This paper presents an examination of natural stone to slip resistance. The test is carried out according to the BAS EN 14231:2009 standard. This standard specifies a test method for determining the ...slip resistance value of the surface of the exposed face on natural stone elements intended to be used for flooring in buildings. The aim of the paper is to present the equipment, auxiliary means, samples and the test procedure. Tests are carried out on stone samples with different finishes. The test surfaces are: cut, polished and flamed. After the tests, the authors analyze and evaluate the obtained results. The results of this scientific research were presented for the first time as part of the 4th international symposium Herzegovina Land of Stone.
Deposits of dimension stone (hereinafter: DS) are mostly of heterogeneous composition and non-uniform properties. For the purpose of exploring the DS deposit, it is necessary to perform certain ...mining work in order to collect data for the determination of: existence, position and shape of the bed, quantity and quality, and the conditions for exploitation of DS. The position and shape of the deposit have a crucial influence on DS exploitation conditions. Discontinuities of different positions, dimensions and shapes were formed as a result of dynamic and chemical processes in the rocks. The exploitation of DS from the deposit is performed by obtaining as geometrically regular and as large in size blocks as possible. The DS exploitation should be harmonized with the position and shape of the deposit as well as discontinuities for the purpose of obtaining the highest possible exploitation of stone. However, a special requirement of construction is to obtain the DS, primarily of uniform appearance and other properties. Therefore, it is necessary to optimize mining works for the purpose of obtaining and installing DS of a uniform appearance, as described and shown on several examples in this paper.
Diamond wire saws are indispensable machines for the extraction and processing of dimension stones. The cutting speed, energy consumption and wear rate of the diamond beads are the most important ...factors in assessing the efficiency of a diamond wire saw. The parameters that influence the efficiency of the diamond wire saw can be divided into controlled and uncontrolled parameters. Uncontrolled parameters cannot be influenced directly and are related to the rock types and their properties such as strength, hardness and abrasiveness. Controlled parameters are related to the operating parameters and technical characteristics of the machine. The energy consumption and the service life of the diamond wire are directly related to the characteristics of the machine and the design of the diamond wire, such as the power of the drive motor, the diameter of the drive wheel, diamond grit size and the diameter of the wire. The operating parameters of the diamond wire saw, such as cutting speed, cutting surface, cutting angle, wire tension and cooling water flow, also have a significant influence. Based on previous studies, the influence of the above parameters on the consumption of energy and wear rate of diamond beads in the operation of a diamond wire saw was analyzed.
In Kurdistan NE of Iraq extensive beddings of well bedded carbonate rocks deposited within Tertiary- Cretaceous age. For this purpose various studies of petrographic, physical, mechanical, and ...chemical properties for building construction were carried out. Appearance of rocks was measured in the field by thickness of the beddings, joints, fractures, and brightness. The petrographic study achived under transmitted light microscope for diagenesis, weathering, allochems, and matrix. Measuring specific gravity, density, water absorption, moisture content, porosity, and saturation coefficient to qualify the rock according to its physical properties, whereas measuring compressive strength of the rocks were determined for qualifying the mechanical properties, the XRF test for determining the oxides and durability tests for qualifying their chemical properties. Eleven samples selected from Qamchuqa Formation in Binabawi anticline, Aqra-Bekhme Formation in Shakrok anticline, Shiranish Formation in Pirat anticline, Shiranish Formation in Harir anticline, Shiranish Formation in Safin anticline, Shiranish Formation in Shakrok anticline, Pila Spi Formation in Pirmam anticline, Khurmala Formation in Bina Bawi anticline, Fatha Formation in Kori syncline, Anah Formation in South Qara Chugh anticline, and Euphrates Formation in North Qara Chugh anticline. The results in terms of economic demand for building and dimension stones showed that samples of Shiranish Formation from Pirat, Safin, Harir, and Shakrok anticline are highly recommended as dimension stone and building stone, while samples of Qamchuqa, Aqra-Bekhme, Pilaspi, Khurmala, and Euphrates Formations are accepted but not recommended as dimension stone and dimension stone, samples of Fatha and Anah Formations are not accepted as dimension stone, but accepted as building stones as an insulator.
Long-term experimental (bio)weathering revealed that Fe-rich sandstone was more susceptible to biodeterioration as compared to Fe-depleted sandstone. Leaching data combined with surface observations ...indicated higher susceptibility of goethite (FeOOH) than hematite (Fe2O3) to dissolution. Organic-rich weathering conditions were found to have a larger impact on sandstones as compared to inorganic weathering. Element release from the mineral lattice can be largely enhanced by organic conditions affecting dissolution of hematite cement and changing stoichiometric proportions of elements initially bound in matrix and cement minerals. This study highlights that long-term episodes of biotic and abiotic weathering constitute key factors affecting susceptibility of sandstones to degradation processes.
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•Bacteria and siderophore enhance weathering of sandstones.•Organic-rich conditions facilitate weathering of sandstones.•Sandstone cement was the most susceptible component to dissolution.•Goethite is more susceptible to dissolution than hematite.
Dimension stones industry is an industry with significant economic potential that has been overgrowing in recent years. Despite this growth, this industry faces several significant challenges, ...including very low efficiency, high production costs, and many wastes generation and resource loss during extraction and processing phases. To overcome these issues, further studies are needed to discover the causes of these problems, determine how to update existing technologies, replace them with more efficient alternatives, and find out how to use new and advanced optimization methods in dimension stones exploration and extraction and processing procedures. Regardless of the approach, these measures' primary purpose should be to achieve better results in recovery rate, production costs, resource loss, and waste generation. In this paper, the amount of waste generated in different phases of the dimension stone production process was investigated. This investigation showed that about 51% of all the material extracted from dimension stone quarries turns into waste during the extraction operation, and roughly 41% of the material that arrives at dimension stone processing plants turns into waste during the processing operation. Therefore, the overall recovery rate of the dimension stone production process is approximately 29%, signifying the significant volumes of resources lost and the large amounts of waste generated. The paper also discusses the types of waste generated in different phases of the dimension stones production process, production factors in each case, and solutions that can be adopted to minimize waste generation in each phase of this industry.
•Comparison of original quarry and monument samples enables to establish the decay mechanisms.•In situ salt formation in serpentinites under different environmental conditions is observed.•Salt ...formation due to the presence of sulfides is the main cause of decay.•Identification of all the factors that act synergistically in serpentinite stone decay.•Measures to avoid deterioration are proposed.
This paper presents a thorough study of the main features and the decay causes and mechanisms of serpentinites both freshly quarried and after centuries exposure at the main façade of the sixteenth century Royal Chancery (Granada, Spain). In particular, the process of in situ formation of calcium and magnesium sulfates has been studied. Several decay factors are identified, all of them acting synergistically in the deterioration of slabs made of serpentinite. Among them, chemical weathering of sulfides such as pyrite present in the original serpentinite induces the formation of sulfate salts such as gypsum or epsomite, salts which are considered the main cause of decay. In addition, unsuitable restoration treatments involving the use of Portland cement to fill up cracks and surface lacunae, the polluted environment of the surrounding area, and the location of the slabs close to the ground, favoring capillary rise of water, all contributed to their deterioration. This work helps to gain knowledge on the deterioration process of ornaments made of serpentinite, allowing us to propose the most appropriate measures to guarantee their conservation.
Granite is found in many world heritage monuments and cities. It continues to be one of the most widely used stones in today's construction, given its abundance, uniformity and durability. Quarrymen ...traditionally cut this rock along its orthogonal slip planes, where splitting is easier. Ranked by ease of splitting, these planes are rift, grain and hardway. Granite is traditionally quarried along the rift plane where coplanar exfoliation microcracks coalesce developing a flat surface. This splitting surface minimizes the cost and effort of subsequent hewing. Rift plane was predominantly used on the fair face of ashlars in heritage buildings worldwide. Determining the petrographic and petrophysical behaviour of these three orthogonal splitting planes in granite is instrumental to understanding decay in ashlars and sculptures. The decay of building granite is different in each splitting plane.
Alpedrete granite was the stone selected for this study based on the orientation and distribution of exfoliation microcracks and the characterisation of their implications for the anisotropy of petrophysical properties such as ultrasonic wave propagation, capillarity, air permeability, micro-roughness and surface hardness. Inter- and intracrystalline microcrack length and spacing were also measured and quantified.
The findings show that the splitting planes in Alpedrete granite are determined by the orientation of exfoliation microcracks, which as a rule are generally straight and intracrystalline and determine the anisotropy of the petrophysical properties analysed.
Splitting planes are the orientation that should be applied when performing laboratory tests for the petrographic and petrophysical properties of building granite.
•The splitting planes of granite are controlled by the exfoliation microcracks.•The exfoliation microcracks condition building granite anisotropy.•The decay of building granite is different in each splitting plane.•The analysis of exfoliation microcracks with fluorescence microscopy allowed to study their characteristics.•Splitting planes are the orientation that should be applied when performing laboratory tests of building granite.
Fire accident is a common and serious damage phenomenon affecting tunnels, historical sites, buildings, monuments, etc. However, the understanding of the thermo-mechanical behaviour of rocks during ...fire and the corresponding damage on the rocks is still limited. In this study, the thermo-mechanical behaviour of Eibenstock granite under the temperature of 400 °C and 800 °C was studied applying heating rates of 5 °C/min, 200 °C/min, 300 °C/min, and according to ISO 834 standard fire curve. A supersonic frequency induction heating system was used to conduct the required heating scenarios and to perform uniaxial compression tests under the desired temperatures. A threshold modulus Ec obtained from dividing peak axial stress by the peak axial strain is defined to characterize the stiffness of the sample at various temperatures. Both tangent Young's modulus and threshold modulus are greatly influenced by maximum temperature, while the influence of heating rate is relatively small. The maximum temperature has the dominant impact on the uniaxial strength of granite sample, while the influence of heating rates is again negligible. The peak axial strain increased obviously with rising temperature. It first increases at 200 °C/min heating rate and then reduces slightly in scenarios with heating rate of 300 °C/min or heating according to ISO 834. The observed failure modes after uniaxial compression tests are influenced by peak temperature and heating rates. The granite specimen can be crushed in the shape of blocks, fragments or powder. The deduced friction angle for various heating scenarios is more or less consistent, while the cohesion shows a strong temperature-dependent characteristic. Although the cooling process can lead to an increase in crack density, UCS, peak axial strain and cohesion are enhanced at lower temperatures. The presented results help to understand the damage mechanisms of granite caused by fire, and can be used to develop guidelines for repair and maintenance as well as assessment of risks of tunnels and historical buildings after fire accidents.
•Special designed high speed heating incl. Non-linear ISO 834 fire curve.•Maximum temperature has dominant impact on granite properties.•Influence of heating rate is relatively small and negligible.•Friction angle is neither temperature- nor heating-rate dependent.
There is a lot of evidence that people used stone in the construction of buildings, as well as for other purposes in the municipality of Livno throughout history, as evidenced by numerous ...archaeological finds. Ever since the Bronze and Iron Ages, and through the Roman, medieval and Turkish periods, stone has been the main building material in these regions. In recent times, two dimension stone quarries have been opened on the territory of the municipality of Livno, one in the locality of Pogledala, east of the city, and the other in the locality of Kik, located between the Kamešnica and Dinara mountains. Both quarries were opened in massive limestones of Upper Cretaceous age. High-quality limestone with the commercial name "Silit light" is being exploited at the Pogledala quarry, and at the Kik site exploitation has been interrupted, but there is a great possibility of its continuation.
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