Natural Stone Research Articles

Effect of Different Admixtures on Mechanical Properties of Concrete Paving Block: A Comparative Study

Ever since their introduction nearly a century ago, concrete paving blocks have become increasingly common. They evolved into an alternative to burned clay brick and natural stone. Concrete paving blocks are used to lay down areas for vehicles and pedestrians as well. Durability is one of the most crucial elements in the production of high-quality concrete paving blocks. The aim of this study is to optimize the mechanical properties of concrete paving block units by experimenting with different admixtures. Compressive strength, water absorption, oven dry density, and drying shrinkage are among the attributes that were evaluated. The cost of production was also contrasted with and without the use of an admixture to achieve a comparable compressive strength. The results showed that admixtures could be used to produce high early strength units, and this was considered to be an economical factor in the production of concrete paving block units. At all ages, the use of admixtures increased these units' compressive strength by 30–40%. Although they did slightly increase density, additives also decreased the absorption and drying shrinkage of concrete paving block units.

Experimental investigation into effects of natural stone properties on performance of a chisel tool

ABSTRACT The main purpose of this study is to determine how the linear cutting experiments should be performed on natural stones to better understand the stone cutting and predict cutting performance parameters from easily obtainable rock properties. A compiled database including thirty-four different natural stone samples in metamorphic, sedimentary and igneous geological origins is used to investigate the relationships between specific energy, mean normal and cutting forces and eleven different macro and micro properties of natural stones collected from quarries around Turkey. Linear cutting tests are performed by a portable linear cutting machine with a simple chisel tool at four different depths of cut in unrelieved (non-interactive) cutting mode. The difference in this study from previous investigations is the wide variety of stone samples with different characteristics to better explain the cutting mechanisms of natural stones. The results indicate that Shore scleroscope hardness and texture coefficient can be used to predict cutting performance parameters of natural stones. Additionally, using shallower depths of cut in linear cutting tests could lead to a better explanation of specific energy of natural stones.

Life Cycle Cost Analysis and Deterioration Patterns of Limestone Paving

Stone is a durable and high-performance paving material in standard and in intensive service regimes. Stone is thus a preferable material for sidewalk and promenade paving under intensive service regimes, such as touristic promenades and historic sites. Recent studies on the weathering and degradation of stones in buildings have revealed differing analytical approaches among geologists, geo-engineers, and civil engineers. The present research aims to develop a structured analytical–empirical methodology for the assessment of stone pedestrian pavements’ life cycle and life cycle costs. This study presents an integrated methodology that combines diagnostic field surveys, core laboratory tests, and the characterization of deterioration patterns. This approach allows for evaluating how faulty construction methods impact the durability and degradation of natural stone pedestrian pavements. It also assesses their effect on the pavement’s life cycle and associated costs. The diagnostic field survey concentrates on specific construction details, including: (a) Cracks in the paving stones. (b) Peeling of stone layers. (c) Subsidence and cracking at the paving edges. (d) Cracking of filler materials in joints between stone slabs. The laboratory tests focus on five core physical properties for the stone deterioration: (1) apparent density, (2) Water absorption, (3) Compressive strength, (4) Flexural strength, and (5) Abrasion resistance. This study proposes linear and exponential patterns for deterioration. A case study carried out on a Capernaum promenade revealed excessive deterioration patterns caused by the poor core properties of the paving stone and defective construction. The consequences of excessive deterioration on life cycle costs result in additional expenses of 73%, indicating a reduction in the life cycle. The novelty of this research lies in developing and delivering an integrated methodology that enables the assessment of how defective construction methods impact the durability, deterioration, life cycle, and life cycle costs of natural stone pedestrian pavements.

High Temperature Effects on Global Heritage Stone Resources: A Systematic Review

Throughout history, natural stone has been a crucial building material due to its strength, durability, and aesthetic qualities. Today, it continues to be a valuable resource, representing both a cultural heritage asset and a significant economic material. However, the increasing frequency of heat waves and fires driven by climate change poses a growing threat to stone building materials. This paper reviews the scientific attention given to the effects of high temperatures on Global Heritage Stone Resources (GHSRs), an international classification designed to enhance the recognition and status of building stones. Through a systematic SCOPUS search with refined filtering criteria, the study aims to quantify the existing research on these heritage stones. The search applied the standardized lithotype terms from GHSR publications to ensure consistency, followed by the exclusion of irrelevant terms when identified. Additionally, a relevance filter was applied to restrict the number of articles per lithotype and ensure that only the most pertinent studies were considered. Key findings from the literature reveal that exposure to high temperatures (ranging from 200 °C to 900 °C) significantly affected the studied GHSRs, leading to thermal micro-fissuring, increased porosity, and changes in water absorption, which compromise the mechanical properties of the stones. Moreover, these conditions can result in irreversible chemical transformations, exacerbating the deterioration of cultural heritage assets. The study emphasizes the critical need for research to better understand how these stone materials behave when exposed to high temperatures. It also provides a relevant framework for future investigations aimed at predicting and mitigating the effects of external threats such as fires.

Prediction of freeze–thaw and thermal shock weathering on natural stones through deep learning-based algorithms

Prediction of freeze–thaw and thermal shock weathering on natural stones through deep learning-based algorithms

An industrial robot-based sawing method for natural stone sculpture

Abstract In order to enhance the efficiency of stone sculpture machining while reducing natural stone waste and environmental pollution, a method for the efficient and green sawing of natural stone sculptures using industrial robots is proposed. The model contour is used as the directrix of the ruled surface to construct a ruled surface model that minimizes volume. The contour curve corresponding to this minimized-volume ruled surface model serves as the machining path for an integrated robotic diamond wire cutting system. A ruled surface model of Stanford Bunny was obtained by sawing a marble block using the robotic diamond wire cutting system. The experimental results show that the material removal rate of the robotic diamond wire cutting is 1.37 times that of saw blade cutting and 2.30 times that of grinding. The volume of stone powder generated during the processing was 0.16×10⁷mm³, accounting for only 1.47% of the total stone powder produced during the grinding process. In summary, the proposed method not only enhances processing efficiency but also reduces natural stone waste and mitigates environmental pollution.

Impact Assessment of Natural Stone Processing Techniques on the Grain Composition of Sludge Admixtures for Press Powder

Impact Assessment of Natural Stone Processing Techniques on the Grain Composition of Sludge Admixtures for Press Powder

Natural Stones Used in the Cultural Heritage of Latvia: Historical Context, Stone Selection Criteria, Durability, and Conservation

Natural Stones Used in the Cultural Heritage of Latvia: Historical Context, Stone Selection Criteria, Durability, and Conservation

Historical Quarry Landscapes of Three Finnish Granites

The quarry landscapes of Virolahti, Uusikaupunki, and Vehmaa are results of quarry operations during the most important periods of natural stone quarrying in Finland. The quarry landscape in Virolahti was formed in connection to the quarrying of red Virolahti pyterlite for the construction of St. Petersburg in Russia from the middle of 1700s to the beginning of the 1900s, while in Uusikaupunki, the quarry landscape is connected to the start of the modern Finnish stone industry and the National Romantic architecture at the beginning of the 1900s. The quarry landscape in Vehmaa is related to the start of the modern Finnish stone industry and export of Finnish granite at the beginning of the 1900s. In Virolahti, several small quarries can be seen, while in Vehmaa, a tendency towards fewer, but larger quarries start to emerge. In each area, human settlement was formed around the quarries. The geological basis for all areas is a rock type suitable for natural stone quarrying. The geotechnical features of each rock type indicate high resistance to wear and the products from these areas are early examples of durable construction. The quarry landscapes represent well the typical quarrying technology of the time and its development from channelling by chisels through hand drilling to mechanical drilling and blasting. The quarry areas form unique industrial and cultural heritage landscapes in Finland.

Petrological Characteristics and Physico-Mechanical Properties of Dokhan Volcanics for Decorative Stones and Building Material Applications

Wide varieties of igneous rocks are extensively utilized as stones for decoration purposes and as a potential source for building. With the use of petrological (mineralogical and chemical) and physico-mechanical analyses, the current work accurately mapped the Dokhan Volcanics (DV) and utilized them as decorative stones and their prospective in building materials using Frattini’s test. Field observations indicate that metavolcanics, DV, and monzogranites are the principal rock units exposed in the studied area. The DV rocks are characterized by a dense series of stratified, rhyolitic to andesitic lava interspersed with a few pyroclastics. Andesite, andesite porphyry, dacite, and rhyolite are the primary representatives of the selected DV. The lack of infrequent appearance of mafic units in the current volcanic eruptions indicates that the primary magma is not mantle-derived. This is supported by their Mg# (17.86–33.57). Additionally, the examined DV rocks have Y/Nb ratios above 1.2, suggesting a crustal source. The role of fractionation is interpreted by their variation from andesite passing through dacite to rhyolite, which is indicated by gradual negative distribution groups between silica and TiO2, Fe2O3, CaO, MgO, Co, and Cu from andesite to rhyolitic lava. Additionally, a wide range of widely used DV rocks like Y/Nb, Rb/Zr, and Ba/Nb point to crustal contamination in the rhyolitic rocks. The partial melting of the lower crust can produce andesitic magma, which ascend to higher crustal levels and form lava of calc-alkaline. A portion of this lava may split, settle at shallow crustal depths, and undergo differentiation to create the DV rocks. Based on the results of physico-mechanical properties, the studied samples met the requirements for natural stone to be used as decorative stones, whether as interior or exterior installations. The pozzolanic assessment of the studied rocks revealed their usability as supplementary cementitious materials in the building sector.

Radiation protection and natural building materials in cultural heritage

IntroductionBuildings that constitute cultural heritage and that are the identity of a defined geographical area are increasingly being restored to offer the community historical places to enjoy. Often the restoration preserves the original structure and building materials, which are usually natural stones. In this study, a radioprotection protocol dedicated to this kind of built environment was proposed and validated.MethodsAfter identifying the two predominant types of building material stones (Rosso ammonitico and Pietra Serena), radiometric measurements for natural gamma-emitting radionuclides (Ra-226, Th-232, and K-40) and measurements of the emanation coefficient and calculation of the exhalation rate of radon gas were carried out.ResultsThe two types of stone have a content of natural radionuclides that do not exceed the levels recommended by the regulations. The difference between the two types of stone is of an order of magnitude indicating that the red ammonite has a greater radiological impact than the pietra serena.DiscussionThe results, in addition to ensuring the radioprotection of the population, highlighted the need to increase the number of this kind of investigations to implement scientific knowledge and serve the stakeholders involved.

SELECTION OF MATERIALS TO CREATE A MATERIAL LIBRARY IN CARUARU-PE/BRAZIL: CASE STUDY OF ORNAMENTAL STONES

This study presents the first actions and steps towards creating a Material Library, which is related to the collection of ornamental, natural and synthetic stones. The work method was designed in three stages: 1. Analysis of communication problems perceived between the design and architecture areas in an ornamental stone transformation industry in the city of Caruaru - PE/Brazil; 2. Mapping of raw materials used by the company; 3. Systematization of data based on the mechanical properties and surface treatment of ornamental stones. As a result, a collection of more than 50 samples was catalogued, which will be used for the knowledge and daily use of the general population, for the learning of students, professionals and suppliers involved in the subject of material selection.

A Comparative Analysis of Time- and Condition-Based Approaches for Imperfect Maintenance of Natural Stone Claddings

A Comparative Analysis of Time- and Condition-Based Approaches for Imperfect Maintenance of Natural Stone Claddings

Noise and frequency propagation in natural stone processing plants

In this study, 510 noise measurements recorded in eight natural stone processing plants operating in Sivas City, Turkey were evaluated and the noise levels and dominant frequency bands of 11 different processing machines used in these plants were determined. The daily equivalent noise level of all natural stone processing plants was around or above the exposure limit value (87 dBA) specified in relevant regulations. Considering the machines and plant environment, the frequency ranges for the highest noise levels were mostly between 630 Hz - 5000 Hz, centering around 3150 Hz. Variations in the noise level of the processing machines in separate plants where similar processes were carried out was primarily related to the plant size and machine layout, the number of machines operating simultaneously and the type of natural stone processed. While the difference between the noise levels of gangsaws, bridge cutting, ST cutting, head/side cutting, trimming, cement filling, slab polishing, narrow polishing, chamfering and splitting machines were statistically significant, aging machines generated similar noise levels.

Experimental analysis of the bond-slip characteristics between CFRP and natural stone masonry units

Purpose Although the reinforcement of concrete and brick masonry with fiber-reinforced polymer (FRP) has been extensively researched, its application and impact on natural stone, especially in historic preservation, have received less attention. This study aims to examine the bond-slip characteristics of carbon fiber-reinforced polymer (CFRP) with two types of natural stone masonry, aiming to enhance their effectiveness in reinforcing historic structures. The stones studied include one from the Chouf-Lekdad region (A) and another from a historic structure in Sétif City (B). Both stones were strengthened using CFRP and carbon fiber fabric (CFF) through near-surface mount (NSM) and external bonding (EBR) techniques. Design/methodology/approach The interaction was assessed during the pull-out test by analyzing the stress transfer mechanisms, adhesion and deformation. This study also examines the effects of the following parameters on the bond between CFRP and stone: type of stone (A and B), type of reinforcement (plat CFRP and CFF), various notch shapes and sizes (bp, tp and Lb), and reinforcement techniques (NSM and EBR). Findings This study demonstrated the practicality and effectiveness of enhancing natural stone masonry of old buildings by integrating NSM and EBR techniques with CFRP. With a bond length of 30 mm, the pull-out force correlates with the strength of the stone. This indicates the importance of stone strength in obtaining better adhesion. The CFF–resin interface is more cohesive than the CFRP plate–resin interface because the resin penetrates the flexible CFF strip, ensuring better adhesion. In contrast, the CFRP plate interface is rigid and smooth. The results suggest that natural stone–CFRP adhesion is more effective than CFRP bonded to concrete and brick masonry due to the stone's strong resistance. Originality/value This experimental investigation provides new study into the bond-slip behavior of CFRP-reinforced natural stone masonry, filling the gap in existing research. The findings offer useful direction for creating FRP strengthening solutions that are specifically adapted to the properties of natural stone used in historic constructions. This study helps to improve preservation procedures by guiding the selection of reinforcing techniques, such as NSM versus EBR, and finding ideal bond lengths. This work's novelty stems from its ability to improve the structural integrity of culturally significant buildings while preserving their historical authenticity.

Superhydrophobicity, Photocatalytic Self-Cleaning and Biocidal Activity Combined in a Siloxane-ZnO Composite for the Protection of Limestone.

The erosion phenomena of the natural stone in cultural heritage are induced by various sources. Consequently, the development of multifunctional protective materials that combine two or more useful properties is an effective strategy in addressing the synergistic effects of various erosion mechanisms. A multifunctional coating, consisting of a silane-based precursor and zinc oxide (ZnO) nanoparticles (NPs), is produced and tested for the protection of limestone. The hybrid coating combines the following three properties: superhydrophobicity, including water-repellency, photocatalytic self-cleaning and biocidal activity. The relative concentration of the NPs (0.8% w/w), used for the suggested composite coating, is carefully selected according to wetting studies, colourimetric measurements and durability (tape peeling) tests. The non-wetting state is evidenced on the surface of the composite coating by the large contact angle of water drops (≈153°) and the small contact angle hysteresis (≈5°), which gives rise to a physical self-cleaning scenario (lotus effect). The photocatalytic chemical self-cleaning is shown with the removal of methylene blue, induced by UV-A radiation. Moreover, it is shown that the suggested coating hinders the incubation of E. coli and S. aureus, as the inhibitions are 94.8 and 99.9%, respectively. Finally, preliminary studies reveal the chemical stability of the suggested coating.

Waste From Alwar Quartzite (A Global Heritage Stone From Rajasthan - India) As Secondary Raw Materials for Cementitious Tile Adhesives

Waste deriving from quarrying operations of natural stone material retains almost all the mineralogical and compositional characteristics of the original material, for such reason this research aimed to test prototypes cementitious tile adhesives made up recycling the Alwar Quartzite waste, used as fine and ultra-fine aggregate. Particle size distribution analysis, along with X-ray diffractometry, X-ray fluorescence and Scanning Electron Microscopy were carried out to characterize the waste. Experimental research involved the mix-designing of three dough formulations (a regular one [N], a latex added [L] and a fast-setting [R]) tested by using different types of tiles: (i) polished metal plates, (ii) ceramic tiles and (iii) rough natural stone slabs. Fresh prepared doughs were firstly tested for thixotropy achieving high values (ranging 82–93%) and cured for normative requested time after being stuck on a concrete support as reported in European UNI standard regulations. After respective curing time, adhesives technical performances were evaluated by the Pull-Off test obtaining results for Class 1 (N and R) and Class 2 (L) adhesives with high initial tensile adhesive strength. Experimental results carried out in this research proved the possibility to use huge amounts of waste coming from Indian stone industry in cementitious tile adhesives sector without compromising technical performances, proposing itself as an alternative method to landfill disposal for this waste.

INVESTIGATION OF THE INFLUENCE OF CHOOSING THE TYPE OF FACADE SYSTEM USING ABC ANALYSIS ON THE COST OF THE LIFE CYCLE OF THE BUILDING OBJECT

The article is devoted to a comprehensive study of the influence of the choice of the type of facade systems on the total cost of the life cycle of the construction object, with a special emphasis on the application of ABC-analysis as a tool for determining the optimal option for arranging the facade, taking into account economic and quality aspects. The main purpose of the article is to justify the feasibility of using ABC analysis to select the type of facade systems and assess its impact on the costs associated with the life cycle of the building. The article provides a detailed analysis of various types of facade systems from the point of view of their fastening, materials, design and method implementation. Such systems as ventilated and non-ventilated facades, hinged ventilated facade systems, facades with cladding made of natural stone, composite materials and other modern materials are considered. Special attention is paid to the study of technological characteristics, durability and maintenance costs of various types of facade systems. The application of ABC analysis allows classifying facade systems according to their impact on the cost and quality of construction. In this context, facade systems are divided into three categories: A - the most important and expensive, B - medium importance and expensive, C - less important and with minimal expenses. This approach allows builders and designers to focus their attention on the most critical elements that affect the overall cost and efficiency of construction.As a result of the study, it becomes possible to make an informed decision regarding the choice of the optimal facade system, which best meets the specific needs of the project and contributes to the optimization of the cost of the life cycle of the building. In particular, the selection of appropriate materials and technologies allows to reduce construction costs, ensure durability and reduce maintenance and repair costs in the future. In addition, the results of the study can become the basis for the development of practical recommendations for professionals in the construction industry, including builders, designers and architects. This makes it possible to create more efficient, economical and ecologically sustainable construction objects. Also, the article emphasizes the importance of creating specialist training schools and conditions for the successful implementation of life cycle assessment technologies in the construction industry.

Analysis of Allocative Efficiency in Rice (Oryza sativa L.) Farming in the Batu Alam Industrial Area, Cirebon Regency

This research analyzes the efficiency of farming costs and the factors influencing rice farming costs. The research method used was descriptive quantitative with data collection techniques through surveys and interviews with 176 rice farmer respondents in the natural stone industrial area of Cirebon district. The analysis used is frontier cost analysis using frontier4.1 software using the Maximum Likelihood Estimation (MLE) approach. This research shows that the average cost efficiency or allocative level in the natural stone industrial area is 0.20. The factor that influences the inefficiency of rice farming in natural stone industrial areas is age. Factors directly influencing farming costs are land area, urea, labor, rice selling price, land rental price, and labor wages.

Investigating the Role of Microclimate and Microorganisms in the Deterioration of Stone Heritage: The Case of Rupestrian Church from Jac, Romania

Natural stone can undergo disaggregation from various causes, including physical actions such as freeze–thaw cycles, temperature and humidity variations, chemical actions such as the solubilization of minerals by organic and inorganic acids, as well as biological actions due to the colonization of organisms that can produce biocorrosion and biomineralization. This research investigates the impact of microclimatic conditions and microbial activity on the physical and chemical integrity of stone heritage, particularly the biodeterioration caused by fungi in the case of a Romanian rock church. Various analytical techniques were employed, including macroscopic and optical microscopy, Raman spectroscopy, X-ray diffraction, and culture-based identification methods, to characterize the mineral composition and microbial contamination of the rock samples. The analyses revealed that the sandstone consists primarily of quartz (over 90%), muscovite (5–10%), and feldspars. The identified fungi included Cladosporium herbarium, Aspergillus niger, and Mortierella hyalina. The SEM images showed fungal hyphae and spores within the kaolinite–illite matrix, indicating significant microbial colonization and its role in rock deterioration. Additionally, microclimatic data collected over a 12-week period highlighted the substantial fluctuations in temperature and relative humidity within the church, which contribute to the physical and chemical weathering of the stone. This study also noted high levels of particulate matter (PM2.5 and PM10) and volatile organic compounds, which can exacerbate microbial growth and stone decay. The comprehensive analysis underscores the need for targeted preservation strategies that consider both microclimatic factors and microbial colonization to effectively conserve stone heritage sites, ensuring their longevity and structural integrity.