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Number of results: 72
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Abstract

Concrete is generally produced using materials such as crushed stone and river sand to the extent of about 80‒90% combined with cement and water. These materials are quarried from natural sources. Their depletion will cause strain on the environment. To prevent this, bottom ash produced at thermal power plants by burning of coal has been utilized in this investigation into making concrete. The experimental investigation presents the development of concrete containing lignite coal bottom ash as fine aggregate in various percentages of 25, 50, and 100. Compressive, split tensile, and flexural strength as part of mechanical properties; acid, sulphate attack, and sustainability under elevated temperature as part of durability properties, were determined. These properties were compared with that of normal concrete. It was concluded from this investigation that bottom ash to an extent of 25% can be substituted in place of river sand in the production of concrete.

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Authors and Affiliations

T.S. Thandavamoorthy
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Abstract

This article presents the results of the study of changes in mineral and chemical composition of artificial aggregates consisting of coal shale (a hard coal mining waste) and fluidized ashes. Such an aggregate was used for road construction. After completion of the construction works but before making the road available for public use, significant deformation of the surface in the form of irregular buckling of the asphalt layer occurred. It was excluded that this resulted from mining damage, design errors or performance mistakes, among others. A study of the materials that had been incorporated in the construction layers was undertaken in order to find the component and the mechanism responsible for the buckling of the road surface. A comparison of the mineral and chemical composition of aggregate samples collected from the embankment where the road buckled with the reference sample and samples from places without deformations showed that the bumps in the road embankment consisted of minerals that were not initially present in the aggregate. Wastes produced as a result of high temperatures (slag and power plants ashes, metallurgical wastes) are not as stable in terms of chemical and phase composition in the hypergenic environment. As a result of the processes occurring in the road embankment, anhydrite, which is the primary component of fluidized ashes, was transformed into gypsum and ettringite. As a result of contact with water CaO (present in fluidized ashes) easily changed into calcium hydroxide. As the crystallization of these minerals is expansive, it resulted in the filling of pores and, in extreme cases, in a substantial increase in the volume of the aggregate and, consequently, in the deformation of the road surface.
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Authors and Affiliations

Zdzisław Adamczyk
Marcin Grygierek
Marian Łupieżowiec
Jacek Nowak
Ewa Strzałkowska
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Abstract

In this paper, the influence of biomodification of recycled concrete aggregate (RCA) on some properties of concrete was studied. Sporosarcina pasteurii strain was chosen for biodeposition process. The RCA came from parent concretes with varying w/c ratio. Recycled aggregate concrete (RAC) with two levels of w/c ratio, made from RCA not subjected to biomodification, was treated as reference. Compressive strength, water absorption and sorption of concretes were tested. The most significant influence of the aggregate biomodification was found in the case of sorption and this effect was highest for RAC made from the aggregate yielding from better quality parent concrete.

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Authors and Affiliations

A.M. Grabiec
D. Zawal
J. Starzyk
D. Krupa-Palacz
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Abstract

In the design of asphalt mixtures for paving, the choice of components has a remarkable importance,as requirements of quality and durability must be assured in use, guaranteeing adequate standardsof safety and comfort.

In this paper, an approach of analysis on the aggregate materials using fractal geometry is proposed. Following an analytical and an experimental approach, it was possible to find a correlation betweencharacteristics of the asphalt concrete (specific gravity and porosity) and the fractal dimension ofthe aggregate mixtures.

The studies revealed that this approach allows to draw the optimal fractal dimension and, conse-quently, it can be used to choose an appropriate aggregate gradation for the specific application;once the appropriate initial physical parameters are finalized.

This fractal approach could be employed for predicting the porosity of mixed asphalt concretes,given as input the fractal characteristics of the aggregate mixtures of the concrete materials.

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Authors and Affiliations

G. Leonardi
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Abstract

Alkali-aggregate reactivity (AAR) is one of the major causes of damage in concrete. Potential susceptibility of aggregates to this reaction can be determined using several methods. This study compares gravel alkali reactivity results obtained from different tests conducted on coarse aggregates with complex petrography. The potential for the reactivity in the aggregates was revealed in the chemical test using treatment with sodium hydroxide. Optical microscopy, scanning electron microscopy and X-ray diffraction were used to identify the reactive constituents. The expansion measured in the mortar bars test confirmed that the aggregate was potentially capable of alkali silica reactivity with consequent deleterious effect on concrete.

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Authors and Affiliations

Z. Owsiak
P. Czapik
J. Zapała-Sławeta
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Abstract

This paper presents application of optical microscope for evaluation of microtexture changes of coarse aggregate during simulated polishing in laboratory. Observations of the apparent changes on surfaces of seven different aggregates are presented. Simulation polishing of aggregate was performed in accordance with PN-EN 1097-8:2009. lmages of the aggregate surface were taken with the optical microscope in the reflection mode in particular stages of polishing. Digital images were analyzed. Standard deviation was determined on the basis of the histogram of intensities from digital images of the surfaces of aggregate grains which was assurned as the measure of changes in microtexture during simulated polishing (namely the σh parameter). Statistical analysis has shown that the changes of the σh parameter between the particular stages of polishing confirm certain trends related to the petrographic characteristic of the rocks. Aggregates which included minerals of similar hardness (granodiorite, dolomile, basalt) were more prone to polishing than gabbro and postglacial. Regeneration of the microtexture, the recovery to its original asperity, occurred in the case of quartz sandstone and steelmaking slag.

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Authors and Affiliations

W. Gardziejczyk
M. Wasilewska
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Abstract

Recycling construction and demolition waste not only reduces project costs; and saves natural resources, but also solves the environmental threat caused by construction waste disposal. In this paper, C25 waste road concrete is used as an experimental material, the uniaxial compression strength and tensile splitting strength of C25 RAC whose coarse aggregate replacement rate is 0%, 25%, 50%, 75%, and 100% are tested under the condition that the water-to-cement ratio is 0.47, 0.55 and 0.61. The results show: (1) the uniaxial compression strength and tensile splitting strength decrease with the increase of RAC; (2) for concrete with the same water-to-cement ratio, when the coarse aggregate replacement rate changes from 0% to 50%, the uniaxial compression strength and tensile splitting strength of RAC changes slightly. When the coarse aggregate replacement rate changes from 50% to 100%, the uniaxial compression strength and tensile splitting strength of RAC decreases rapidly

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Authors and Affiliations

X.H. Deng
Z.L. Lu
P. Li
T. Xu
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Abstract

The mechanical characteristics of the railway superstructure are related to the properties of the ballast, and especially to the particle size distribution of its grains. Under the constant stress-strain of carriages, the ballast can deteriorate over time, and consequently it should properly be monitored for safety reasons. The equipment which currently monitors the railway superstructure (like the Italian diagnostic train Archimede) do not make any “quantitative” evaluation of the ballast. The aim of this paper is therefore to propose a new methodology for extracting railway ballast particle size distribution by means of the image processing technique. The procedure has been tested on a regularly operating Italian railway line and the results have been compared with those obtained from laboratory experiments, thus assessing how effective is the methodology which could potentially be implemented also in diagnostic trains in the near future.

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Authors and Affiliations

M. Guerrieri
G. Parla
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Abstract

The aggregate applied for the wearing course has a significant influence on skid resistance of road surfaces. However, it is difficult to evaluate the behaviour of road surface in use on the basis of the Polished Stone Value (PSV) determined for the aggregate according to the so called ‘British method’. The British method, which is currently used in many countries, does not allow to determine the influence of neither the grain size of the aggregate nor the type of the wearing course on skid resistance of road surface. The present paper suggests a method for evaluation of the British Pendulum Number (BPN) for road surfaces in laboratory conditions. The authors assumed the BPN for polished slabs, made from asphalt mixtures, as the criterion. The index was measured with the British Pendulum Tester. The simulation of the process was conducted on research stand (called slab polisher) built at Bialystok University of Technology (BUT). The results of laboratory tests indicate that surfaces from asphalt concrete (AC) have slightly higher values of BPN in comparison with the values determined for surfaces made from stone mastic asphalt (SMA).

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Authors and Affiliations

W. Gardziejczyk
M. Wasilewska
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Abstract

This paper presents numerical two-dimensional results for fine-grained concrete under quasi-static three-point bending at meso-scale. Concrete was modelled as a random heterogeneous three-phase material. The simulations for notched concrete beams were carried out with the standard finite element method using an isotropic damage constitutive model enhanced by a characteristic length of micro-structure by means of a non-local theory. The effect of the volume fraction, shape, size, statistical distribution and stiffness of aggregate was analysed. Moreover, the effect of the bond thickness, notch size and characteristic length of micro-structure on the material behaviour was numerically investigated. The FE results were compared with own laboratory test results and other meso-scale calculations for three-phase concrete elements.

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Authors and Affiliations

Ł. Skarżyński
J. Tejchman
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Abstract

A three Dimensional finite element model (FEM) incorporating the anisotropic properties and temperature profile of hot mix asphalt (HMA) pavement was developed to predict the structural responses of HMA pavement subject to heavy loads typically encountered in the field. In this study, ABAQUS was adopted to model the stress and strain relationships within the pavement structure. The results of the model were verified using data collected from the Korean Highway Corporation Test Road (KHCTR). The results demonstrated that both the base course and surface course layers follow the anisotropic behavior and the incorporation of the temperature profile throughout the pavement has a substantial effect on the pavement response predictions that impact pavement design. The results also showed that the anisotropy level of HMA and base material can be reduced to as low as 80% and 15% as a result of repeated loading, respectively.

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Authors and Affiliations

Joonho Choi
Youngguk Seo
Sung-Hee Kim
Samuel Beadles
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Abstract

Taking into account the numerous previous attempts to use waste glass for concrete production, an approach was proposed based solely on car side window glass waste. Only side window waste emerging during the production of car side windows was used during the research program. In this way, all key properties of the waste glass were under control (purity, granulometric properties, etc.). Two types of concretes with crushed side window glass, playing the role of coarse aggregate, were created. Concretes were differentiated by the amount of added crushed side window glass, which replaced 10–50% of the natural aggregate. Created concretes were thoroughly tested in the state of both a fresh mix and hardened composite. Consistency and air content of fresh mixes were tested. Slump was ranging from 15 mm to 20 mm and air content was ranging from 2.5% to 3.1%. Hardened composites were used to test apparent density, compressive strength, water absorption, water-tightness and resistance to freeze–thaw cycles. It was proven that concrete with side window glass as partial aggregate substitution is characterized by satisfactory mechanical properties (compressive strength after 28 days of curing was ranging from 51.9 MPa to 54.7 MPa), enabling its application as ordinary structural concrete. Properties of both fresh concrete mixes and hardened concretes based on crushed side window glass are similar to a reference concrete. It was proved that it is possible to replace up to 50% of natural coarse aggregate by crushed side window glass. Possible applications of the concretes in question were proposed. Experience gained during the research program is likely to be useful for tests of using crushed side window glass sourced from decommissioned cars and trucks. Areas where future research is needed are indicated.
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Authors and Affiliations

Bogdan Langier
1
ORCID: ORCID
Jacek Katzer
2
ORCID: ORCID
Maciej Major
1
ORCID: ORCID
Jacek Halbiniak
1
ORCID: ORCID
Izabela Major
1
ORCID: ORCID

  1. Częstochowa University of Technology, Faculty of Civil Engineering, ul. Dąbrowskiego 69, 42-201 Częstochowa, Poland
  2. University ofWarmia and Mazury in Olsztyn, Faculty of Geoengineering, ul. Oczapowskiego 2,10-719 Olsztyn, Poland
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Abstract

This paper investigates the behaviour of axially-loaded tubular columns filled with M20 grade concrete and partially replaced concrete. The parameters varying in the study are slenderness ratio (13.27, 16.58 & 19.9), and normal M20 grade concrete, partially replaced quarry dust and concrete debris. The effects of the various concrete mixes and composite action between the steel tube and the concrete core are studied and a graph visualizing the differences between the load carrying capacity and the axial deflection is plotted. Some of the performance indices like the Ductility Index (DI), Concrete Contribution Ratio (CCR), Confinement Index (θ) and Strength Index (SI) are also evaluated and compared amongst the CFST columns. From the results it has been noted that an increase in the L/D ratio decrease the behaviour of the composite columns irrespective of the in filled materials. The composite action was achieved in the CFST columns filled with partially replaced quarry dust and concrete debris when compared with hollow steel columns. The load carrying capacity of the CFST column increases by 32 % compared with the hollow tubular columns.

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Authors and Affiliations

P. Sangeetha
R. Senthil
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Abstract

The currently applicable legal provisions and also the economic concepts emphasize the importance of circular economy. In this aspect, it is very important to reduce the waste production respectively planning and running a business. Technical research is the key to finding a new applications for waste, in particular disposed on landfilling. Mining and energy industries belong to the biggest producers of waste in Poland. The total share of these two branches in waste production is up to 70% (mining and quarrying 53%; electricity, gas, steam and air conditioning supplay 17%). In environment, economy and social aspect, it is very important to develop this waste. The paper presents research on the physico-mechanical properties of the aggregates based on colliery shale supplemented by fly ash (20% - 40% supplement of fly ash). The following tests should be mentioned among performed: particle size distribution, the sand equivalent test, freeze resistance and direct shear tests. Also the chemical properties found in the literature was invoked. The research shows good physico-mechanical properties of the mixes, such as cohesion (44.62 kPa - 68.57 kPa) or internal firiction angle (34.74° - 40.52°). Though low resistance to weathering and a large susceptibility to frost heave (the mass loss after the freezing cycles is 76%) may limit its applicatin in road engineering. The sand equivalent tests were made only for aggregates. Tested materials shows usefulness for earthen structures. However, the research should be supplemented by chemical tests and also observations of the material properties changes as the effect of time. The research on the leachability of chemical pollutants, which will determine the acceptable share of ash in the mix, could be especially significant. The fact that fly ash contains a lot of sulphates and chlorides, which leach into the environment may pose a threat to living organisms.

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Authors and Affiliations

Mateusz Blajer
Agnieszka Stopkowicz
Justyna Adamczyk
Marek Cała
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Abstract

In the following paper, geovisualisation will be applied to one spatial phenomenon and understood as a process of creating complementary visualisations: static two-dimensional, surface three-dimensional, and interactive. The central challenge that the researchers faced was to find a method of presenting the phenomenon in a multi- faceted way. The main objective of the four-stage study was to show the capacity of the contemporary software for presenting geographical space from various perspectives while maintaining the standards of cartographic presentation and making sure that the form remains attractive for the user. The correctness, effectiveness, and usefulness of the proposed approach was analysed on the basis of a geovisualisation of natural aggregate extraction in the Gniezno district in the years 2005–2015. For each of the three visualisations, the researchers planned a different range of information, different forms of graphic and cartographic presentation, different use and function, but as far as possible the same accessible databases and the same free technologies. On the basis of the final publication, the researchers pointed out the advantages of the proposed work flow and the correctness of the detailed flowchart.
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Authors and Affiliations

Tymoteusz Horbiński
Beata Medyńska-Gulij
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Abstract

Geographical Information Systems have become essential tools for land analysis and the subsequent decision making in many fields of human activity. In the field of mining, GIS applications have appeared in ore deposit modelling, environmental pollution, or planning of mining spaces. In this research, the powerful multicriteria tools of GIS platforms have been applied for the determination of an index that has been called “Exploitability Index”. This index allows analyzing a series of outcrops of industrial aggregates, to help in the selection of the most adequate one to be enhanced from a mining approach. The multicriteria analysis has been applied for its determination, and as a result of this research, a model is proposed. The main criteria that condition the decision have been established in this model, along with their subsequent hierarchization and their weighting. The proposed model is applied to a specific case: the analysis of a series of outcrops of industrial aggregates (ophites) in Cantabria, Spain. After defining the Exploitability Index for those ophitic outcrops, it has been observed that the only deposit that has been classified as very suitable for its exploitation is the only one that has been really exploited, supporting the proposed methodology.

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Authors and Affiliations

Gema Fernández-Maroto
Julio Manuel de Luis-Ruiz
Raúl Pereda-García
Beatriz Malagón-Picón
Rubén Pérez-Álvarez
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Abstract

Road construction has been an ongoing engineering practice throughout human history. Although road construction technologies have changed over time, the raw material used has not changed for centuries, and it seems that it will not change in the upcoming centuries. Although some standards are used to determine the aggregate quality in road construction works, it is often complex and laborious to identify the aggregates that best meet the standards. Long-lasting and high-quality roads can be built and the most suitable aggregate is selected for the road. This study aims to select the most suitable aggregates used in hot-mix asphalt pavement production for road construction. In this study, multi-criteria decision-making methods were used for the selection of the aggregate that provides the best conditions. Aggregates used in constructing roads within the provincial borders of Ankara are produced from six stone quarries. To rank these aggregates and determine the ideal quarry for hot-mix asphalt production, the analytical hierarchy process (AHP) and the technique for order preference by similarity to an ideal solution (TOPSIS) method, which are multi-criteria decision making (MCDM) methods, were used. The results obtained from the tests on aggregates and hot-mix asphalts (HMA) were compared with the the best results based on the maximum and minimum limits determined in the standards. By comparing the the best results of the standards with the test results of the aggregates, weight scores were made for each test. Weight scores were scored and classified using the AHP and TOPSIS multi-criteria decision-making methods. As a result, the aggregate with the highest score and the quarry area represented by the aggregate were determined as the most suitable for hot-mix asphalt construction.
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Authors and Affiliations

Niyazi Bilim
1
ORCID: ORCID
Hamza Güneş
2

  1. Konya Technical University, Turkey
  2. Ankara Metropolitan Municipality, Turkey
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Abstract

This paper presents the results of research on the admixture of other rock fragments in the granodiorite aggregate (two types of hornfels) produced in Łażany II quarry. It discusses the impact of these components on the selected chemical and mechanical properties important for the use of the aggregate in road construction. Analysed granodiorite grit is a high-class construction material suitable for bituminous mixtures. Its quality is verified in accordance with the PN-EN 13043 standard. The admixture of hornfels in aggregate composition is a consequence of the natural occuring this rock in the Łażany II granodiorite deposit in the Strzegom-Sobótka massif. As there is not selective exploitation of the deposit an extracted raw material is not separated during processing As a result, the aggregate, composed predominantly of granodiorite, comprises variable admixture of hornfels. Tests of properties, such as water absorption, resistance to freezing, resistance to fragmentation, crushing strength, carried out on grain populations of various petrographic types separated from the general samples, exhibit that the presence of hornfels in the aggregate has a beneficial effect, particularly on the mechanical parameters of the produced aggregate. Moreover, two varieties of hornfels differ in terms of some chemical properties (affinity with bitumen, presence of sulphides). These features may affect the durability of the aggregate in the wearing course which is directly influenced by the exterior conditions typical for road pavements.
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Authors and Affiliations

Bartłomiej Grzesik
1
ORCID: ORCID

  1. Silesian University of Technology, Gliwice, Poland
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Abstract

Proper values of physical and mechanical properties and their homogeneity are one of major requirements deciding about technological suitability of the rocks quarried to manufacturing aggregates. These properties depend on the natural features of a rock, its mineral composition, texture and structure. The characteristic of aggregates and the technical requirements they must meet are normalized in adequate standards that describe the procedures of conducting particular determinations and the methods of interpreting their results. In the basaltoids (usually called basalts) of selected deposits of Lower Silesia that represent different intrusive forms, five textural varieties have been distinguished: aphanitic, aphanitic-porphyritic, porphyritic-aphanitic, porphyritic-nodular and nodular-porphyritic. The petrography and essential physical and mechanical properties of these varieties have been described in Tables 1 and 2, respectively. The highest technical parameters have the aphanitic and aphanitic-porphyritic rock varieties. They result mainly from the textures of these rocks and their insignificant weathering, and to a lesser degree from their mineral composition. The resistance to wear (micro-Deval) and the resistance to fragmentation (Los Angeles) of the aggregates that represent the grain fraction 10-14 mm of the five varieties of basaltoids and the rock composites were determined according to the standards PN-EN 12620: 2008 and PN-EN 13043: 2004. Of the aggregates produced from the five major varieties, only those made of the nodular-porphyritic basaltoids have the properties of lower categories, whereas the remaining four are the materials of very high quality. Additionally, it has been shown that by combining various basaltoid types it is possible to produce composite aggregates with the variable qualities belonging to the categories LA and MDE (Tab. 3). The effect of rock petrography on the differentiation of the parameters of aggregates depending on the grain fraction of the products (Fig. 1, Tab. 4) is the lowest in the case of the aggregates produced from the homogenous and not weathered rock. In contrast, the range of variability of the parameters is higher if the starting material to produce aggregates is composed of several textural varieties and shows signs of weathering as well. The possibility of delineation of the areas occupied in the deposit by basaltoids with specific textural varieties creates the conditions of determining the rock zones, from which the aggregates of the predicted quality may be produced. This quality may be controlled and partly changed to the user needs by producing aggregates from the specially prepared rock mixtures (i.e. the charge to crushers) with specified proportions of the basaltoid varieties.

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Authors and Affiliations

Marek Rembiś
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Abstract

This paper presents results of mineralogical and chemical research connected with the polymorphic transformations of dicalcium silicates in aggregate based on open-hearth slag and also slags from the current production of EAF (electric arc furnaces), and LF (ladle furnaces). Particular attention was paid to the transformation of the polymorph β-Ca2[SiO4] into the variant γ-Ca2[SiO4], which is undesirable from the perspective of using steel slags in road construction. A full mineralogical characterization of the tested metallurgical slags enabled the verification of the effectiveness of detecting the decomposition of dicalcium silicate in observations in UV light in line with the PN-EN 1744- 1+A1:2013-05 standard. On the basis of the conducted research, it was found that in the aggregate based on open-hearth slags and in the EAF furnace slag, dicalcium silicates are mainly represented by the β-Ca2[SiO4] polymorph, accompanied by α’-Ca2[SiO4]. The slag from the LF furnace was characterized by a different composition, with a strong advantage (57%) of the α’-Ca2[SiO4] variety, with a 1% share of the β-Ca2[SiO4] and 15% of the γ-Ca2[SiO4].
It was found that the transformation of β-Ca2[SiO4] into γ-Ca2[SiO4] can take place only under certain conditions in the metallurgical process, but the process is not influenced by hyperergenic factors, as evidenced by the fact that after more than 100 years of storage of open-hearth slag, on the basis of which the aggregate was produced, it was primarily marked with all the variants of β-Ca2[SiO4], without the polymorph γ-Ca2[SiO4].
The comprehensive characterization of the slag phase composition requires use of an appropriately selected research methodology; this is of key importance prior to the secondary use of this material, especially in the presence of the γ-Ca2[SiO4] polymorph. It has been determined that the most accurate test results are obtained using the XRD technique. The method of determining the decomposition of dicalcium silicate according to the PN-EN 1744-1+A1:2013-05 standard proved to be unreliable. It seems that in the situation of using LF slag as an artificial aggregate, taking the test results according to the method described in the PN-EN 1744-1+A1:2013-05 standard as being decisive is very risky, especially on a large scale (e.g. in communication construction).
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Authors and Affiliations

Iwona Jonczy
1
ORCID: ORCID
Bartłomiej Grzesik
2
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Mining, Safety Engineering and Industrial Automation, Gliwice, Poland
  2. Silesian University of Technology, Faculty of Civil Engineering, Gliwice, Poland
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Abstract

In this paper, a new set of intuitionistic fuzzy aggregation operators have been introduced under the environment of intuitionistic fuzzy sets (IFSs). For this, firstly focused on some existing aggregation operators and then new operational rules known as Dombi operation have been pro- posed which make the advancement of flexibility behavior with the parameter. Based on Dombi operation laws, some new averaging and geometric aggregation operators namely, intuitionistic fuzzy Dombi weighted averaging, ordered weighted averaging and hybrid weighted averaging operator, classified as IFDWA, IFDOWA and IFDHWA operators respectively and intuitionistic fuzzy Dombi geometric, ordered weighted geometric and hybrid weighted geometric operators, labeled as IFDWG, IFDOWG and IFDHWG operators respectively have been proposed. Further, some properties such as idempotency, boundedness, monotonicity and commutative are investigated. Finally, a multi-attribute decision-making model has been developed for the proposed operators to select the best mutual fund for investment. The execution of the comparative study has been examined with the existing operators in this environment.

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Authors and Affiliations

Chiranjibe Jane
Madhumangal Pal
Guiwu Wei
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Abstract

Arid areas are particularly susceptible to soil erosion due to long dry periods and sudden heavy downpours. This study investigates the aggregate size distribution and aggregate stability of twelve tilled fallow areas of Hyderabad district, Sindh, Pakistan. This study determined aggregate size distribution by dry sieving to evaluate the seedbed condition and aggregate stability using wet sieving to assess the susceptibility of tilled fallow areas to soil erosion. The aggregate size distribution of the soils of the selected areas was highly variable. Gulistan-e-Sarmast had the largest number of clods (51.0%) followed by Kohsar (49.0%), Latifabad # 10 (41.10%) and Daman-e-Kohsar (39.0%). Fazal Sun City, the left side of the Indus River, the Village Nooral Detha and the left side of the Abdullah Sports city had a greater number of large (>8.0 mm) and small aggregates (<0.5 mm). The optimum aggregate size distribution was found in the left side of the channel, which had the largest number of aggregates (50.50%) in the 0.5–8.0 mm sieve size range. Maximum aggregate stability (AS) was found in Gulistan-e-Sarmast (46%), Kohsar (42%) and Latifabad # 10 (34%), while all other soils had minimum aggregate stability (<14%). The minimum aggregate stabilities demonstrate that the tilled fallow areas of Hyderabad district are highly susceptible to erosion. Therefore, the present study suggests investigating potential ways to enhance the aggregate stabilities of soils.

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Authors and Affiliations

Ahmed Tagar
Jan Adamowski

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