2% and a length of 10 mm compared to CEB with 0% fibers. On the other hand, the optimal abrasion resistance values are obtained for a fiber content of 0.4% and a length of 40 mm. For all CEBs, the thermal conductivity values vary from 0.51 W/mK to 0.38 W/mK when the fiber content varies from 0.2% to 0.8%. Overall, palm fiber content has a greater influence on the measured physical, mechanical and thermal characteristics than fiber length.

Heavy aggregate and different admixtures efffect on parquets: chrome, magnetite, and quartz-based surface hardener

This paper presents the mechanical and micro-structure results of concrete parquet blocks. The blocks were generated by utilizing the same part in the bottom part and by substituting different proportions (40%, 30%, 20%, and 10%) of heavy aggregate like chromite aggregate, magnetite aggregate, normal aggregate, and surface hardener in the upper part. The parquet sample tests were conducted on TS 2824 EN 1338. The test outcomes indicated that utilizing diverse aggregate and chemical materials boosted the abrasion resistance, 40% magnetite and quartz-based concrete parquet block samples demonstrated the best abrasion resistance values. Also, the minimum amount of mass loss was discovered in the samples that possess high water absorption at the freezing-thaw test. The different material substitutions in the sheet of the surface of the concrete parquet block samples altered the tensile strength of the samples, even though they did not bring about an outstanding variation in the compressive strength of the concrete parquet samples.

Usability of Trabzon stone as a natural building stone and aggregate

This study investigated the suitability of Trabzon stone, which is used as a building stone in many areas in and around Trabzon province, as an aggregate. It was found that the uniaxial compressive strength values of the samples taken from the quarry were 87-130 MPa, P-wave velocities were 5048-5642 m/s, density value was 2.58 g/cm3, apparent porosity values were 2.77-4.54%, water absorption values by weight were 1.04-1.78% and water absorption value by mass was 2.0%. Weight loss in the freeze-thaw test was 0.36%, weight loss in the wet-dry test was 0.22%, loss in the magnesium sulfate test was 13%, Los Angeles fragmentation resistance in coarse aggregate was 22%, abrasion resistance value was 18% and methylene blue value was 0.9%. When the results were analyzed, it was found that the mass water absorption rate and the magnesium sulfate test results were above the values required by the standards. Although these rocks are used as marble, it has been determined that the waste material is not suitable for use as ballast, crushed stone, stone fill, pere, and masonry for road and concrete construction. Despite this result, it is necessary to investigate the usability of materials from other marble quarries in the region as aggregates.

Cigarette smoke uptake by different woven fabrics: Analysis of mechanical and colour properties

AbstractAlthough the impact of smoking tobacco on human health is well understood, less is known about the effects of tobacco smoke on cotton, viscose and polyamide fabrics. In this study, tobacco smoke was applied to fabric samples to investigate the effects of tobacco smoke on their mechanical and colour properties. For this purpose, tobacco smoke was pumped into a mechanism consisting of a glass box, in which cotton, viscose and polyamide fabrics were placed in a suspended position. The fabric samples were treated with tobacco smoke for 1 or 2 months. The samples were evaluated in terms of tensile and tear strength, elongation at break, as well as pilling and abrasion resistance values. A colour measurement test was used to investigate the withering effect of tobacco smoke, and Fourier Transfer–Infrared analysis was performed to examine the chemical changes. The tensile strength values in the warp direction were 419.34, 404.62 and 421.78 N without treatment and after 1 and 2 months of tobacco smoke treatment, respectively, for the cotton woven fabric. Furthermore, for woven cotton fabric, the L* value decreased from 93.8 to 78.7 after being treated with tobacco smoke for 2 months. As a result of this study, it was determined that tobacco smoke has no effect on the tensile strength properties of fabrics, causes changes to pilling and abrasion resistance values, and adversely affects the colour properties of fabrics.

Mechanical and Chemical Resistance of UV Coating Systems Prepared under Industrial Conditions.

In the upcoming years, it is expected that more furniture will be built from honeycomb panels due to the growing demand for lightweight, long-lasting furnishings. High-density fiberboard (HDF), previously used in the furniture industry as back walls in box furniture or drawer components, has become a popular facing material used in the production of honeycomb core panels. Varnishing the facing sheets of lightweight honeycomb core boards with the use of analog printing technology and UV lamps is a challenge for the industry. The aim of this study was to determine the effect of selected varnishing parameters on coating resistance by experimentally testing 48 coating variants. It was found that the interactions between the following variables were crucial in achieving adequate resistance: lamp power, the amounts of varnish applied, and the number of layers. The highest scratch, impact, and abrasion resistance values were observed for samples with optimal curing provided by more layers and maximum curing with 90 W/cm lamps. Based on the pareto chart, a model was generated that predicted the optimal settings for the highest scratch resistance. Resistance to cold liquids made with a colorimeter increases with lamp power.

Determination of The Effect of Dyeing and Finishing Processes on Physical, Mechanical, Handle, Comfort and Functional Properties of Cotton Knitted Fabrics

As it is known, the most widely used dye class for dyeing cotton fabrics is reactive dyes. However, the reactive dyeing process itself and various finishing processes applied after dyeing affects the physical, mechanical, handle, comfort and functional properties of the fabrics. Therefore, the main aim of this study was to determine the dyeing and finishing processes on the quality-performance characteristics of the cotton knitted fabrics. For this aim, physical (weight, wale/course density), mechanical (bursting strength, pilling, abrasion resistance), handle (bending rigidity), comfort (thermal comfort, air permeability, water vapor permeability) and functional (Ultraviolet protective functionality and flame retardancy of the fabrics) properties of fabrics were tested before and after dyeing and finishing processes. Fabric weight and bursting strength values increases after dyeing and finishing processes due to the shrinkage of the fabrics during wet processing. On the other hand, the pilling and abrasion resistance values ​​of fabrics are not significantly affected by dyeing and finishing processes. Another important result obtained is that the bending length and bending stiffness of the fabrics decrease after dyeing/finishing processes. The thickness values ​​of the fabrics decrease after dyeing-finishing processes and therefore the thermal resistance decreases. It was observed that the air permeability of the fabrics significantly decreased after dyeing-finishing processes. However, the water vapor permeability of the fabrics was decreased very slightly after dyeing and finishing processes. UPF ratings were increased after dyeing and finishing processes.
 Keywords: Cotton, dyeing, color, functionality, permeability

Ce-loaded silica nanoparticles in the epoxy nanocomposite coating for anticorrosion protection of carbon steel

PurposeThis study aims to explore how the inhibitor-loaded nanocontainers can be used in the epoxy coating for protection of steel against corrosion. A self-healing anticorrosive coating can be easily fabricated by embedding the inhibitor-loaded nanocontainers into the epoxy coating matrices. For this purpose, first, cerium (a catholic corrosion inhibitor) is encapsulated into silica nanoparticles (SiO2@Ce). Thereafter, an epoxy nanocomposite coating has been prepared on steel substrate using these SiO2@Ce nanoparticles as nanofillers.Design/methodology/approachTo examine the effect of SiO2@Ce nanocontainers on mechanical properties of epoxy coating, the abrasion resistance, impact resistance and adhesion strength of coating have been evaluated. To reveal the effect of SiO2@Ce nanocontainer on corrosion behavior of epoxy-coated steel, the electrochemical impedance spectroscopy (EIS) has been conducted in NaCl solution.FindingsTransmission electron microscopy and scanning electron microscopy/Energy-dispersive X-ray spectroscopy analyses indicate that Ce3+ cations have been successfully loaded into the surface of silica nanoparticles (at the content of approximately 2 Wt.%). Mechanical tests of epoxy nanocomposite coatings indicate that the nanocomposite coatings with nanoparticles content of 2.5 Wt.% provide the highest values of abrasion resistance, impact resistance and adhesion strength. EIS results show that the presence of SiO2@Ce3+ nanocontainers increases both coating resistance and polarization resistance. Along with the improvement the coating barrier performance, Ce inhibitor plays an important role in improving the anticorrosive performance at the steel–electrolyte interface.Originality/valueThe application of self-healing epoxy/SiO2@Ce nanocomposite coatings for the protection of carbon steel is very promising.

Assessment of some characteristics, properties of a novel waterborne acrylic coating incorporated TiO2 nanoparticles modified with silane coupling agent and Ag/Zn zeolite

Effect of rutile TiO2 nanoparticles modified with 3-(trimethoxysilyl) propyl methacrylate silane - TMSPM (m-TiO2) and Ag/Zn zeolite on the properties, and durability of acrylic waterborne coatings was studied. The obtained results indicated that m-TiO2 nanoparticles and Ag/Zn zeolite could disperse regularly in the acrylic polymer matrix. Consequently, the acrylic coating's abrasion resistance was improved in the presence of m-TiO2 or/and Ag/Zn zeolite. The acrylic coating's abrasion resistance depended on the content of m-TiO2 nanoparticles as well as the initial TMSPM content for modification of rutile TiO2 nanoparticles. The abrasion resistance of the m-TiO2 nanocomposite coating was higher than that of the unmodified TiO2 nanocomposite coating. The acrylic coating filled by 2 wt% TiO2 modified with 3 wt% TMSPM had the highest abrasion resistance value, leveling off at 187.2 L/mil. The abrasion resistance of acrylic coating filled by m-TiO2 reduced with increasing too high m-TiO2 nanoparticles content and using initial TMSPM content in high level for TiO2 modification. The starting temperature of weight loss of acrylic coating filled by m-TiO2 was lower than that of the neat acrylic coating. In comparison with the m-TiO2 nanoparticles, the Ag/Zn zeolite particles showed a lower improvement for acrylic coating properties, i.e. abrasion resistance, weathering durability, but the Ag/Zn zeolite particles expressed an excellent antibacterial activity. Hence, combination of the m-TiO2 nanoparticles and Ag/Zn zeolite particles could enhance the acrylic waterborne coatings' properties. The acrylic coating filled by 2 wt% m-TiO2 nanoparticles and 1 wt% Ag/Zn zeolite particles illustrated high abrasion resistance, good weather durability, and superior antibacterial activity for both of E. coli and S. aureus. This coating is promising for environmental friendly building materials application.

The homogenous alternative to biomineralization: Zn- and Mn-rich materials enable sharp organismal \u201ctools\u201d that reduce force requirements

We measured hardness, modulus of elasticity, and, for the first time, loss tangent, energy of fracture, abrasion resistance, and impact resistance of zinc- and manganese-enriched materials from fangs, stings and other “tools” of an ant, spider, scorpion and nereid worm. The mechanical properties of the Zn- and Mn-materials tended to cluster together between plain and biomineralized “tool” materials, with the hardness reaching, and most abrasion resistance values exceeding, those of calcified salmon teeth and crab claws. Atom probe tomography indicated that Zn was distributed homogeneously on a nanometer scale and likely bound as individual atoms to more than ¼ of the protein residues in ant mandibular teeth. This homogeneity appears to enable sharper, more precisely sculpted “tools” than materials with biomineral inclusions do, and also eliminates interfaces with the inclusions that could be susceptible to fracture. Based on contact mechanics and simplified models, we hypothesize that, relative to plain materials, the higher elastic modulus, hardness and abrasion resistance minimize temporary or permanent tool blunting, resulting in a roughly 2/3 reduction in the force, energy, and muscle mass required to initiate puncture of stiff materials, and even greater force reductions when the cumulative effects of abrasion are considered. We suggest that the sharpness-related force reductions lead to significant energy savings, and can also enable organisms, especially smaller ones, to puncture, cut, and grasp objects that would not be accessible with plain or biomineralized “tools”.

A Comparative Evaluation of Abrasion Resistance of Three Commercially Available Type IV Dental Stone, Dried using Three Different Drying Techniques - An In vitro Study.

Background:The microwave technique of drying dental stone to achieve improved hardness and strength has been suggested in recent years. However, its effect on the wear properties of dental stone has not been thoroughly examined.Aim:The present study was conducted in vitro to determine the abrasion resistance of three commercially available Type IV dental stones using three different drying techniques.Materials and Methods:A total of 180 samples were prepared from 3 Type IV dental stones; namely Eliterock, Zhermack (Italy), Kalrock, Kalabhai industries (India), and Gyprock (Rajkot, India). Samples were subjected to drying in open air for 2 h, hot air oven at a temp of 230°C for 1 h and microwave oven for 5 min at 900Watts. Abrasion resistance was determined using a customized metallic abrasion resistance tester.Results:Microwave oven drying produced samples with increased abrasion resistance values when compared to samples dried in hot air oven and air-dried specimens. Eliterock showed significantly higher mean abrasion resistance values followed by Kalrock and Gyprock.Conclusion:Drying type IV dental stone in a microwave oven at 900W for 5 min increased the abrasion resistance within short time.

Preparation of thermoplastic polyurethane-based biocomposites through injection molding: Effect of the filler type and content

The effects of lignocellulosic filler type and filler loading levels were investigated relative to selected properties of thermoplastic polyurethane (TPU)-based composites. Teak wood (TK), rice husks (RH), and microcrystalline cellulose (MCC) were used as lignocellulosic fillers at 15 wt% and 30 wt% filler loading levels. Test specimens were manufactured using both extrusion and injection molding, except for abrasion resistance samples that were manufactured using a compression molding process. Density, tensile, flexural, and impact properties, and hardness and abrasion resistance values, of the specimens were determined. The composites’ morphology was studied using scanning electron microscopy analysis; results showed all filler types and filler loading levels were affected by the TPU’s density and mechanical properties. The TPU composites were successfully produced using TK, RH, and MCC as lignocellulosic fillers. Regardless of filler type, addition of 15% filler to TPU yielded excellent mechanical properties. With 30% MCC filler, composite properties increased due to their higher surface area, while properties of TK- and RH-containing specimens were, at 30%, reduced. There was a proportional correlation between hardness and modulus, with both increasing with a rising filler loading level. Abrasion resistance of TPU decreased with the presence of filler. Regardless of filler type, abrasion resistance continued to drop at higher filler loading levels. Scanning electron micrographs showed better MCC distribution in the TPU matrix.

Mechanical and Thermal Properties of Waterborne Polyurethane Coating Modified through One-Step Cellulose Nanocrystals/Graphene Materials Sols Method

Developing multifunctional coatings with excellent mechanical and thermal properties is highly desirable for wood-based composite application. The recent development of waterborne coatings for wood products suggests that a promising thermosetting material needs to also have properties like low volatile organic contents (VOCs), hardness, and fast curing. The cellulose nanocrystals/graphene materials (CNC/GM) sols were prepared through the one-step method as the thermally conductive and reinforced modifier for preparing waterborne polyurethane (WPU) coatings. The influence of this modifier on the thermal and mechanical properties such as thermal conductivity, abrasion resistance, and adhesion of WPU coatings was investigated. The results indicated that adding CNC/GM sols increased the hardness, abrasion resistance, and thermal conductivity of the WPU coatings, and meanwhile maintained the coating adhesion at the highest grade (level 1). The highest abrasion resistance value of 0.023 g/100 r was obtained for the modified WPU coating when the addition of GM was 3%.

Abrasive wear behavior of austempered ductile iron with niobium additions

Carbidic Austempered Ductile Iron (CADI) microstructures containing eutectic carbides can be produced by the addition of carbide stabilizing elements, such as chromium. Carbides formed from the addition of Cr are eutectic of M3C type. The presence of such hard phases can enhance the abrasion wear resistance of ductile iron. A new CADI can be produced by the addition of Nb. Niobium carbide particles are formed in the beginning of solidification and remain stable once they are insoluble in solid iron matrix. The dry sand abrasive wear resistance of ductile irons alloyed with 1.0, 1.8, and 2.4 wt% Nb were tested in both “as-cast” and “heat treated” conditions using standard ASTM G65. Results were compared to abrasive wear data obtained on ductile iron alloyed with 1 wt% Cr, CADI (1 wt% Cr), and the basic composition of iron without carbide stabilizing elements. In the “as-cast” condition, the addition of Nb did not lead to a reduction in wear, while CADI with Nb is a promising substitute for CADI with Cr addition, because both materials showed very similar values of abrasion resistance. Micro-ploughing and micro-cutting mechanisms were observed on the worn surfaces of ductile irons. Abrasive wear resistance of these alloys was correlated with the volume fraction of carbides.

The effect of ultraviolet‐curable water‐borne polyurethane acrylate binder concentration on the printing performance of synthetic leather

In this paper, synthetic leather samples were screen printed with pigmented pastes including two types of photoinitiators and three different concentrations of ultraviolet (UV)‐curable water‐borne polyurethane acrylate binder. The curing process was conducted under different combinations of lamps (gallium, mercury, gallium/mercury and gallium/gallium/mercury) at three power levels. Abrasion resistance, crock fastness, hardness and colour strength were investigated. Chemical changes in the clear and pigmented film structures because of UV curing were analysed by Fourier Transform‐infrared spectroscopy measurements. In hardness measurements, the highest hardness values were obtained with clear and pigmented formulations which have the highest solid content (57%). In colour measurements, higher K/S values were obtained in samples printed with the formulation having a binder concentration of 46%. Wet crock fastness values improved as the energy level increased during curing, and the highest values were obtained with a formulation which had a binder concentration of 57%. Greater amounts of binder in the formulations and increased amounts of energy applied to the surface during curing increased the hardness value of the prints, thus better abrasion resistance was obtained. Overall results suggested that the highest hardness, crock fastness and abrasion resistance values were obtained with the formulation with a binder concentration of 57%. However, for ease of application, printing efficiency and colour strength, the formulation with a binder concentration of 46% is recommended for printing, and curing under consecutive passes with gallium and mercury lamps at 120 W/cm is proposed in terms of energy efficiency and printing performance.

FeCrMnNiCSi Coating on Grey Cast Iron FC 25 Variable Gas Pressure on Thermal Arc Spray Method

One of the important components of motor fuel engine is cylinder liner. There is a compression and friction combustion process with a piston that produces mechanical energy in cylinder liner. This process introduced several problems that often arise, such as wear reducing because the piston is moving back and forth continuously causing gas leakage so that compression pressure is reduced. To prevent such damage it is necessary to coat the metal with other material that has better wear resistance. This study used FeCrMnNiCSi coating material deposited on Gray cast iron FC 25 by thermal arc spray method to analyze the influence of pressure air variation on morphology and mechanical properties. SEM analysis showed that the higher pressure on the coating process results smaller particles thereby decreasing the porosity. Roughness testing also showed a decrease in the higher pressure, at a pressure of 6 bar of 127.333 μm. Microhardness showed that the 6 bar pressure indicating hardness was 639.8 HV. At 6 bar pressure also obtained the highest abrasion resistance value is 29.66 rotation / mg. The value of adhesion strength in the 4 bar pressure variables shows the optimum value compared with other pressure variations of 15.02 MPa.
 Keywords: cylinder liner, thermal arc-spray, pressure ambient

Characterization of the main types of marble extracted in the area of Macael (Almeria, southeastern Spain) and its historical importance

The marble from Macael is one of the most important ornamental stones found in Spain. It has been used not only as a building material but also as a decorative element, especially the type known as "White Macael". There is evidence of its use dating back over 4000 years. One of the most prominent examples is the Courtyard of the Lions in the Alhambra (Granada), but it is also possible to see some elements in the Roman amphitheatre of Mérida (Badajoz), in Italica (Sevilla), in the palace of Medina Azahara (Córdoba) and in the Royal Palace of Madrid, amongst dozens of palaces and churches throughout the country. In this study we describe the use that this material has had throughout history and the main features and properties of the different varieties of "White Macael", "Grey Macael", "Anasol" (calcite marbles) and "Yellow Macael" (dolomitic marbles). They all have mineralogical, physical and mechanical features that make them suitable for almost all uses. Calcite marbles have porosity, absorption and density values lower than dolomite marbles, whilst the latter have more resistance to compression, similar flexural strength under concentrated load, and lower resistance to breaking load at dowel hole than the calcitic marbles. The values of abrasion resistance are also better in the dolomite marbles, whilst the slip resistance is similar in all cases. As far as decay is concerned, the dolomitic marbles, with the exception of the variety Amarillo Triana, suffer more in the frost resistance test but less by the action of salts, with the exception of the White Macael Rio (calcitic) which is the variety that has less alteration. Regarding the status of the stone sector in the region, it is noteworthy that, despite a 60% drop in sales in the domestic market, exports in 2012 increased by 49% compared to the previous year. The data we present provides increased knowledge of one of the most common building materials in our country with the aim of optimizing its use by marketing companies and by consumers.

THE ABRASION OF AL-SI COATINGS WITH DIFFERENT SILICON CRYSTAL MORPHOLOGY, APPLIED IN AUTOMOTIVE SILENCERS

This paper compares the abrasibility of aluminium-silicon coatings with silicon crystals of various forms. The tests were performed on Al-Si coatings with the chemical comp67890-osition corresponding to that of hypoeutectic and peritectic silumins (6-10wt% Si), manufactured by hot-dipping on type X2CrTi12 steel and by cold cladding with 60% cold reduction on AlMn1Cu alloy. The hot-dip coatings deposited on X2CrTi12 steel were investigated as made and after a two-stage heat treatment: 420oC/2h/water and 120oC/2h/air. The morphology, shape, and size of silicon crystals in the coatings were studied under a microscope and with the image analysis technique (determining the shape factor among other parameters). Image analysis was also applied to the evaluation of abrasive wear resistance of the coatings using a ball wear test. Their adhesion strength was tested with the scratch test method. The test results indicated that the change in Al-Si coating silicon crystal morphology (from large sharp edged and needle-like to smaller rounded particles) was heat induced, which, compared to the pre-treatment condition, lowered abrasion resistance values and produced a more uniform abrasion loss. This condition was regarded as more desirable in terms of maintaining the coating continuity during drawing, with no risk of spalling. It was also demonstrated that clad Al-Si coatings could provide an alternative solution for the widely used hot dip coatings on steel sheet.

Spatial trends in the wind abrasion resistance of cultivated machair soil, South Uist, Scottish Outer Hebrides

The machair is a low-lying coastal grassland system with internationally recognised conservation importance, found only in parts of northern and western Scotland and Ireland. Machair soils are exposed to some of the highest mean wind-speeds in the UK and are susceptible to aeolian erosion. Samples of machair soils were collected from three transects perpendicular to the coast. A simple rotary sieve was used to quantify soil wind abrasion resistance (WAR) of the collected samples. WAR is directly linked to the threshold velocity at which sediment removal is initiated on exposed soil. Sieving subdivided the samples into erodible, potentially erodible, and non-erodible fractions and permitted testing of differences between the fractions. Physical and chemical tests were employed to characterise soil samples and fractions, and in a novel approach, FTIR spectroscopy allowed visualisation of the changes in soil composition along the transects. Principal component analysis and pruned regression trees were employed to model wind abrasion resistance from soil properties, including the FTIR spectra. Results indicated intra- and inter-site variability in wind abrasion covering the full range of possible wind abrasion resistance values. Strong correlations were found between wind abrasion resistance and soil organic matter concentrations, persistence of water repellence, mean particle size, arsenic concentration, water content at time of sampling, and sand mineralogy. For wind abrasion resistance greater than 10 regression tree analysis was capable of predicting whether actual wind abrasion resistance values were low (<15), medium (>15 and <35), or high (>35).

Concrete properties containing fine aggregate marble powder

The rapid growth of the marble industry introduces concerns regarding the negative impact of marble quarrying on the environment, because the cutting of marble creates sludge. The incorporation of marble sludge (powder) into concrete and cement-based products would make significant environmental and economic contributions. This study aims to develop a concrete mixture with maximum marble content that has strength properties comparable to that of the non-marble reference concrete (without marble powder), as opposed to developing a marble powder concrete with maximum compressive strength. The main purpose is to replace sand with marble powder in concrete because such a mixture will be environmentally friendly and economically feasible. The concrete samples are produced by replacing sand with marble powder at 10%, 20%, 30%, 40%, 50% and 90% by volume. The compressive strength values are determined after 7, 28 and 90 days with splitting tensile strength values at 28-th day including water absorption and abrasion resistance values. A feasibility evaluation is performed using parameters such as fresh concrete, compressive strength, sorptivity, abrasion resistance, and estimated cost. Based on the feasibility evaluation it is shown that using up to 40% marble powder in concrete is suitable in accordance with the requirements.