Stone Processing Research Articles

Influence of Stone Processing Waste on Mechanical, Durability, and Ecological Performance of Hybrid Fiber-Reinforced Engineered Cementitious Composite

The current study is focused on the characteristics of sustainable engineered cementitious composites (ECCs) with the inclusion of various types of fibers (PVA, PET, and MSE) in hybridization, silica sand (SS), river sand (RS), and stone processing waste (SPW). SPW is termed as hazardous material because of the presence of finer particles and inorganic substances which contribute to leaching problems, and cause adverse effects on aquatic life and human health. The objective of this study was to introduce new kind of cost-effective, sustainable, and greener ECC to encourage its use in diversified applications. The characteristics of different ECC mixtures were assessed by observing the slump flow, compressive, tensile, flexural, ultrasonic pulse velocity, air permeability, electrical resistivity (ER), sorptivity, ecological behavior, and cost analysis. Experimental results revealed that the combination of micro-fibers enhanced the overall performance of ECC with reduction in the matrix cost. The addition of SPW in place of aggregates enhanced the flowability, strength, and durability characteristics, and contributed to reducing the carbon dioxide emissions. This study confirms that the combined use of PVA, PET, and MSE fibers with SPW inclusion is a promising alternative over the fully PVA blended ECC with SS.

Investigation of fragment separation during a circular saw blade cutting rock based on ANSYS/LS-DYNA

Circular saw blades are widely used in stone processing. The circular saw blade cutting hard rock numerical simulation model based on ANSYS/LS-DYNA was established to investigate the complex dynamic problem in rock cutting. The failure mechanism of the rock and the influence of cutting parameters on the cutting force and rock fragments were studied by numerical simulation. The results demonstrated that the failure modes of the rock were mainly tensile failure with some shear failure and compressive failure. The cutting force and the number of fragments increased with the feed speed. With the increasing circular saw blade rotational speed, the cutting force and the number of fragments decreased and tended to stabilize. With the distance between the circular saw blades increasing, the cutting force and rock fragments number increase and then maintain basic stability, and when the distance between double circular saw blades reaches 25 mm, it will form a completed rock plate and the interaction of circular saw blades will decrease. The numerical simulation can accurately simulate rock breakage and force when a circular saw blade cuts rock.

Red Ceramics Produced with Primary Processing Fine Waste of Ornamental Stones According to the Circular Economy Model

The ornamental stone industry is growing and has a large production in Brazil, mainly in Espírito Santo, where the largest production in the country is concentrated. Brazil is part of the group of countries that produce the most ornamental stones in the world; however, the generation of waste in this sector is very large. These ornamental stone wastes when used for the manufacture of new materials, such as red ceramics, contribute to the reduction in the raw material clay and to the reduction in the environmental impact. The objective of this work was to incorporate fine wastes from the processing of ornamental stones called FIBRO in red ceramics and later, to contribute to the standardization of the use of these wastes in the ceramic industry, contributing to the manufacture of more economical and sustainable products. Wastes were incorporated in the proportion of 0 to 50% by mass that were prepared by extrusion and fired at 900 °C, 950 °C, and 1000 °C. After firing, the physical and mechanical properties of the ceramic material were evaluated. Specific mass apparent, water absorption, porosity, and flexural strength by three points tests were carried out. The results showed that from 30% at the lowest temperature, tile is already fabricated within the values stipulated by the standards, thus saving energy. The analyzed waste is a material with excellent chemical characteristics to be used in the ceramic mass, in addition to having improved the technological properties of the material, such as less water absorption and greater flexural strength.

Quality of soil under deposits of dimension stone processing wastes

RESUMO O Brasil tem destaque mundial no setor de rochas ornamentais, e o Estado do Espírito Santo participa como o principal polo de beneficiamento do País. A transformação de blocos rochosos em chapas polidas gera grande quantidade de resíduos, que têm sido depositados diretamente sobre o solo. O conhecimento das características naturais do solo em locais onde há disposição de resíduos e em locais seguramente não afetados por eles é imprescindível para o adequado gerenciamento desses efluentes. O objetivo deste trabalho foi analisar a qualidade do solo e a presença de metais potencialmente tóxicos em três áreas de disposição no município de Cachoeiro de Itapemirim (ES). Os depósitos estão em posições topográficas distintas (topo, vertente e vale) e foram instalados em áreas com diferentes tipos de uso do solo. Além da comparação com amostras-testemunho, as áreas são comparadas entre si e alguns dados são confrontados com limites estabelecidos pela Resolução do Conselho Nacional do Meio Ambiente (CONAMA) 420/2009, bem como com a faixa considerada comum em solos do Espírito Santo. Há interação entre o resíduo e o solo, aumentando o pH, os teores de K e Na e os parâmetros soma de bases, capacidade de troca catiônica efetiva, capacidade de troca catiônica potencial e saturação por bases nos locais situados em encosta e alto topográfico. Com relação aos metais potencialmente tóxicos, não foi encontrado um padrão claro de ocorrência que vincule sua origem aos resíduos; ao contrário, teores mais elevados de metais na área que recebe esgoto sem tratamento indicam uma possível fonte externa de Cu, Cr, Pb, Zn e Ni.

Determining the rational operating parameters for granite crushing to obtain cubiform crushed stone

Purpose. Determining the rational operating parameters for granite crushing under impact in the field of centrifugal forces to obtain cubiform crushed stone. In order to achieve the purpose set, the task is to determine the operating parameters for obtaining the main grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. Methods. The crushing process of granite crushed stone is studied in the conditions of the Kolomoievskyi Granite Quarry, Dnipropetrovsk region. Granite crushed stone with an initial grain-size of 100.0-0.0 mm and strength grade of M1400 is subjected to crushing. The accelerating rotor rotation frequency is the design value n = 200-1200 min-1. Fine crushing of granite is performed in a centrifugal-impact crusher by a free impact in the field of centrifugal forces. Findings. The optimal speed modes of centrifugal crusher operation, which provide the production of high-quality crushed stone with a maximum content of 90-95% cubiform fractions, have been substantiated. Originality. The yield dependences have been obtained of the grain-size classes: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm depending on the speed mode of the centrifugal crusher operation. Practical implications. The operating parameters for obtaining the main grain-size classes of cubiform crushed stone from granite have been determined: -50.0 + 20.0; -40.0 + 20.0; -20.0 + 10.0; -10.0 + 5.0 and 5.0 mm. In particular, it has been determined that for the production of cubiform crushed stone with -50.0 + 20.0 mm grain-size, the rotor rotation reasonable speed is 400-500 min-1 (the speed of material departure from the accelerating rotor is 45-50 m/sec); for cubiform crushed stone of -40.0 + 20.0 mm grain-size, the speed mode is 200 min-1 (25 m/sec); for cubiform crushed stone of -20.0 + 10.0 mm grain-size – 600-650 min-1 (70-80 m/sec), respectively. The maximum content of cubiform fractions in the -20.0 + 10.0 mm grain-size class is 95%, which is achieved at a rotor speed of 650-700 min-1 (departure speed is 75-80 m/sec). The maximum content of cubiform fractions in the -10.0 mm grain-size class is 94-95%, which is achieved at the accelerating rotor speed within 700-800 min-1 (departure speed is 70-80 m/sec). The obtained data make it possible to practically choose a rational speed mode of the centri-fugal-impact crusher operation to obtain the maximum yield of cubiform crushed stone.

Thulium Fiber Laser's Dust for Stone Composition Analysis: Is It Enough? A Pilot Study.

Introduction: We aimed to evaluate if the biochemical composition of urinary stones can be determined by analyzing the stone dust only, and whether a photo taken during the surgery could be useful for completing the morpho-constitutional analysis. Materials and Methods: Twenty patients went through a retrograde intrarenal surgery for renal stone treatment with thulium fiber laser (Fiber Dust; Quanta, 2020) using 150 μm silica core laser fibers. After laser lithotripsy, residual fragments (RF) were removed with a basket (ZeroTip; Boston Scientific) and spontaneously floating stones particles were considered stone dust and were aspirated through the working channel. Pairs of RF and stone dust were labeled and sent to analysis by scanning electron microscopy and Fourier transform infrared spectroscopy. Photos of the stone (surface and section) were taken from videos recorded during the surgery. Results: A total of 20 patients were included in this study. Mean age was 49.8 years with metabolic and genetic disorders. Mean stone volume was 750 mm3 for ureteral stones and 2334 mm3 for renal stones. Mean stone density was 1187 HU. Positive urine culture was found in 25% patients. In 2/20 (10%), the biochemistry differed only in the relative proportions of each constituent, while in 5/20 (25%), only one component was missing. Laser crystalline conversion was found in 3/20 (15%). Whewellite and weddellite layers were found in photos, thus adding missing information from dust stone analysis. Conclusion: By analyzing aspirated dust through the ureteroscope's working channel with physical techniques, we can understand the lithogenic process of the urinary stone, without needing to analyze the stone fragment. Morphologic analysis, given by a proper stone picture, adds missing information in specific cases.

Investigation of the Relationship Between Texture Coefficient and Electrical Current Consumption of the Cutting Machine with Different Lubricants and Cooling Fluids

Texture coefficient is one of the most effective physical factors in evaluating the engineering characteristics of rocks in various projects, such as drilling, cutting and advanced rate of full-face drilling machines. Evaluation of electricity consumption by disc-cutting machines is critical for monitoring and reducing expenses in the stone processing industry. In this study, the relationship between the textural characteristics of the rocks and the amount of electrical current consumed by the cutting machine in cutting hard stones was evaluated. For this purpose, ten samples of hard rock were investigated. For each rock sample, a microscopic slice was prepared. Then, five digital images were taken using the microscope from each division, and the values of textural characteristics, including area, perimeter, largest diameter, and most minor diameter of all grains in each embodiment, were determined. Then, the texture coefficient of all studied stone samples was computed based on the determined specifications. Finally, the relationship between the texture coefficient and the rate of electrical current consumed by the cutting machine was investigated using statistical models. The results revealed that although the electric current used by the cutting machine decreased when the texture coefficient increased in some samples, no significant relationship between the texture coefficient and the amount of electric current used by the cutting machine was observed for hard stone samples. It was also found that the impact of lubricant type on the cutting machine performance is negligible.

Mechanical properties and interface improvement of bamboo cellulose nanofibers reinforced autoclaved aerated concrete

Autoclaved aerated concrete (AAC) has low density, suitable compressive strength, and excellent thermal and sound insulation capacity for building non-bearing walls. However, porous AAC blocks usually have low flexural strength and thus are prone to cracking during service life. Herein, bamboo cellulose nanofibers (BCNF) were incorporated into AAC matrix to enhance mechanical strengths. The BCNF was further modified by 3-mercaptopropyl-trimethoxysilane (KH590) to improve the interfacial bonding between BCNF and AAC matrix. Results showed that the AAC with the addition of 0.3 wt% KH590-modified BCNF had 49.2% and 20.7% higher flexural strength and compressive strength than those without BCNF, respectively. AAC slurry belongs to a pseudoplastic fluid with a yield value, which can be described by Bingham rheological model. With the increase of shear rate, the stress of AAC slurry increased and the viscosity decreased exponentially. The interfacial bonding of BCNF/AAC-matrix was characterized by FTIR, XPS, NMR, and SEM analyses. It was confirmed that the siloxane groups of KH590 react with the hydroxyl groups of BCNF, thus grafting the BCNF with hydrophobic moieties and improving their interfacial adhesion with AAC matrix. In addition, granite powders collected from stone processing mill were utilized as a main component of AAC matrix. This study provides a feasible way of utilizing renewable materials and solid waste in preparing high-performance AAC as green building materials.

Medieval Quarry Near the Koksa Bay (Krasnoyarsk Reservoir) as the Evidence of Possible Migration of the Yenisei Kyrgyz from the Sayan Mountains to the Middle Yenisei

Purpose. The results of archaeological survey in 2021 along the western shore of the Krasnoyarsk reservoir in the Koksa Bay area are presented in the process of field research. Previously unknown cultural and historical objects were revealed – a quarry on Mount Bol’shoi Togurtag, presumably of medieval times, and mounds in the form of rounded stone objects at the foot of the mountain 1 250 m from the Koksa bay.Results. The material extracted from the quarry was used in the construction of these mounds, located at the foot of the mountain. This assumption is evidenced by a similar type of rock in the quarry and on the mounds (they are of magmatic origin). Previously, similar objects for this territory were not mentioned in the scientific literature. Is the technological originality in stone processing techniques evidence of the migration to this territory of any mobile group of the population from the outside, where such technology was traditional? For example, medieval Kyrgyz kurgans in the Usinsk valley of the Western Sayan, where there are many rocks of igneous origin, are similar to them in their appearance and composition of the building material. Therefore, it is logical to assume that here, on the Middle Yenisei, some group of “Usintsy” migrated, which was quite likely as part of the process of returning to their homeland of the Yenisei Kyrgyz after the Great Power era. An exhaustive answer to this question can be given in the future only after an archaeological study of the rounded stone structures located here, similar to medieval “сhaatas” and “suukter” mounds, but composed, as indicated, of material of magmatic origin, unusual for this territory, in the form of large and medium-sized blocks of “torn” forms.Conclusion. The quarry on Bol’shoi Togurtag Mount demonstrates more labor-intensive process of obtaining stone material in comparison even with the extraction of “slabs” from layers of Devonian sandstone for the construction of mounds of the Tagar culture. All of the above and determines the originality of this object among those known in Khakassia. In this regard, their further study seems to be very relevant and expedient for the formation of a complete picture of the origin of medieval archaeological sites on the left bank of the Yenisei.

Business Strategy to Increase the Asset Value of Pt. Martheen House (Case Study: Land in Pattimura Airport, Ambon)

PT. Martheen House is the owner of the Idle Assets in North Maluku, Ambon. Numerous project options exist in the vicinity of Asset Idle, including the Pattimura international airport in Ambon, the processing of raw materials from crushed stone, and the surrounding countryside. In addition to numerous project options, Idle Assets also has office space and a total fisheries asset and facility value of Rp 7,761,500,000. In this study, PT. Martheen House intends to devise a plan to raise the selling price of its assets. Alternative projects that boost the resale value of these assets will be analyzed and profitable project ideas will be selected. utilizing SWOT to determine the internal components of an organization PESTLE to study competitors to explain external elements from the company that must be open, Porter’s Five Force to enable the company to overcome the underlying opportunities and dangers in the company’s external environment. After performing a Feasibility Study to establish the alternatives and the US Index to determine the chosen resource, the corporation must maximize capital in the form of Equity, Debt, or both to determine which resource to select. The final step is to determine the internal financial position using Financial Ratio Analysis.The investigation reveals that the chosen alternative project is the crushed stone processing project for Rp. 2.035 billion, the Warehouse Project + small office for Rp. 8.787 billion, and the Transit Hotel Project for Rp. Using loans to finance the implementation of this alternate project is doable. Due to the company’s internal financial predicament, it will implement the first alternative project selected, the crushed stone processing project.

Recycling of granite powder and waste marble produced from stone processing for the preparation of architectural glass–ceramic

• Glass-ceramic was prepared using granite powder and waste marble by melting-sintering method. • The addition of MgO changes the main crystalline phase of the glass–ceramic from wollastonite to augite. • The acid resistance of glass-ceramics is weakened with the increase of basic oxide content in the chemical composition. • The glass–ceramic with flexural strength of 146.95 MPa and Vickers hardness of 10.24 GPa can be achieved. A large amount of solid waste is generated during the stone processing, and a serious environmental issues has arisen from the accumulation of these wastes. In this work, granite powder and waste marble are used to prepare architectural glass–ceramic. The mechanical properties, microstructure, and acid resistance of glass-ceramics designed with different compositions were investigated. With the increase of waste marble content, the main crystalline phase of glass–ceramic changed from anorthite to wollastonite, and the flexural strength of glass–ceramic was also enhanced. When the mass ratio of granite powder to waste marble is 40:60, a CaO-Al 2 O 3 -SiO 2 (CAS) glass–ceramic with a flexural strength of 109.33 MPa and a Vickers hardness of 6.61 GPa is obtained. After the addition of MgO, the main crystalline phase of the glass–ceramic is augite. Under the addition of 5 wt% MgO, the flexural strength and Vickers hardness of CaO-MgO-Al 2 O 3 -SiO 2 (CMAS) glass–ceramic reached the maximum, which are 146.95 MPa and 10.24 GPa, respectively. The mechanical properties of these two types of glass-ceramics developed from granite powder and waste marble can meet the requirements of building materials. From the acid resistance test results, it was found that the higher the content of MgO and CaO in the chemical composition of glass–ceramic, the worse the acid resistance. Therefore, the basic oxide content should be carefully controlled in the composition design of glass–ceramic. This technology of converting granite powder and waste marble into value-added glass–ceramic provides a promising method for the utilization of solid waste from stone processing, which can greatly improve the sustainability of the stone industry.

Respiratory symptoms, spirometric, and radiological status of stone-cutting workers in Bangladesh: A cross-sectional study.

Background and AimsInhalation of respirable silica dust during several stone processing methods can result in several respiratory diseases. However, data are scarce regarding the respiratory health of stone‐cutting workers in Bangladesh. We aimed to determine the point prevalence of respiratory symptoms, lung function status and radiological abnormalities among the stone‐cutting workers.MethodsThis cross‐sectional study was conducted among 200 stone‐cutting workers. Adult workers having a job experience of at least 3 years participated in this study. Then inquiry was made regarding respiratory symptoms with the help of a preformed questionnaire. All the participants underwent chest X‐ray and spirometry. A respiratory dust sampler was used to measure the dust concentration of the stone‐cutting factories.ResultsAmong the 200 stone‐cutting workers, 89% (178) showed at least one chronic respiratory symptom while they had chest tightness (75.5%), chronic cough (74.5%), and shortness of breath (66.5%) as the most prominent ones. Spirometry findings revealed that the mean forced expiratory volume in 1 s (FEV1) value was 1.42± 0.65 L in the obstructive pattern, 1.43 ± 0.73 L in the restrictive pattern. The mean forced vital capacity (FVC) value was 2.53 ± 1.12 L in the obstructive pattern, 1.53 ± 0.75 L in the restrictive pattern. 42.69% of stone‐cutting workers who complained of at least one respiratory symptom had abnormal chest X‐ray findings. Those with progressive massive fibrosis had the lowest mean FEV1 value (0.75 ± 0.50 L). While measuring workplace dust concentration, we found high particulate matter (PM) 2.5 (979.78 µg/m3) and PM 10 (1298.35 µg/m3) values.ConclusionsMost of the stone‐cutting workers in our study exhibited different respiratory symptoms. These symptoms were associated with abnormal lung function and radiology. Further longitudinal studies are recommended to determine the actual dimension of this problem.

Sustainable precast concrete blocks incorporating recycled concrete aggregate, stone crusher, and silica dust

Due to rapid urbanization and onset of various infrastructure projects, construction and demolition waste management is a key challenge to related stakeholders. The utilization of stone crusher dust (SCD) and silica dust (SD) generated as wastes in stone processing units is also a matter of concern as it leads to air pollution. As per the published research articles, these industrial wastes can replace a significant proportion of natural aggregates in concrete, however, the authors could not find a study on utilization of coarse (4.75–10 mm) recycled concrete aggregates (RCA) in combination with SCD, and SD in making zero-slump concrete for producing M-40 grade paver blocks. This study evaluates the effect of incorporating (0%, 15%, 30%, 45%, 60%, 75%) coarse RCA. Then, the feasibility of incorporating (0%, 20%, 40%, 60%, 80%, 100%) SCD, and SD with optimum coarse RCA was investigated. The workability, fresh density, compressive strength, flexural strength, split tensile strength, dynamic modulus, water absorption, void ratio, abrasion resistance, and sulphate and acid resistance properties of paver blocks were evaluated. As per the results, the workability increased 2.6% at 45% coarse RCA, however, it decreased 4.6% and 10.2% at 100% SD and 100% SCD, respectively. The compressive strength decreased 6% at 45% coarse RCA, whereas it increased 2.8% and 3.8% at 100% SD and 100% SCD. Microstructure analysis (TGA, FT-IR, SEM) was performed to observe the changes in mass loss, chemical properties, pore analysis, shape, and texture of aggregates. Based on the observations, coarse RCA can replace up to 45% natural aggregates, whereas SD, and SCD can replace even 100% river sand without having significant impact on the properties. The environmental and economic assessment of 1 m3 of selected concrete mixes were also performed. The incorporation of 45% coarse RCA reduced 1% GWP and 3% primary energy consumption. The use of 100% SD with 45% coarse RCA can reduce 4.8% GWP and 11.8% primary energy consumption, whereas 100% SCD with 45% coarse RCA can reduce 5% GWP and 12% primary energy consumption. The production cost of 1 m3 control mix increased 24% at 45% coarse RCA , whereas it increased 5% and decreased 3% at 100% SD, and SCD, respectively. So, utilization of coarse RCA, SD, and SCD can save significant number of natural resources and pave the way to sustainable development by converting these industrial wastes into resources.

Evaluation of use of marble and granite cutting waste to the production of self-compacting concrete

Due to the continuous storage of large quantities of marble and granite waste (MGW), generated during the processing of ornamental stones, researchers have been using this material in a sustainable way to reduce its adverse impacts on the ecosystem. In this study, the main objective was to evaluate the effect of using MGW on mechanical properties and durability of self-compacting concretes (SCC), as part of the fines required to ensure self-compacting characteristics. Also, it was investigated this material as a new possibility in the composition of a ternary cement modality. For this, an experimental program was developed with four SCC mixtures, in which tests were performed to determine the properties in the fresh state, hardened properties, durability, and microstructural analyses. The test results indicated that all mixtures complied the self-compacting requirements and the incorporation of MGW contributed to the stabilization of the concretes. The mixture with CPV-ARI cement and MGW incorporated as fine in the concrete, and the mixture with MGW both incorporated as fines in the concrete and in the composition of ternary cement CP-MMG did not present statistically significant differences for some results of the mechanical properties. Besides, these mixtures provided improvements and similar results of some durability and microstructural tests, respectively. In general, the different possibilities of utilization of the residue proposed in this study, generate an appropriate destination for MGW and propose a viable alternative for the reduction of clinker consumption in cement production.

The preparation of paddy soil amendment using granite and marble waste: Performance and mechanisms

The wastes generated from the mining and processing of granite and marble stone are generally regarded as useless. However, these waste materials were used as the soil amendments for the first time. The functional groups, crystalline structure and micro-morphology of granite and marble wastes amendments (GMWA) were different from the original wastes demonstrated by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR) and Scanning electron microscope-energy dispersive spectrometer (SEM-EDS) analyses. With the addition of the amendments, the cation exchange capacity, electrical conductivity and nutrient availability of the soil increased, and the extractable heavy metals of the soil reduced significantly. Under the condition of the addition of 3% amendments, 7.0%, 99.9%, 99.7% and 70.5% of Cu, Pb, Zn and Cd in exchangeable fractions in soil were transformed to the more stable Fe-Mn oxides- or carbonates-bounded fractions. Tessier method and correlation analysis showed that the reduction of extractable metals in the acidic paddy soil can be attributed to the adsorption of available SiO2, the co-precipitation induced by the elevated pH value, the complexation induced by Fe-Mn oxides and the cation exchange induced by mineral nutrients. This study provides a new strategy for resource recovery of waste stones and remediation of heavy metal-contaminated soil.

Assessment of Limestone Waste Addition for Fired Clay Bricks.

Our aim was to investigate the feasibility of using limestone waste resulting from stone processing for the manufacturing of fired clay bricks. Waste materials were considered as a partial replacement for clays to reduce the exploitation of natural resources and as a response to the climate neutrality commitments. The samples were prepared to have a waste content of up to 15% and were fired at a temperature of 900 °C. The chemical and mineralogical composition and the physical analysis of raw materials were investigated by using SEM–EDS and XRD diffraction. The result showed an increase in CaO in the clay mixture due to the presence of limestone, which reduced the shrinkage of the products’ compressive strength, up to 55% for samples with a higher content of limestone (15 wt.%), and influenced the samples’ color by making them lighter than the reference sample.

Phase Formation and Physical and Mechanical Properties of Fe‒Cu–Ni‒Sn–VN Composites Sintered by Vacuum Hot Pressing for the Diamond Stone Processing Tools

Phase Formation and Physical and Mechanical Properties of Fe‒Cu–Ni‒Sn–VN Composites Sintered by Vacuum Hot Pressing for the Diamond Stone Processing Tools

New observations on Urartian quarrying in Lake Van Basin

Urartian architectural remains in eastern Turkey, Armenia, and north-western Iran bear witness to intensive quarrying during this period. Building materials at royal centres reveal that Urartians used local resources from the immediate vicinity of settlements, but they also carried out intensive quarrying at distant locations. Extraction, transportation, and processing of stone are labour-intensive activities which require a significant workforce. For these challenging undertakings, Urartians employed an effective administration of labour and advanced metal technology. The Urartian Kingdom marks an interesting starting point for quarrying in ancient Anatolia and the Near East in the 1st millennium BC. Sardurburç Building inscriptions at the north-western tip of Van Kalesi bear the first textual evidence for the name of a quarry, the city of Alniunu. Additionally, traces of quarrying near major settlements like Van Kalesi, Zivistan, Lower Anzaf, Upper Anzaf, Aznavurtepe, Ayanis, Çavuştepe, Körzüt, and Keçikıran in Lake Van Basin, and important water systems like the Minua Canal provide new information about stages of quarrying. Thin-section analysis of stone blocks sampled from Urartian centres allow us to determine the petrographic properties of building materials. Thin-section analyses reveal that sedimentary rocks (limestone, travertine, sandstone) and igneous rocks (gabbro, basalt, andesite) were used at Urartian centres.

Ornamental Stone Processing Waste Incorporated in the Production of Mortars: Technological Influence and Environmental Performance Analysis

The technological performance and environmental advantages of replacing sand by ornamental stone processing waste (OSPW) in the production of mortars for civil construction were studied. Technological properties associated with the standard consistency index, squeeze flow and bulk densities as well as the determination of water retention and calorimetry analysis were evaluated in the mortars’ fresh state, whereas capillarity tests as well as mechanical resistance by flexural and compression tests were determined in the hardened state for mortars incorporated with 10, 30 and 60 wt.% of OSPW substituting sand. Three different types of Portland Cements were considered in the incorporated mortars production. For these mortars environmental analysis, their corresponding life cycle assessment results were compared to that of conventional waste-free (0% OSPW) control mortar. It was found that the OPSW incorporation acts as nucleation sites favoring a hydration process, which culminates after 28 days of curing in the formation of more stable phases identified as hydrated calcium silicates by X-ray diffraction (XRD) amorphous halo. It was also revealed that both flexural and compression improved resistance for the incorporated mortars after 28 curing days. In particular, the calorimetry and XRD results explained the better mechanical resistance (12 MPa) of the 30 wt.% OSPW incorporated mortar, hardened with Portland Cement V, compared not only to the control, but also to the other incorporated mortars. As for the environmental analysis, the replacement of sand by OSPW contributed to the reduction in associated impacts in the categories of land use (−5%); freshwater eutrophication (−9%); marine eutrophication (−6%) and global warming (−5%).

The study on flexible manufacturing system in building decoration stone processing

Abstract Stone materials are widely used in interior and exterior decoration design and public facilities construction. They are one of the essential materials in the construction and decoration field. With the increase in demand of the personality and quality of the decoration materials, intelligent manufacturing of stone processing must be required. With the development of manufacturing technology, especially the rapid development of automatic control technology, CNC machining technology and industrial robot technology, flexible manufacturing technology (FMI) have been used. In the paper an intelligent flexible processing system of stone is designed, which is composed with CNC processing tool, material transmission and storage system, computer control system and stone processing process monitoring system. It can realize fully automatic and intelligent flexible production from building stone processing, stone handling, comprehensive waste treatment, tool optimization and computer control. The calculation method of optimal equipment layout is explained and the field layout of each unit of FMS is given. The purpose of this project is to improve the intelligent level of building decoration stone processing through flexible manufacturing technology and increase production efficiency and material utilization as well as to satisfy needs of diversified product.