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Evaluation of Foundry Properties of Brahmaputra River Sand and its Prospects

Rana Md. Shohel, Shahriar Md. Shams, Alam Md. Sha, Hossain Md. Imam Sohel, Biswas Pradip Kumar, Zaman Mohammad Nazin

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 2

80--90

EN

The river system of the Bengal delta encompasses a huge amount of fluvial sand; however, no comprehensive studies were available on using this river sand in foundry industries. Hence, the present research evaluates the foundry properties of trans-boundary Brahmaputra River sand and its prospects for use in foundries. Several laboratory analyses have been performed to elicit the foundry properties using standard methods of foundry analysis, including XRD, XRF, TG-DSC, and FESEM. From the study, the sand contains mainly quartz with small amounts of feldspar, amphibole, chlorite, and mica, and exhibits a subangular to subrounded shape. The sand is dominated by SiO2 (67.81-69.97%) and lesser amounts of other oxides, and it is thermally stable within 1000 °C temperature. The grain fineness number (64-79), mineralogical, chemical, thermal, and foundry properties are suitable for non-ferrous metal casting without distortion. Further, the aluminum and zinc alloy casting with trials demonstrate their potential for use in the foundry industries. The outcomes of this study thus offer valuable information about utilizing Brahmaputra River sand for foundry applications.

2

Plastic waste reinforced with inorganic pigment from red stone in manufacturing paving block for pedestrian application

Sastrawidana D. K., Sukarta I. N., Saraswati L. P. A., Maryam S., Putra G. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 110, nr 2

49--58

EN

Purpose: This study was aimed to investigate the effectiveness of plastic waste as fine aggregates to partial replacement of sand reinforced with inorganic pigment from red stone to manufacture paving block for pedestrian application. This is an effort not only to reduce plastic waste in the environment but also as an innovative way to find out an alternative eco-friendly paving block material for public walkways with an attractive appearance while ensuring pedestrian comfort. Design/methodology/approach: Approaches were converted the plastic waste to plastic powder which is then used as fine particles to sand partial replacement. The red stone powder is used to give red color to the paving block surface. The paving block materials were completely mixed in a pan mixer and added water as much as 12% of the total mass of the materials used. The paving block was cast in a mold dimension size of 20 cm × 10 cm × 6 cm and pressed with a load of 6 tons using a pressing machine. The effect of natural river sand to plastic powder ratio and curing time on the compressive strength and water absorption were investigated. Findings: The study results confirmed that the replacement of sand with plastic powder decreased the compressive strength of paving block. By partial replacement of sand with plastic powder in the range of 10% to 50% by weight, the compressive strength and water absorption value of pavement after 30 days agitation were at range of 18.06-12.78 MPa and 4.28-3.25%, respectively. This value was still met the minimum requirement for pedestrian applications according to Indonesian National Standard. Research limitations/implications: Replacing sand up to 50% by weight with plastic waste produces paving blocks with compressive strength and water absorption suitable for sidewalks and pedestrians. It is needed to continue research in terms of durability tests in order to be comfortable with the practical use of the material. Practical implications: The use of plastic waste reinforced with red stone powder as fine aggregate makes it one of the alternative ways to reduce plastic waste in the environment and obtain eco-friendly paving blocks with an attractive appearance. Originality/value: It has been experimentally proven that replacing sand up to 50% by weight with plastic powder produces paving blocks that are suitable for pedestrians application. The addition of red stone powder pigment makes the color of paving block surface become more attractive appearance.

3

Identifying the pool-point bar location based on experimental investigation

Maatooq Jaafar S., Hameed Luay

Journal of Water and Land Development

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2019

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no. 43

106--112

EN

Morphological relationships of meander evolution in terms of hydraulic and geometric characteristics are essential for river management. In present study, an experimental based study of meander evolution was employed to develop a prediction formula for identifying the pool-point bar location by using the dimensional analysis technique and multiple nonlinear regressions. Through the experimental work on a race of the non-uniform river sand, a set of experimental runs have been carried out through combining different hydraulic and geometric parameters to produce different empirical conditions that have a direct impact on the pool-point bar location. Based on the experimental observations and measurements, the variation in pool–point bar locations could be interpreted to that the hydraulic and morphologic properties through the meander evolution were varied during the time causes the variations in the patterns of the pool-point bar formations accordingly. The developed formula was verified by using another set of the experimental data and tested with three statistical indicators. The predicted results indicated that the proposed formula had high reliability for practical estimation of the pool-point bar location. This reliability was tested by the statistical indicators, where the less values have been resulted for bias and mean absolute error (MAE), 0.0004 and 0.0110 respectively, whereas the higher values 0.935 and 0.930 are achieved for the Nash–Sutcliffe efficiency (NSE) and the determination coefficient R2, respectively.

PL

Morfologiczne zależności rozwoju meandrów, określane cechami hydraulicznymi i geometrycznymi, są ważne dla gospodarki wodnej. W przedstawionej pracy opisano eksperymentalne badania rozwoju meandrów celem uzyskania prognostycznego wzoru do określenia lokalizacji odsypiska z użyciem techniki analizy wymiarowej i wielorakiej regresji nieliniowej. Przeprowadzono serię eksperymentów nad przemieszczaniem niejednorodnego piasku rzecznego poprzez łączenie różnych parametrów hydraulicznych i geometrycznych, aby osiągnąć różne warunki doświadczalne, które mają wpływ na lokalizację odsypiska. Na podstawie obserwacji i pomiarów z doświadczeń zmienność lokalizacji można interpretować jako zmienność w czasie hydraulicznych i morfologicznych cech tworzenia meandru, które odpowiednio zmieniają położenie odsypiska. Uzyskany wzór weryfikowano, używając innego zestawu danych eksperymentalnych i testowano za pomocą trzech wskaźników statystycznych. Wyniki wskazują, że proponowany wzór ma dużą wiarygodność w praktycznym szacowaniu lokalizacji odsypiska. Wiarygodność tę sprawdzono za pomocą wskaźników statystycznych, w których uzyskano mniejsze wartości dla błędu systematycznego – 0,0004 i średniego błędu bezwzględnego (MAE) – 0,011, podczas gdy wyższe wartości osiągnięto dla współczynnika efektywności Nasha–Sutcliffe’a (NSE) – 0,935 i współczynnika determinacji R2 – 0,930.

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Investigation of Some Moulding Properties of a Nigerian Clay-Bonded Sand

Oke A. O., Omidiji B. V.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 3

71--76

EN

Moulding properties of Isasa River Sand bonded with Ipetumodu clay (Ife-North Local Government Area, Osun State, Nigeria) were investigated. American Foundry men Society (AFS) standard cylindrical specimens 50mm diameter and 50mm in height were prepared from various sand and clay ratios (between 18% and 32%) with 15% water content. The stress-strain curves were generated from a universal strength testing machine. A flow factor was calculated from the inclination of the falling slope beyond the maximum compressive strength. The result shows that the flowability of the samples increases from 18% to 26% clay content, its maximum value was attained at 26% and then it decreases from 30% to 32% clay content. The green compressive strength, dry compressive strength and air permeability values obtained from the mould samples were in accordance with standard values used in foundry practice. The x-ray diffraction test shows that the sand contains silicon oxide (SiO2), Aluminium oxide (Al2O3), and Aluminium silicate (Al6Si2O13). The mould samples were heated to a temperature of 1200 oC to determine the sintering temperature; fussion did not take place at this temperature. The results showed that the sand and clay mixture can be used to cast ferrous and non-ferrous alloys.

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Prędkość opadania ziaren piasków rzecznych

Popek Z.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2004

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Vol. 13, No. 1

13--23

EN

Results of analysis based on theoretical and empirical equations for determination of fall velocity in stagnant water for rive r’s sandy grains are presented in the paper. Based on investigation results of Albertson (1953) equations (6)-(8) for drag coefficient Cx = f(Re) of grain with different shape factor ψ = 1,0, 0,7 and 0,5 have been developed. Equations (6)-(8) are valid in transitional regime of falling 6 < Re < 1·103. Then fall velocities for sandy grains with diameter d = 0,25-2 mm and water temperaturę 10°C have been calculated using iteration procedure. Values of calculated fall velocity have been compared with results given front empirical fonnulas known from literature. It have been stated that the best results were obtained for sand grains average shape coefficient ψ = 0,7 when fall velocity was determined for grains diameter d= 0,25-1 mm from formulas of Zhang (18) and Budryk (9), for d = 1-2 mm from formulas of Gruat (17) and Gončarov (15) and for d = 0,25-2 mm from Zhang (18) formula.