Apparent Specific Gravity Research Articles

Use of Various Industrial and Eggshell Wastes for the Sustainable Construction Sector

The alternative composites’ production alleviates the serious problem generated by global warming. Methods to reduce the amount of cement used in concrete production, for example, are being investigated to determine how to reduce carbon dioxide emissions in many applications. Egg shells and various industrial wastes, which are recommended to use in the construction sector at an appropriately high rate, also cause serious environmental damage. Bottom ash (BA) and marble powder (MP) wastes are used today in civil engineering applications. In addition, it is important to increase the use of eggshells due to their rich calcium carbonate content. In this work, BA and MP wastes were blended with eggshells to produce cement paste composites. Two different sets of composites were prepared during this study. The composites were prepared with cement (80%), BA (20%), and MP (20%) wastes by weight with 0.3%, 0.75%, 1.5%, and 2.5% eggshell waste. The fresh (flow table), physical (dry unit mass, apparent specific gravity, and porosity), mechanical (unconfined compressive strength and flexural strength), and durability (water absorption, seawater resistance) tests were conducted. According to the experimental results, the composites can be classified as lightweight construction materials. The test results showed that 0.75% eggshell by weight of cement in bottom ash and marble powder can be used as an optimum value for better performance. The bottom ash mixtures groups are higher water absorption and porosity values when referring to the marble powder mixture groups. The highest compressive strength value was found at 56.03 MPa in the MP mixture group and 52.79 MPa in the BA mixture groups with these optimum eggshell combinations at 56 days. The MP mixture group showed better resistance to seawater when referring to the bottom ash blended mixtures. Laboratory-produced composites are possible candidates for cost-effective and environmentally friendly building materials. The eggshells have a promising alternative binder for concrete in the near future and they are utilized together with industrial wastes such as BA and MP in sustainable concrete construction.

Study on Manufacturing of Bricks by Using Waste Foundry Sand

The main objective of this project is to utilize waste foundry sand (WFS) from foundry industry in manufacturing of bricks. The entire process of combining clay mixtures, forming of bricks, drying and firing was done with local conditions. With minimum process it was possible to introduce up to 30% WFS in clay bodies to produce bricks of desirable properties. The minimum average wet compression resistance of 5.54Mpa, and maximum average water absorption of 20.76% was obtained for bricks containing 30% WFS, when fired at 900 C. There was insignificant difference in apparent porosity, water absorption, and specific gravity of bricks containing WFS, when compared to commercial bricks. The addition of WFS reduced the bulk density of the bricks, which has also caused reduction in compressive strength. WFS bricks can be classified as class II bricks, based on recommendations of IS 1077 standard specification. These bricks can be used in single storied load bearing structures, and also in the construction of infill walls in multi-storied framed structures.

The Effect of Vacuum Forming on the Quality of Refractory Materials

Various designs of furnaces for melting alloys are used in the foundry industry. Regardless of their design, they have one common detail, which is the lining of their interiors with refractory materials. This component in the design of a metal-melting furnace has a very important task—to protect the rest of the furnace assemblies from thermal and mechanical damage. Continuous technical progress and the quality requirements of casting production produce increasingly higher demands for refractory materials in connection with their development as well. The article presents the results of an innovative method of vibratory compaction of refractory material (high-alumina aluminosilicate) using reduced pressure. The analysis presents a comparative study of two methods used for forming refractory materials, i.e., the application of the mentioned innovative method and the classical (standard) method of compaction by vibration only. The effects of the introduced modification in the manufacture of ceramic shapes were evaluated by means of the material’s resistance to thermal shock, linear expansion, and dimensional change due to firing, apparent density, open porosity, and apparent specific gravity, determination of total pore volume and pore size distribution by mercury porosimetry, and slag resistance. The tests performed indicate that the procedure of lowering the pressure during the vibratory compaction of the refractory material creates a more homogeneous structure with a smaller number and size of pores. This makes it possible to improve most of the parameters that determine the quality of the refractories used for the linings of the foundry furnace.

New procedure to estimate soil field capacity based on double ring infiltration data

Many models have been proposed to explain the water infiltration curve in soil, but according to the studies we have done so far, no model can simultaneously estimate the field capacity (FC) and soil hydraulic conductivity (K). The aim of this research is to present a new model that is defined based on the dynamic balance of water-soil-time and is able to estimate FC and soil hydraulic conductivity using cumulative field infiltration data. The studies were carried out in Varamin region with an area of 1370 square kilometers. For the penetration test, first, seven sides (A, B, C, D, E, F and G) were selected in 7 areas of agricultural land and with a double ring with an outer diameter (70 cm) and an inner diameter (30 cm) became. Also, to determine the soil texture, apparent specific gravity, PWP and FC, soil sampling was done at the depths of 0–10 and 20–30 cm. To determine FC moisture, pressure (−10 kPa) was used in a pressurized membrane device, and to determine volumetric moisture in PWP, sieved samples were placed on ceramic plates. Using a spray, the samples were wetted, so that they reached the saturation level, and the pressure was set to 1500 kPa. Examining the FC values showed that the maximum value of FC in site F (clay loam texture) is equal to 14.73 cm and the lowest value in site G (sandy clay loam texture) is equal to 6.8 cm by the model estimated by the results obtained in Laboratory confirmed. Meanwhile, the minimum saturated hydraulic conductivity of soil at site A was estimated to be 0.06 cm/min and the maximum at sites D and F was 0.28 cm/min. Time constant (Ksh) has shown completely different water infiltration rate in the first term of the model (Rfksh) compared to the second term of it (K), and no obvious relation has detected between them. But, their summation (k+Rfksh) was always equal to the maximum infiltration instantaneous rate (T→0). The research results showed that using the new model, the FC value varies between 6.8 and 14.73 cm. Also, the minimum and maximum instantaneous speed of water infiltration occurred in the site. An equal to 0.621 and in site D equal to 1.735 cm/min. The results of fitting the penetration model on cumulative penetration data showed that R2 varies between 0.994 and 0.999 and RMSE between 0.116 and 1.197. Therefore, the model is able to describe the penetration data well.

Mechanical properties of synthetic aggregate pelletized by waste concrete fines in Vietnam

Due to rapid industrialization and economic growth, the generation of construction and demolition waste (CDW) from the activities of demolishing buildings is increasing in Vietnam. The Vietnamese Government has regulations on recycling and collecting CDW for reuse, recycling to environmental protection through Circular No. 08/2017/TT-BXD in 2017, and Directive 41/CT-TTg in 2020. Waste concrete fines (WCF) are generated during demolishing process or crushing of CDW materials. To save natural resources and increase the recycling rate, a disc pelleting technology has been used to recycle WCF. The pellet machine has a disk with 1.5m of diameter and 0.3m of depth; tilted at an angle of 55 degrees and the rotation speed from 15 to 22 rpm; the capacity is 0.5 to 0.8 tons per hour. This paper presents the results of pelletizing WCF research to produce synthetic aggregate (SA). The SA pelletized by WCF and cement had an apparent specific gravity of 2.45 – 2.55 g/cm3, a dry bulk specific gravity of 1.85 – 1.95 g/cm3, a crushing value of 19.2 – 29.9%, a LA (Los Angeles) value of 23 – 33% and water absorption around 13.2%. The mechanical properties of SA meet the requirement of TCVN 11969:2018, recycled aggregate type II for concrete.

An Experiment on Apparent Specific Gravity and Settleable Degree of Fire Extinguishing Agent according to Durable Years of Regional Powder Extinguisher

For powder extinguishing agents based on the useful life of the powder extinguisher, a powder extinguisher with a elapsed life of 6-10 years was collected from market, factory, and apartment houses to experiment with changes in volume by appearance and sedimentation, and to examine digestive characteristics. As a result of the study, the first, second, and third arithmetic mean analysis of the apparent specific gravity experiments from 6 to 10 years of use, showed that the total arithmetic average of three experiments in the market area with an 8-year useful life was 127mL. In 2012, the average arithmetic average of three experiments in multi-family housing with a 10-year useful life was 131mL, which was found to be inappropriate. Second, in the experimental value for sedimentation, it was found to be unsuitable in the 2012 sedimentation experiment on samples in the apartment area. In other words, the sedimentation test of the powder extinguishing agent should not occur within an hour, but the sample in the apartment complex area in 2012 was found to be defective. Third, the fire extinguisher needs to be strengthened to enable fire extinguisher maintenance and inspection because problems that cannot be used during initial fire suppression occur depending on the place of deployment, surrounding environment, age of use, and maintenance status.

Development of Microencapsulation-Hybrid Jig Separation Technique as a Clean Coal Technology

In this study, the microencapsulation-hybrid jig separation technique was developed to improve the separation efficiency of pyrite and coal in the particle size range of 1–4 mm where conventional jig separation becomes inefficient. A hybrid jig is a gravity concentrator combining the concepts of jig separation and flotation to stratify particles based on their apparent specific gravity. Meanwhile, microencapsulation—a technique that encapsulates target materials with a protective coating—was applied to render pyrite hydrophilic and improve its separation from hydrophobic coal. The results showed that the required time for separation in the hybrid jig (0.5 min) was shorter than in conventional jig (2 min). Moreover, the effects of particle size on separation efficiency were reduced when a hybrid jig is used. However, the separation efficiency of hybrid jig separation was lower than that of the conventional jig because attachment of bubbles occurred to both pyrite and coal, which are hydrophobic. Using the microencapsulation-hybrid jig separation technique, the separation of coal and pyrite was significantly improved (~100%) because of the formation of hydrophilic iron phosphate coatings on pyrite that limited bubble attachment. This means that microencapsulation-hybrid jig separation is a promising clean coal technology that not only enhances the separation efficiency of the hybrid jig but also passivates pyrite and limits AMD formation in the tailings/rejects.

Mechanical behavior of concrete containing recycled aggregates

Increased demand and decreased supply of aggregates for concrete production necessitate the search for new aggregate sources. Environmental features are increasingly being used to evaluate construction materials. Concrete recycling is becoming more popular since it conserves natural resources and reduces the need for disposal by using readily available concrete as a source of aggregate for fresh concrete. Several studies on the influence of recycled aggregate on the engineering qualities of concrete have been conducted. This investigation was carried out using the use of recycled aggregate as a form of modification. When it comes to the use of recycled aggregate, the percentage of recycled aggregate should be decided. This is because a large proportion of recycled aggregate would not allow for the achievement of the desired level of strength in the concrete. The purpose of the research is to evaluate the similarities and differences between natural aggregate and recycled coarse aggregate with regard to specific gravity, apparent specific gravity, absorption, and Los Angeles. In addition, the comparison of recycled aggregate with 0% replacement, 35% replacement, 50% replacement, and 65% replacement will be the emphasis of this study.

Exploitation of waste perlite products in lime-based mortars and grouts

Perlite is an amorphous mineral, coming from volcanic deposits and mainly consists of alumino-siliceous compounds. Perlite mining presents a low environmental burden, while during the last 60 years less than the 1% of the worldwide reserves have been exploited. During its industrial process, a significant number of secondary products derives and remain unexploited, inducing the environmental burden. The study focuses on exploiting two secondary products coming from the elaboration of perlite (named after D1S, D1C), in the Hellenic plant. These products have been used as pozzolans in the production of mortars and grouts. During the experimental part, nine mixtures where manufactured and tested, including five mortars and four grouts, where natural pozzolan was substituted by D1S and D1C. The fresh state properties of all mixtures were recorded, as well as their hardened ones, including shrinkage deformations, porosity, apparent specific gravity, water absorption coefficient due to capillary action, dynamic modulus of elasticity, flexure and compressive strength. From the correlation of the results, it was asserted that the partial or even total substitution of natural pozzolan by perlite secondary products, can positively influence the physical and mechanical properties of the composites. D1S seem to be an alternative pozzolanic material leading in mortars and grouts of enhanced properties. It maybe therefore concluded that the exploitation of perlite secondary products in the construction sector is feasible, leading to the development of effective, low-cost and environmentally friendly products for specific applications.

Characterization of granite mining waste for geotechnical purposes

Waste generation is part of any production process. Among productive sectors, the mining industry stands out in environmentally sustainable models due to the large volume of waste produced. Crystalline rocks, particularly granites, are highlighted due to their high mechanical strength and esthetic characteristics. The aim of this study was to perform a geological/geotechnical characterization of granite mining waste for geotechnical purposes. Samples of granite mining waste were collected at different waste disposal points. The following characterizations were performed: physical (apparent specific gravity, apparent absorption and apparent porosity), optical and scanning electron microscopy and mechanical characterization (uniaxial compressive strength test). All the samples analyzed exhibited physical indices and average values compatible with those recommended by international standards. Textural aspects, such as random muscovite concentration, forming aggregates, can explain the mechanical behaviour of the samples. In addition, based on the results obtained, the waste collected can be used in the riprap of hydraulic and construction projects that cross water courses and roadways.

Effects of magnetized municipal effluent on some physical properties of soil in furrow irrigation

Due to the water crisis, effluent reuse is an effective method in order to supply crop water requirements. In order to study the impact of treated and magnetic effluent on the soil properties, this research was conducted in randomized complete block design with three irrigation treatments; including "effluent", "magnetic effluent" and "normal water" in four replications. Soil samples were taken from two surface and subsurface soil layers and at the upper and the downstream of each furrow. Evaluating the apparent specific gravity of soil in different water quality treatments showed that this soil property was increased effectively at the upstream part of the furrow. Similar results were also observed in the field capacity but more fluctuations were observed. Simultaneously, effluent treatment showed decreasing effects on soil water holding capacity during the time, which can be attributed to the increasing of soil organic matters. It seems that the high fluctuations between different design blocks are related to the gravelly nature of soil. However, intensification or weakening effect of these changes was not even found by magnetic.

Reverse hybrid jig separation efficiency estimation of floating plastics using apparent specific gravity and concentration criterion.

We developed a technique called the reverse hybrid jig, an advanced physical separation technique that combines the principles of jig and flotation to separate floating plastics. This technique is a promising green technology that is more economical and environmentally friendly compared with the conventional flotation. Although the applicability of this technique to separate PP/PE have been reported, the index to illustrate the possibility of separation for the reverse hybrid jig is still not available. In this study, a reverse apparent concentration criterion (CC RA ) is proposed to estimate reverse hybrid jig separation efficiency. This modified concentration criterion can be calculated using the specific gravity (SG) of particle with attached bubbles called the apparent specific gravity (SG A ). To determine the volume of attached bubbles on plastic surfaces under water pulsation, a laser-assisted apparatus was used under various conditions, including plastic type, air flow rate, dosage, and type of wetting agent. The results of attached bubble volume measurements were used to calculate the SG A and CC RA . The estimated values were then compared with the results of reverse hybrid jig separation. It was found that higher CC RA resulted in better separation efficiency. In addition, an empirical linear equation for estimating the reverse hybrid jig separation efficiency is proposed.

PHYSICOCHEMICAL CHARACTERIZATION OF FERMENTED BOKASHI COMPOST PRODUCED ON FARM IN SOUTHERN BRAZIL

Bokashi is fermented organic compost capable of improving the physical, chemical, and biological conditions of the soils. The compost action in the agricultural production system is influenced by its preparation, resulting in products with different physicochemical characteristics. The study aimed to characterize bokashi produced on-farm and compare it with commercial products. The produced composts in southern Brazil were obtained through efficient microorganisms (EM), collected in an area of permanent preservation, and kefir. Two commercial composts were used for comparison (Plantae FertTM and Bokashi Sementes BrasilTM). Physical characteristics related to apparent specific gravity, water content, and water retention capacity and chemical characteristics related to nutrient contents, pH, and electrical conductivity were analyzed. For the physical characteristics, the mean and standard deviation were determined. The data from chemical parameters were submitted to the analysis of variance, and the means were compared by the Tukey test with 5% significance. Bokashi produced on-farm and commercial Bokashi showed similar physical characteristics. Commercial bokashi composts showed higher contents of nutrients than the composts produced on-farm. The analyzed composts showed adequate physicochemical parameters, with no factors limiting their use in agriculture.

Reconnaissance Study of Gypsum from the Fatha Formation as Raw Material for Production of Gypsum Powder in Shaqlawa Area, Erbil, Kurdistan Region, Iraq

The quality of gypsum rock as raw material from the Fatha Formation in Talajar Village in the Shaqlawa area for ground gypsum production was assessed. A total of three samples of gypsum were collected from different locations of the same horizon in the outcrop for comparing the chemical and physical properties according to the Iraqi Standard Specification 26-1988 and American Standard for Testing and Materials C471-16. The analyses of major oxides for the bulk gypsum samples especially the main components for gypsum (SO3, CaO, and combined water) showed good results and good purity. The apparent specific gravity and absorption of water were performed according to Iraqi Standard Specification 27-1988 at room temperature. These obtained data from chemical analyses and physical tests results revealed that the gypsum quality is in conformance with Iraqi Standard Specification requirements. The quality assessments from the study area show that the gypsum in the selected area is suitable as raw material for ground gypsum production.

EVALUATION OF THE PHYSICO-MECHANICAL PROPERTIES OF PLYWOOD PANELS AND LAMINATED VENEER LUMBER OF Pinus glabra Walt.

This work evaluated the potential of the species Pinus glabra for the production of laminated panels, as well as the effect of the density of the veneers and their combination on the quality of the product. The plywood and laminated veneer lumber were produced from two veneer density classes and the combination between them, namely: panels with veneers from 0.33 to 0.40 g/cm3; panels with veneers ranging from 0.41 to 0.48 g/cm3; and panels with veneers of 0.33-0.40 g/cm3 in the inner layer and 0.41-0.48 g/cm3 in the outer layer, resulting in 6 treatments. Phenol-formaldehyde was used as adhesive, whose formulation was 100 pbw of adhesive, 20 pbw of extender, 10 pbw of filler and 20 pbw of water, and applied at a grammage of 180 g/m². The pressing parameters were 1 MPa and temperature of 160ºC for 8 minutes. The evaluation of the quality of the panels was performed through tests of apparent specific gravity, static bending and glue line shear strength, according to European standards. The results presented that the production of panels, from the classification of veneers by densities and combination between them, provides gains in strength and stiffness. The parallel direction of the veneers (in LVL) provided gains in strength and stiffness when compared to panels produced with veneers perpendicular to each other (plywood), being, therefore, the most suitable for structural use. Finally, we have the conclusion that the species Pinus glabra has potential for producing laminated panels.

Evaluation of the Rocks of The Pila Spi Formation of Duhok Anticline For Building Stones – Kurdistan Region Of Iraq

The rocks of the Pila Spi Formation at the southern limb of the Duhok anticline have been evaluated for use as building stones. The geology of the area and examined rocks are described. Nine samples were collected and tested for physico-mechanical properties (total porosity, water absorption, saturation coefficient, apparent specific gravity, bulk density and uniaxial compressive strength). There was a remarkable variation between the samples in these properties, which showed very high significant relationships with each other. Samples were classified as frost-resistant. According to the Iraqi and American Standards, four samples were categorized as (low density/acceptable), three samples as (moderate density/recommended) and two samples as (high density/highly recommended). According to some classifications, the samples were (moderately strong) except for two of them were (strong), while all of them were (moderately strong) and (high strength rocks) in other classifications. The examined rocks are suitable for interior and exterior wall cladding and exterior fencing, as well as for decoration. Four of them are not suitable for building sections that require high load bearing or in places where they come into contact with water or soil, such as foundations, while only two samples are suitable. The quality and quantity of the rocks and the quarrying conditions encourage their exploitation for building stones, with the necessity of proper planning of the proposed quarry and special treatment during quarrying.

Optimisation of the Physical Properties of Rice Husk Ash in Ceramic Materials Using the Response Surface Methodology

Optimisation of the physical properties of rice husk ash (RHA) in ceramic materials was carried out using Response Surface Methodology. The independent variables, namely the firing temperature and residue content, were statistically combined in a Central Composite Design with the effects on water absorption, linear shrinkage, bulk density, apparent porosity and apparent specific gravity determined. Physical and microstructural analyses were carried out to obtain information on the processes that occurred within the ceramic materials. The results obtained were analysed to determine the optimum physical properties of the ceramic materials within the range investigated. The residue content had a significant influence (at 95% confidence level) on the bulk density, water absorption, apparent porosity and apparent specific gravity but not on the linear shrinkage. The firing temperature had a more significant effect on the linear shrinkage than on the residue content, so that when elevated it contributed to an increase in linear shrinkage. The optimum residue content and firing temperature to enhance physical properties within the range investigated were 5.85% RHA and 1029.64°celsius, respectively. These optimal conditions are expected to produce a ceramic material with a bulk density, linear shrinkage, apparent porosity, water absorption and apparent specific gravity of 1.64 g/cm3, 0.29%, 0.29 g/cm3, 18.26% and 2.11, respectively with a composite desirability of 100%.

Petrological Properties of Flat Stones from the Obongsan Mountain Quarry Used for Flooring in Ondol

The purpose of this study is to scientifically analyze the rocks of the Obongsan Mountain in Boseong, Jeollanam-do, which contains the largest extant quarry of Gudlejang (flat stone for heating) in Korea, and to scientifically determine the petrological characteristics of the area and the reasons for its use as a quarry. The rocks in the quarry are composed of light-green lapilli tuff, containing various types of lithic fragments and crystalline fragments in a vitreous matrix consisting of the fine feldspar crystals. The main constituent minerals were identified as quartz, plagioclase, mica, chlorite and opaque minerals. When the major element compositions were plotted on a Na2O+K2O versus SiO2 diagram, all samples were situated in the same compositional area as rhyolite. In addition, the result of magnetic susceptibility measurement also showed a similar range of values, of 1.30 ∼ 4.85 (×10<sup>-3</sup> SI), indicating that samples were fractionated from the same magma. Both rock types showed similar apparent specific gravity values of 2.32 ~ 2.60. In particular, plate-shaped joints are well developed in the Obongsan Mountain area, and many areas exhibit talus terrain. In conclusion, the rocks of this area is interpreted to used for a site of Gudlejang quarrying, because the rocks were easily obtainable due to the terrain characteristics, and their petrological properties made them suitable for use as Gudlejang stone.

KAMLIAL SANDSTONE AS AN AGGREGATE PROBLEM FOR CONSTRUCTION INDUSTRY, PALANDRI AZAD KASHMIR

Study area concedes the compressional stresses caused by the collision of Indian and Eurasian plates molded the northwest- southeast trending faults which are Riasi Fault (RF), Palandri Fault (PF), Godri Badshah Fault (GBF) and Chhechhan Fault (CF). This study intended to analyze the Kamlial sandstone as an aggregate problem for construction industry while sedimentary structure, stratigraphic sequence and geology of the study area were also destined. The study area comprised Nakar, Chhechhan, Holar, Tallian and Sarsawah of Palandri Azad Kashmir. The Impact value, Los Angeles Abrasion resistance, Specific gravity and Water absorption test were evaluated for kamlial sandstone. The samples were collected from Garata Sarsawa, Panjeera, Telyan, Kharran, Jabbri kass, Kand Gora, Parasgali, Garrala, Hollar, Chhechann and Nakar near Pallandri. Impact value of Kamlial Sandstone recorded 25.2, Abrasion Resistance of Kamlial Sandstones is 41.4 % which is less than AASHTO value i.e 50 percent. The Apparent Specific gravity initiate 2.1 percent which is less than ASTM standards i.e between 2.6-2.9. and the Water Absorption value recorded 2.24%. The results intimate that the Kamlial sandstone does not qualify ASTM specification for aggregate.

Chemical performance analysis of nanocellulose/boron-compound-reinforced hybrid UF resin

Urea–formaldehyde (UF) resin is the most important used adhesive in the production of wood-based composite panels, such as particleboard, medium-density fiberboard, oriented strand board and plywood. The aim of this work was to investigate the influence of nanocellulose, boric acid and borax on the chemical performance properties of UF resin. UF resin was reinforced with various loading levels of nanocellulose, boric acid and borax. Formaldehyde emission, gel time, solid content, viscosity, pH, specific gravity, shelf life and Fourier transform infrared spectra were evaluated as indicators of chemical performance. The findings showed that the formaldehyde emission of hybrid UF resin reinforced with nanocellulose/boron compounds decreased by up to 31.25%. The use of the reinforcement technique in the resin caused an increase in shelf life, viscosity and gel time but caused a reduction in the solid content of the resin. The apparent specific gravity of the resin was not influenced by the addition of nanocellulose/boron compounds. It was concluded that the chemical performance properties of UF resin could be enhanced by using proper nanocellulose, boric acid and borax loading levels. By using the reinforcement technique, it was possible to produce low-formaldehyde-emitting adhesives so that environmentally friendly products could be manufactured.