Granite Stone Research Articles

Adult Sports Participation and Physical Activity: How About Curling?

Despite its well-documented physical and psychosocial benefits, sport remains the least engaged form of physical activity (PA) among adults. Many adults may lack the skills needed to play or continue to play sports and aging adults are more likely to avoid participation for fear of poor performance or injury. A sport that shows great promise for adults seeking new sports participation outlets is curling. Curling is a team sport comprised of four interchangeable positions working collectively to deliver granite stones across a sheet of ice in an effort to outscore the opponent team. While it seems reasonable that walking on ice, “throwing” a 44 lb granite stone across a sheet of ice, and periodically sweeping while walking on ice over a two-hour period would generate at least a moderate amount of physical activity, research to date is quite limited. Therefore, the purpose of this study was to objectively measure the amount and intensity of PA achieved by average recreational curling participants during a typical curling match. Methods Members of a curling club in NC were asked to wear Actigraph Accelerometers (model GT3X) while they participated in their regularly scheduled curling match. All participants had at least one year of curling experience. Curling matches lasted between 90 and 120 minutes. Participants were asked to indicate their age, gender, and curling position during the match (lead, second, vice, skip) which were matched with accelerometer data. Results Overall, 110 participants (37 female, 73 male, avg. age 50 yrs) spent most of their curling time in light or moderate-intensity activity (18.1% Sedentary; 49.5% light; 32.4% moderate; .03% vigorous). In terms of minutes, the average participant spent 35.9 minutes engaged in Moderate-to-Vigorous PA (MVPA) per curling experience. This represents 23.9% of the weekly 150min of MVPA suggested by the CDC. The second position had the highest percentage of moderate activity level and a small percentage of vigorous activity. No other position reached a vigorous level. The skip position had the highest amount of sedentary activity as well as light activity. Females had a higher level of moderate activity in comparison to males. However, males reached a small amount of vigorous activity. The age group of 18 - 36 had the highest amount of moderate activity and the lowest amount of sedentary activity. This age group reached an average of 41.0 minutes of MVPA per curling experience. The age group of > 58 had the highest amount of sedentary activity and the lowest amount of moderate activity. Conclusions Curling may be a good sports participation option for adults looking for alternatives to meet recommended weekly amounts of MVPA. Participants should consider playing in one of the first three positions to maximize the amount and intensity of PA achieved while playing. Furthermore, since curling also requires balance, coordination, muscular strength, multitasking, strategic reasoning, and can cater to most physical challenges without compromising the integrity of the game, it may be an ideal sport to promote for adults of all ages and sport abilities. Implications for Practice and Policy Findings should be used to inform strategies for promoting curling as an opportunity for team sport involvement that has the added value of contributing to daily physical activity. However, , access and opportunities to play, especially for underserved populations, are limited. Given that most curling clubs in America are private and require a membership to play. Partnership arrangements between existing clubs and public parks and recreation departments could increase both access and opportunities to play.

Stabilization of lateritic soil with Portland cement and crushed granite for pavement base courses

The aim of this work is to propose reconstituted materials, by cement-based improvement of lateritic gravels and joint cement improvement and lithostabilization, that are technically suitable for use in base courses. The study focused on two (02) different lateritic gravels, LG1 with a fine content of 24% and LG2 with a fine content of 15%. For lithostabilization, 0/25 granite crushed stone was used and the cement used was CEM II/B-LL 42.5. For cement improvement, three (03) cement contents (1%; 1.5% and 2%) were studied, and for joint stabilization, the granite crushed content was set at 10%, with only the cement content varying by 1%, 1.5% and 2%. The mixes were obtained by adding the cement mass calculated from the total gravel mass collected and the cement rate studied to the raw gravel or to a mixture of 90% gravel and 10% granite crushed stone. The results of physical-mechanical tests such as the Atterberg limits, Modified Proctor and California bearing index of stabilized materials were analyzed in comparison with the initial values of raw materials without stabilization. The results show that cement increases the plasticity index but improves the bearing capacity of lateritic gravels better than joint stabilization. However, joint stabilization does improve gravel bearing capacity compared with untreated raw gravel. For use as a base course in accordance with CEBTP specifications [3], in addition to the 10% granite crushed content, LG1 must be upgraded to at least 1.5% cement and LG2 to 1%.

Characterization of Marble and Granite Processing Waste and its Utilization in Brick Production: Case of Saba and Semayata Dimensional Stone Companies, Tigray, Ethiopia

In Ethiopia, the marble and granite dimension stone industries have been growing significantly in the last decade and have become a part of the flourishing construction industry. Accordingly, the amount of quarrying and processing has increased significantly. This has contributed to increased waste of time. Semayata and Saba Dimensional Stone plc are the leading dimension stone-based companies located in the Wukro and Adwa areas, respectively in the Tigray region are involved in producing tiles and slabs of marble and granite. Due to its processing techniques and its highly alkaline nature, marble, and granite wastes in the Adwa and Wukro areas have become causes for environmental problems. Consequently, the demand for the recycling of waste has come to the forefront due to both environmental and financial considerations. Keeping this in view, a study was conducted on the waste generated by the Saba and Semayata processing units. The study aims to characterize wastes; and discuss the possibilities of using marble and granite wastes as an alternative raw material in the production of bricks. Based on the chemical, physical, and mechanical properties, the waste can be used to produce bricks without modifying and adding other contents.

Rheological properties of high-performance SCC using recycled marble powder

Due to the impacts of cement manufacturing and depletion of the natural aggregates for concrete production, recycling of construction and demolition waste materials has become an alternative replacement to natural materials that lower their consumption and satisfy the environment. One of these alternatives is replacing cement with recycled materials from marble, ceramic, granite, and concrete wastes or even replacing the coarse aggregate with crushed marble and other stone wastes. Marble, granite, and natural stone wastes rapidly increase each year due to unmanaged waste disposal processes and the incremental increase in construction potential. Marble slurry, which comes from washing and cleaning marble surfaces, shows a filler effect by giving the concrete a denser and homogenous structure. This study evaluates the marble filler effects on the rheology in the fresh state of self-compacting concrete (SCC) through four SCC mixes by incorporating 10% marble powder (MP) and 33% fly ash (FA) as a partial ordinary Portland cement (OPC) replacement. Tests on paste and mortar were conducted to assess the suitability of the marble dosage on the water content and the superplasticizer amount. Spread flow and V-funnel tests were assessed. The results showed that mixes with MP required additional mixing water to ensure the same workability. Regardless of the high viscosity and air content, the overall developed marble SCC mixes reduced the cement quantity by up to 11% and provided excellent rheological properties like that of the reference mix. Besides the economic benefits, this transformation of waste to valuable materials involves environmental advantages and sustainability promotion.

Between Smart Images and Fast Trucks: Digital Surveillance and Obscured Labour in Hyderabad, India

In Hyderabad, India, the growing information technology (IT) sector relies on ensuring safe and efficient movements of people and objects, and the city government and private actors have embraced the promise of digital surveillance to reach these goals. The new Telangana State, created in 2014, has built a new city-wide network of smart cameras, and at ‘hackathons’ programmers develop new digital tools, often connected to this network, that will technologically ‘solve’ social problems. In this article, I examine the system of CCTV cameras and programmers’ investments in these systems, and explore how migrant Vaddera stonecutters use cellphones to evade patrolling officers monitoring the streets where they carry the granite stones that they cut and load to construct the city’s buildings. Expanding on what Gilbert Simondon calls ‘the margin of indeterminacy’, this article reveals gaps in the digital infrastructure of surveillance—even as its integration and completion combine human and technical elements.

Study of the Geochemical Decay and Environmental Causes of Granite Stone Surfaces in the Built Heritage of Barbanza Peninsula (Galicia, NW Spain)

Study of the Geochemical Decay and Environmental Causes of Granite Stone Surfaces in the Built Heritage of Barbanza Peninsula (Galicia, NW Spain)

Performance analysis of solar desalination using crushed granite stone as an energy storage material and the integration of solar district heating

ABSTRACT This study explores the feasibility of solar desalination using black powder coated crushed granite stone, evaluating their energetic, exergetic, and economic aspects, wherein the stone bed preheats water for the solar still. In addition, the system integrates with a district heating network to meet desalination needs during off-solar or high-demand hours in which water from the powder-stone grid’s outlet flows through a heat exchanger, powered by district heating’s return flow. Desalination pipe absorbs heat and cools district heating line. The outcomes illustrated that cumulative distilled water for a water depth of 1 cm was 13.1% and 28.2% higher than cumulative distilled water for water depths of 2 cm and 3 cm, respectively. The energy efficiency was improved by 9.5% and 15.7% and the exergy efficiency was enhanced to 13.6% and 27.2% at 1 cm water depth compared to 2 and 3 cm water depths. The integration of the system with the district heating network could lead to a great improvement in the productivity; summer’s low district heating demand allows surplus heat to boost water production and lower outlet water temperature, benefiting both desalination and cooling process. The cumulative productivity will not be sensitive to the water depth anymore, increasing up to 105%, 135%, and 182% for 1, 2, and 3 cm water depths, respectively. This integration has a fascinating effect on the reduction in temperature of the district heating return flow (about 3°C), improving the cooling potential of the flow.

Analysis of the Resistance of Self-Compacting Concrete (SCC) with the Use of Granite Stone Waste to Alkali-Silica Reaction

Aggregates occupy ±70% of the concrete volume and their quality must meet specifications. Concrete surfaces submerged in water for a long time cause concrete failure due to the reaction between aggregate and cement to form silica gel. The wear value of granite is less than gravel, so this study used granite as a substitute for coarse aggregate. This study was conducted to assess the resistance of SCC concrete with 0%, 25%, and 30% granite stone variations to alkali-silica reaction attack. The experimental method was applied to the study with ACI method mix design as well as 25 MPa plan fc'. Concrete cylinder samples 150 mm x 300 mm aged 28 days were used in the compressive strength test, alkali-silica reaction expansion test used mortar block samples 285 mm x 25 mm x 25 mm in 80±2˚C NaOH solution bath for 14 days. The optimum compressive strength of 32.17 MPa and the lowest percentage change in length of 0.04% was obtained by sample BG.25-SCC, indicating that granite stone is not reactive to silica alkali reaction because the percentage change in length <0.10%. This study concludes that granite stone can improve the resistance of concrete to silica alkali reaction.

Experimental Studies on Paver Block Concrete using Granite and Kota Stone Waste with Environmental effects on Strength

The need to address the worldwide demand for the preservation of limited resources has prompted the exploration of alternate materials. The application of waste materials in the concrete sector is experiencing a growing trend due to its potential to mitigate costs and minimize environmental repercussions. This study aims to assess the appropriateness of utilizing waste materials from granite and Kota stone for the production of interlocking concrete paver blocks (ICPB). The current study examines the potential use of waste materials from granite and Kota stone as substitutes for natural aggregates in the production of concrete interlocking paving blocks. The focus is on applications that cater to pedestrians and non-traffic scenarios. Concrete blocks of M30-grade were cast for this study. The replacement percentages were ranged from 0% to 100% for Kota stone as coarse aggregates and from 0% to 40% for granite waste as fine aggregates and total of 543 samples were cast using the replacement level. The mix proportion ratio used was 1:1.57:2.76 (cement: sand: aggregates) while continuing a constant water-cement ratio of 0.45. Weathered Kota stone waste (0, 25, 50, 75, 100%) was also used as anauxiliary for coarse aggregates in M30-grade concrete. The tests conducted covered the physical characterization of the constituent materials, determination of compressive strength, split tensile strength, flexural strength, abrasion resistance, and water absorption tendency for both hardened concrete blocks and I-shaped interlocking pavers. The result indicates that while using stone waste (granite and Kota stone), the required compressive strength was achieved up to a replacement level of 100% Kota stone and 5% granite waste. Flexural strength and splitting tensile strength were also satisfactory at all replacement ratios, along with normal water absorption and minimum abrasion. Paver blocks were also cast from waste stones at various replacement levels. In this study, concrete blocks were also cast using weathered Kota stone waste, which also provided sufficient strength at some level of replacement. The findings suggest that waste stone may be a viable option for manufacturing interlocking pavers, contributing to the development of an environmentally conscious and sustainable pavement infrastructure.

Preventive geochemical barriers during transport construction

The article discusses the possibility of using chlorite crushed stone as part of geochemical barriers in transport construction. It has been shown that during the construction of railways and during their operation, the main pollutants are petroleum products and heavy metal ions. To substantiate and study the neutralizing properties of chlorite crushed stone, infrared spectroscopy, ionomer, atomic absorption spectrometry and the gravimetric method for determining petroleum products were used. Research has shown that chlorite crushed stone is a quartz-albite-chlorite shale with a small inclusion of carbon; its physical and mechanical characteristics are not inferior to granite crushed stone. The oil capacity of chlorite crushed stone depends on the concentration of petroleum products in the model solution and ranges from 0.03 to 0.5 g/g. Chlorite crushed stone has a capacity towards nickel, iron and cadmium ions, while their simultaneous presence in the model solution does not have selectivity towards these ions. It has been proven that when the capacity of chlorite crushed stone is fully realized in relation to one of the heavy metal ions, it is not washed out and replaced by another metal ion (for example, nickel and iron ions). It has been proven that the presence of organic contaminants in the model solution does not significantly affect the capacity of chlorite crushed stone for heavy metal ions. It has been shown that chlorite crushed stone, due to its physical, physical-mechanical and chemical properties, can be used in geochemical barriers to protect the environment from pollution.

Automation of primary crushing control

The article deals with issues related to the synthesis of an automatic control system for a jaw crusher, for which the main control and disturbance channels were identified and its mathematical model was obtained. Implementation of mechanization and automation systems at crushing and screening plants is necessary for the production of granite crushed stone, which is massively used in the construction of agricultural facilities. Based on the analysis of the mathematical model, a decision was made to choose the law of regulation and its parametric identification was carried out. Analysis of the quality indicators of the regulation of the synthesized system revealed their significant dependence on the disturbing effect, which required the synthesis of a disturbance compensator, the inclusion of which in the structure of the system made it possible to realize the requirements imposed on it.

Laboratory testing and model calibration of a crushed stone backfill in a geosynthetic reinforced soil wall

The objective of this study was to understand the effect of the choice of backfill constitutive models on the numerical simulation of a geosynthetic reinforced soil-integrated bridge system (GRS-IBS). The #89 material, a crushed angular granite stone, characterized by maximum particle sizes of 9 mm, was used for the reinforced backfill for the retaining wall. Consolidated drained triaxial tests were conducted at confining stresses of 48 kPa, 83 kPa, and 117 kPa. The average friction angle was 42 degrees. Two soil models (the linear-elastic perfectly-plastic and the Hardening Soil) were calibrated using the laboratory test results. The calibrated soil models were then used to model the reinforced backfill material in finite element simulations of the abutment. Results of the calculated vertical stresses at the instrument position showed reasonable agreement with the field measurement. The non-linear model predicted about twice the deformation (lateral displacement and bridge seat settlement) compared to the linear-elastic perfectly plastic model. Settlement results showed maximum values corresponding to 0.22% and 0.45% of the abutment height for linear-elastic perfectly-plastic model and Hardening-Soil model, respectively, which are less than 0.5% limit recommended by US FHWA, while the lateral displacements were 0.22% and 0.44% of the abutment height for linear-elastic perfectly-plastic model and Hardening Soil model, respectively, both less than the 1% limit recommended by the US FHWA.

Corrigendum to: Analysis of the Resistance of Self-Compacting Concrete (SCC) with the Use of Granite Stone Waste to Alkali-Silica Reaction

Corrigendum to: Analysis of the Resistance of Self-Compacting Concrete (SCC) with the Use of Granite Stone Waste to Alkali-Silica Reaction

Evaluating the Weathering Effect on Granite, Limestone and Uncrushed River Stone Aggregates for Road Constructions

The lack of excellent aggregate materials has become a major issue in Sarawak. River stone, abundant in many places of Sarawak, can be used as an alternative aggregate material, minimising the reliance on high-quality aggregates like granite in the production of an affordable and sustainable road pavement. Weathering also deteriorates aggregate materials. This project aims to investigate the durability of granite, limestone, and uncrushed river stone aggregates with regards to weathering effects. The aggregates are subjected to two conditions, i.e., normal condition (without wetting and drying cycles) and wet-dry condition (with wetting and drying cycles). The physical properties of aggregates are determined by the Flakiness Index, Elongation Index, and Specific Gravity. Weathering effects on aggregates are determined using laboratory tests such as Aggregate Impact Value (AIV), Aggregate Crushing Value (ACV), and Los Angeles Abrasion (LAA). Weathering cycles have been found to have a minor impact on aggregates in the short term. Overall, the test results indicate that wetting and drying circumstances have a negligible effect on aggregates over a short period of time. The materials' physical attributes all meet JKR requirements. The Aggregate Impact Value (AIV), Aggregate Crushing Value (ACV), and Los Angeles Abrasion (LAA) values are nearly constant across the wet-dry state for all aggregate kinds. Despite the wet-dry situation, the AIV, ACV, and LAA tests demonstrate that specific aggregate materials retain their durability when compared to other aggregate materials. As a result, granite is the most durable aggregate in terms of AIV and LAA when compared to limestone and uncrushed river stone, while uncrushed river stone is more durable in terms of ACV when compared to granite and limestone.

RESEARCH ON THE PHYSICAL PROPERTIES OF THE BUILDING STONES IN EAST BLACK SEE REGION

This study investigated the physical properties of Ünye stone (Ordu), Harşit granites (Giresun), and Trabzon gray stone (Trabzon) used as building materials in the Eastern Black Sea Region. Chemical components, thermal conductivity, compressive stress, water absorption, and abrasion percentages were determined. Ünye stone has small thermal conductivity coefficient values (0.67 W/mK), indicating that it can be used for thermal insulation and decorative purposes as briquettes, bricks, or wall cladding materials. Harşit granites have compressive stress and abrasion rate values of 113 MPa and 1.05%, respectively. Trabzon gray stone has compressive stress and abrasion rate values of 125 MPa and 1.13%, respectively. These results indicate that Harşit granite and Trabzon gray stone can be used as wall cladding materials and wear-resistant floor coverings. These three stones can be widely used because they are cheap and abundant.

Method of evaluation of pavement bitumen adhesion

The durability of an asphalt concrete pavement largely depends on the quality of the bitumen binder and the strength (or degree) of its interaction with the surface of aggregates (adhesion). The method is based on the finding of bitumen adhesion with a reference substrate, which is taken to be glass. The article presents the results of obtaining the adhesion to the glass surface: bitumen of different grades; bitumen modified with various additives; bitumen modified with adhesive additives and hardened by various methods. The results of comparing the adhesion of bitumen to the glass surface with the results of the Rolling Bottle Test are presented. It has been proved that, with a certain assumption, the value of adhesion to the glass surface can be taken as indicative value for the adhesion of unmodified bitumen to the surface of granite stone materials, obtained after 6 h of testing by the Rolling Bottle Test.

The regulation of mechanical properties and freeze-thaw properties of concrete hollow block with granite waste

ABSTRACT Owing to the generation of waste during mining and processing, granite stone causes great damage to the environment. In this study, the broken granite waste and the stone powder were used as concrete coarse aggregate and “admixture” to make granite waste concrete hollow blocks, which could meet the requirements of compressive strength, durability and economy. The influence of the water-binder ratio, cement dosage, and powder-slag ratio on the compressive strength and freeze-thaw properties of the block were analyzed. Subsequently, the optimal mix ratio was determined based on range analysis. The effect of granite waste on the compressive strength and durability of the blocks was also analyzed. In addition, the economic effects of the granite waste concrete hollow block were analyzed. The results show that granite waste concrete hollow blocks with a water-binder ratio of 0.55, powder slag ratio of 15%, and cement dosages of 340 kg/m3 and 320 kg/m3 can meet the strength requirements of MU10 grade and the requirements of freeze-thaw properties. The strength and frost resistance of the granite concrete hollow blocks were enhanced because the granite powder filled the aggregate gaps. In addition, the price of granite concrete hollow blocks was reduced by approximately 50%. The small hollow block of granite concrete is environmentally friendly and worth promoting.

A Preliminary Study Was Conducted on the Compressive Strength and Flow Performance of Environmentally Friendly UHPC-SCA

This research paper explores using marine shells as coarse aggregates in producing seawater sea sand UHPC-CA. The study examined factors such as coarse aggregates (granite, oyster shell, and cone shell), fine aggregates (sea sand and river sand), fiber types, and content. The research findings indicate that different coarse aggregates and fibers influence the flow performance of UHPC-SCA. The study identified the cone shell as the best coarse shell aggregate and 1.5% steel fiber as the optimal fiber and inclusion amount. The compressive strength of this combination reached 106 MPa, which is comparable to the granite stone UHPC-CA of the same particle size.

Evaluation of the influence of linear stress concentrators in reinforced concrete elements using the postulates of fracture mechanics

The article is devoted to the study of linear stress concentrators in reinforced concrete, which, unlike randomly located stress concentrators from a large and medium-sized concrete aggregate (granite or gravel crushed stone), can have a strategic impact on the formation of cracks in a reinforced concrete element in the presence of a sufficient level of tensile stresses. The study is one of the theoretical parts of a significant research program on the cracking of reinforced concrete elements in tension and bending. The description of the process of cracking with the help of fracture mechanics allows us to try to formulate a mathematical apparatus for taking into account stress concentrators linearly located in reinforced concrete elements and their influence on the formation of cracks, in particular, at the moment of cracking in bending elements. Field tests of specimens with artificially created stress concentrators were carried out, including the RILEM method, on the basis of which trial calculations of the cracking moment were carried out using the stress intensity factor.

Thomas Henry Huxley, a stone tablet, coccoliths, and deep-sea sediments in the high Alps

AbstractIn the mid-1850s, Thomas Henry Huxley, who coined the term ‘coccolith’, described their presence in oceanic sediments dredged from the sea floor. Subsequent recognition of their occurrence in the Upper Cretaceous English Chalk, largely unconsolidated pelagic sediment, and similar, more lithified limestones in the Jurassic of the Alps, led to their being considered major rock-forming elements through much of geological time, although they are now known to be limited to the Late Triassic–Recent interval. Unlike Charles Darwin, who did not travel abroad following the voyage of the Beagle, Huxley made a number of trips to Italy and Switzerland and is recorded as a guest in the exclusive Hotel Kursaal Maloja in the Engadin in 1893. While staying there, he made a number of excursions on foot and his presence was thought significant enough that it is recorded in an inscribed granitic stone tablet, erected in 1896, describing him as’the illustrious writer and naturalist’. His rambles would have led him past outcrops of tectonically emplaced true oceanic calcareous sediment of Early Cretaceous age, here shown to have originally contained coccoliths that were largely destroyed under the imprint of Alpine metamorphism of sub-greenschist to greenschist facies. To this extent, Huxley could have come close to recognizing true oceanic sediments exposed on land, but the dissimilarity between these Swiss Alpine deposits and the friable English Chalk would not obviously have led to the investigation of the former for the organisms he had christened as ‘coccoliths’.