Characteristics of Waste Generated in Dimension Stone Processing

Natural dimension stone processing generates large volumes of stone waste, which have a significant impact on the environment, as well as on the efficiency and profitability of the stone-processing plant. The article presents the characteristics of waste produced as a result of natural dimension stone processing and the structure of the waste production process. Solid stone scraps and sludge were distinguished. On the basis of the performed analyses, it was shown that stone waste constitutes 10–35% in relation to the quantity of the processed stone material, with the quantity of sludge being even threefold greater than the volume of solid scraps. According to the circular economy principles, the aim should be to reduce the amount of waste generated by reducing primary resources in favour of secondary material. Reducing the volume of stone waste is possible through rational planning of stone production while at the same time maximising the efficiency of stone material usage and introducing the most modern processing machines. This significant volume of stone waste encourages efforts to find solutions for both its management and reduction. This paper reviews the utility potential of stone waste. Sensible use of waste is important to increase the profitability and productivity of processing plants while incentivising environmental protection.

Automation of the stone materials dosing process, controlled by variable frequency drives

<p>The objective of this article is to determine to what extent the automation of the stone materials dosing process, controlled by sequential drive of frequency variators, contributes to improving the productivity of a company dedicated to the production of asphalt in Peru for which, initially, the characteristics of the procedure that will lead to achieving the automation will be described. The results will then be displayed with respect to the indicators used to compare productivity before and after automation. The automation will be done by means of the logo 230RE controller, which will be connected to three frequency inverters, the programming development will be through the logo soft comford V8 software, for the sequential actuation, timers with connection delay will be used. Applying the automation, it is possible to improve the annual efficiency by an average of 58.30%, this is reflected in the monthly decrease in production time by 13.92%, in turn increasing the amount of stone material produced by an average of 43.77%. Likewise, it is possible to significantly reduce the production loss capacity by an annual average of 93.99%.</p>

On the initial velocity of the glacial-stone material movement, the air-blast, the nature of the carrier medium and the range of action of sudden explosion-like gas-dynamic surge of the Kolka glacier

Начальная массовая скорость компактного движения выброшенного ледово-каменного материала ледника Колка, достигнутая на стадии газового ускорения в эпицентральной зоне взрывоподобного внезапного газодинамического выброса ледника, составляла около 300 м/с. Именно столь высокие значения величины начальной массовой скорости выброса основного количества ледово-каменного материала определили возможность образования сопутствовавшей выбросу ударной воздушной волны, которая и на большом расстоянии от эпицентра выброса (порядка 15 км) все еще имела значительную интенсивность. Воздушным был характер несущей среды для всего Геналдонского лавинообразного потока в пределах выделенной прежде всего по этому признаку зоны транзита на всем многокилометровом ее протяжении, а для начальной и основной стадий выброса – и за пределами этой зоны (до Скалистого хребта). Дальность же действия взрывоподобного внезапного газодинамического выброса ледника Колка 20 сентября 2002 года, безусловно, не ограничивалась лишь вместилищем ледника Колка или Колкинским цирком, как иногда полагают, а захватывала огромную территорию Колкинского и Геналдонского ущелий и была ограничена (да и то не полностью) лишь непреодолимой механической преградой Скалистого хребта. Цель работы. В плане сопоставления с взрывоподобными направленными газодинамическими выбросами ледников рассматривается вопрос об истории изучения направленных вулканических взрывов, установленных полстолетием ранее. Методы работы. Проведен анализ имеющихся данных и существующих походов их оценок. Результаты работы. Показана огромная мощность взрывоподобных направленных газодинамических выбросов ледника Колка, вполне сопоставимых в данном отношении с крупными направленными вулканическими взрывами. The initial mass velocity of the compact movement of the ejected glacial-stone material of the Kolka glacier, reached at the stage of gas acceleration in the epicentral zone of the sudden explosion-like gas-dynamic surge of the glacier, was about 300 m/s. Exactly such high values of the initial mass velocity of the surge of the main amount of glacial-stone material that determined the possibility of the formation of an accompanying ejection of the air-blast, which had a significant intensity even at a great distance from the surge epicenter (about 15 km). The nature of the carrier medium for the entire Genaldon avalanche flow was aerial within the transit zone distinguished primarily according this character along its entire length of many kilometers; and for the initial and main stages of the surge the nature was the same outside this zone (up to the Skalisty (Rocky) Ridge). The range of action of the sudden explosion-like gas-dynamic surge of the Kolka glacier on September 20, 2002, was certainly not limited only by the reservoir of the Kolka glacier or the Kolka cirque, as it is sometimes supposed, but captured the vast territory of the Kolka and Genaldon gorges and was limited (and even then not completely) only by the insurmountable mechanical barrier of the Skalisty (Rocky Ridge). Aim. In terms of the comparison with explosion-like directional gas-dynamic surges of glaciers, the article considers an issue of the history of study of directional volcanic explosions determined half a century earlier. Methods. The analysis of the available data and the existing approaches for their assessments was carried out. Results. The results of the work show the enormous power of explosion-like directed gas-dynamic surges of the Kolka glacier, which are quite comparable in this respect with large directed volcanic explosions.

Facing Phototrophic Microorganisms That Colonize Artistic Fountains and Other Wet Stone Surfaces: Identification Keys

All fountains are inhabited by phototrophic microorganisms, especially if they are functional and located outdoors. This fact, along with the regular presence of water and the intrinsic bioreceptivity of stone material, easily favors the biological development. Many of these organisms are responsible for the biodeterioration phenomena and recognizing them could help to define the best strategies for the conservation and maintenance of monumental fountains. The presence of biological growth involves different activities for the conservation of artistic fountains. This paper is a review of the phototrophic biodiversity reported in 46 fountains and gives a whole vision on coping with biodeteriogens of fountains, being an elementary guide for professionals in the field of stone conservation. It is focused on recognizing the main phototrophs by using simplified dichotomous keys for cyanobacteria, green algae and diatoms. Some basic issues related to the handling of the samples and with the control of these types of microalgae are also briefly described, in order to assist interested professionals when dealing with the biodiversity of monumental fountains.

Study of the Behavior of Structural Materials Treated with Bioconsolidant

In this article, the effectiveness of the bioconsolidation technique applied to degraded structural materials is illustrated as a new method of consolidation and conservation of the existing building heritage in a less invasive way. Satisfactory results have been obtained by an experimental campaign carried out through non-destructive diagnostic tests, static destructive mechanical tests, and microstructural analyses on a series of natural stone material specimens and artificial stone materials before and after the use of bioconsolidants. The consolidated specimens have been tested after three to four weeks after the application of the M3P nutritional solution on each specimen. The effect on the microstructure of this technique has also been observed using scanning electron microscope and optical photomicrograph, the formation of new calcium carbonate crystals promoting the structural consolidation of the materials under examination was observed in all the specimens analyzed.

GEOLOGICAL NARRATIVE OF HISTORICAL GALICIAN CEMETERIES IN TERMS OF RESTORATION

The historic cemetery is an integral part of the architectural landscape of each city, the confirmation of ideology, the spiritual and economic life of its time. Cemeteries dating back to the second half of the 18th century have been preserved in many cities of Galicia. Now we call them historical cemeteries. Most of them are no longer in use and are filled not only with historical but also artistic monuments made mainly of stone. Such cemeteries require constant care and uninterrupted supervision. Preserving the physical substance of these cemeteries is a great challenge and a difficult task. To do this, it is necessary to conduct mineralogical and petrographic studies of the stone material of the historic cemeteries of Galicia. The state of preservation of natural stone, which is most common in the historical cemeteries of Galicia, was analyzed, the types of this stone damage were investigated. Also, preventive measures to preserve the stone material of the historic cemeteries of Galicia are proposed.

RESEARCH OF LOCALLY SOURCED STONE USAGE IN THE SCOPE OF SUSTAINABLE MATERIALS BASED ON EXAMPLES

There are many reasons for today’s environmental problems of today, the most important of them are the rise of construction industry based on population growth and and the increase of the waste that is generated by the growth of this sector. In particular, the amount of energy used in the production and application of the materials in constructions is one of the most important causes of the climate crisis that threatens our world. On the other hand, the emergence of designs compatible with nature to reduce the negative impact on nature has brought sustainability to the agenda. Ensuring the effective use of sustainable materials is one of the most important steps in this way. In the context of sustainable materials, stone material, which is frequently used in our traditional architecture has been addressed. Within the scope of this study, modern buildings which include locally sourced stone materials, were examined. The preference of local materials as building materials allows elimination of the energy which is consumed during material transportation and the carbon emission it creates. It is also valuable in terms of efficient use of energy and contributing to the local economy. A literature review has been made on sustainable architecture, sustainable use of materials and stone materials discussed within the scope of the study. According to that; "B2 House" and "Gökçeada High School Campus" buildings were examined in terms of local material usage. These structures are built with the support of the stone material offered by the geography, respectful to the traditional structure, and at the same time accommodating the requirements of modern life. The aim of this study is to reduce the energy consumption by encouraging the use of local materials in buildings in rural areas and to enable these structures to set a precedent for other buildings. With the development of technology, many unsustainable construction methods have emerged. As an alternative to these methods, it is aimed to increase the use of architectural methods compatible with nature. Acting in this direction, sustainability will provide gains in many areas. It is predicted that it will contribute to the local economy as well as adapting to nature. Key Words: Sustainable Architecture, Sustainable Material, Local Resource Usage, Local Stone Material Usage.

Evaluation of Wear Behaviour in Metallic Binders Employed in Diamond Tools for Cutting Stone

A type of disc-on-plate test methodology was used to determine the wear behavior of metallic binders employed in the manufacturing of diamond impregnated tools. The disc consists of a special circular wheel that allows the binder materials alone (i.e., without diamond, but sintered under conditions identical to those of the complete tool) to be tested against a plate of stone material under pre-determined testing conditions. The testing conditions are intended to be equivalent to those used in the industrial processes. Using plates of five types of granite and one type of marble, this work comprises wear tests of 15 different types of metallic binders and two sintering modes conducted under, at least, three different values of contact-force. The analysis of the results demonstrated that the wear of the binders can be related to their mechanical properties through an empirical expression. The larger the difference between the characteristics of the tribological pair (binder versus stone), the higher is the correlation between the experimental wear data and the values given by the empirical expression. The relationships presented in this work allow predicting the wear behavior of the binder, and therefore may help in the design process of diamond tools. There was a clear difference between the wear behavior of metallic binders when they were employed against the two main classes of stone under analysis (marble and granite).

Modelling the Leachability of Strontium and Barium from Stone Building Materials

In order that the impact on the environment and human beings can be assessed, it may prove necessary for geochemical research work to entail determinations of concentrations of trace elements in building materials, and it is also likely that this will be a time-consuming and financially-demanding business. Additionally, once basic research has been carried out to determine the mineral composition and structural and textural features, it will then be important to determine concentrations of elements that affect the surrounding natural environment and the health of human beings. This paper thus describes mineralogical and geochemical analyses performed on the stone material that opoka rocks represent. Mineralogical studies have shown that the studied opoka rocks most often have cryptocrystalline silica dispersed among carbonate components. The texture of the rock is slightly porous. Silica in the form of type opal A and CT (cristobalite–tridymite) is the main mineral component of the opoka rocks. Carbonate minerals represented by calcite were an important component in the opoka rocks. Earlier geochemical studies focused on the concentration of Sr and Ba. However, the determination of the leachability of these elements as a function of time is a novelty in this study. Trace elements leached from the material matrix were made subject to determinations. The MATLAB program was used to assess leachability in the cases of both strontium and barium, by reference to the Mamdani–Assilian fuzzy algorithm. The presented work has thus sought to experiment with the use of statistical methods to monitor the effectiveness of geochemical processes taking place over time.

Possibility of application of concrete sleeper with under sleepers pads

One of the most sensitive segments of the railway infrastructure are certainly bridges. All steel grid bridges have wooden sleeper attached to the bridge structure and cannot change the height when maintaining the upper structure rails. It has become a practice to reconstruct or replace damaged bridges in the past by taking care that the track construction is separated from the bridge constructions. One way is that steel grid structures are replaced with reinforced concrete structures in the form of a trough or if the spans are larger with steel structures in the form of a trough. The standard classical track construction today is a gangway with concrete sleepers and a ballast of crushed stone material. Such tracks have reduced elasticity, which is particularly important at contact between the sleepers and the stone material. In order to reduce the negative impacts of vibration and thus extend the durability of railway track today, railways increasingly apply concrete sleepers with under sleepers pads. Tests have shown that with the installation of the under sleeper pads it is possible to achieve a quieter passage of the train over the substrates of different stiffness, thus reducing the possibility of damage to the track construction and the vehicle itself.