Search Results (28)

The polished stone value (PSV) is a key parameter for assessing the resistance of aggregates to polishing in the laboratory. It is included in technical specifications and serves as both a regulatory and contractual criterion for selecting aggregates for wearing courses. Its determination requires non-negligible amounts of material, long testing durations, and skilled operators. This study aims to develop a predictive modeling approach to estimate the polished stone value (PSV) from the mineralogical and chemical composition of aggregates. A curated database was compiled from the peer-reviewed literature, and compositional data were transformed using Isometric Log-Ratio (ILR) to generate physically interpretable balances and avoid constant-sum artifacts. Machine learning algorithms, including Gradient Boosting, CatBoost, and Multivariate Adaptive Regression Splines (MARS), were trained and evaluated using repeated 10 × 2 K-Fold cross-validation with preprocessing embedded within the loop. CatBoost achieved the highest accuracy, with 90.4% of predictions within ±20% of the measured PSV. Model interpretability using permutation feature importance and SHAP analysis identified meaningful drivers, highlighting the roles of CO₂/SO₃ versus the major-oxide framework, and silica-rich oxides versus CaO/MgO, consistent with petrographic expectations. The proposed workflow provides a practical and interpretable approach for predicting PSV from compositional data. It offers a time- and resource-efficient alternative to conventional laboratory tests, while also providing insight into the material factors that control aggregate polishing resistance. Limitations related to dataset size and inter-source variability are discussed. Full article

This study investigates the synergistic use of Fischer–Tropsch wax (FTW) and recycled rubber powder (RP) as dual modifiers in stone mastic asphalt (SMA11) to improve its mechanical and functional performance. Rheological analysis demonstrated that an FTW content of 4% achieves the optimal balance of high-temperature rutting resistance, aging resistance, and workability, with a binder viscosity of 1.6 Pa·s at 135 °C. When incorporated into SMA11 mixtures at 15%, RP yielded the best overall mechanical performance, including a reduction in rut depth to 1.22 mm and a 25% decrease in wheel tracking slope (WTS). The 15% RP mixtures also exhibited superior long-term skid resistance (μ_m = 0.329 after 180,000 polishing cycles, corresponding to a 13% reduction in braking distance) and enhanced thermal cracking resistance (failure temperature improved by 8.0 °C to −32.7 °C). An RP content of 5% maximized moisture resistance (ITSR = 100%), while 10% RP produced the highest mid-frequency sound absorption coefficient (α = 0.050). The hybrid modification system enables a 20 °C reduction in production temperature, consistent with published data on wax-based warm-mix technologies, and is associated with reduced energy consumption and lower emissions. The approach simultaneously supports sustainable pavement design through the high-value reuse of waste tire rubber. Full article

This paper presents an innovative concept for the musealization of everyday public space through the use of natural stone cladding as an in situ palaeontological exhibition. Polished slabs of Holy Cross Mts marble, widely used as flooring in public buildings, contain abundant and well-preserved Devonian marine fossils, offering a unique opportunity to revitalize public engagement with palaeontology and geoheritage. The proposed exhibition transforms passers-by into active observers by integrating authentic fossil material directly into daily circulation routes, thereby emphasizing the educational and geotouristic potential of ordinary architectural elements. The case study focuses on the main hall of the University of the National Education Commission (Kraków, Poland), where over 1000 m² of fossil-bearing limestone flooring is used as a continuous exhibition surface. The target audience includes students of Earth sciences, zoology, biological sciences, pedagogy, social sciences, and humanities, for whom the exhibition serves as both an educational supplement and a geotouristic experience. The scientific, educational, and touristic value of the proposed exhibition was assessed using a modified geoheritage valorization method and compared with established palaeontological collections in Kraków and Kielce. The expert valuation method used in the article enables a comparison of the described collection with other similar places on Earth, making its application universal and global. The results demonstrate that polished stone cladding can function as a valuable geoheritage asset of regional and global significance, offering an accessible, low-cost, and sustainable model for disseminating palaeontological knowledge within public space. Full article

Background/Objectives: Silicosis caused by dust from engineered stone (ES) exposure is an emerging occupational lung disease that severely impacts respiratory health. This study aimed to analyze the association between cytokine profiles and disease severity and progression in patients with engineered stone silicosis (ESS) to assess their potential as biomarkers of progression and their usefulness to stratify risk. Methods: A longitudinal study was conducted with a seven-year follow-up (2017-2024) on 72 workers with simple silicosis (SS) or progressive massive fibrosis (PMF), all with a history of cutting, polishing, and finishing ES countertops. Data on lung function and levels of 27 cytokines were collected at four control points. Machine learning (ML) models were built to classify the disease stage and predict its progression. Results: 39% of patients with SS progressed to PMF. Significant differences in the expression of some cytokines were observed between ESS stages, suggesting a role in the evolution of the inflammatory process. Specifically, higher levels of IL-1RA, IL-8, IL-9, and IFN-$\gamma$ were found at checkpoint 1 in patients with PMF compared to SS. The longitudinal analysis revealed a significant relationship between IL-1RA and MCP-1$\alpha$ and disease duration with MCP-1$\alpha$ also being associated with time and disease grade. Machine learning (ML) models were built using the cytokines selected through a sequential backward feature selection. The Support Vector Machine model achieved an accuracy of 83% in classifying disease stage (SS, PMF), and of 77% in predicting the disease progression. Conclusions: The findings suggest that cytokines can be used as dynamic biomarkers to reflect underlying inflammatory processes and monitor disease evolution. The performance of ML algorithms to predict diagnostic status based on cytokine profiles highlights their clinical value in supporting early diagnosis, monitoring disease progression, and guiding clinical decisions. Full article

Despite local and national road authorities striving to provide motorists with a durable and safe infrastructure environment, one in six UK roads are currently classed as being in poor condition. In terms of safety, Department for Transport statistics report high numbers of road incidents; 29,711 killed or seriously injured in 2023, representing little change compared to 2022. As such, reported in this paper is research aimed at developing artificial geopolymer cement mortar-based aggregate as a cost/environmentally attractive alternative to calcined bauxite for high friction surfacing applications. Work was undertaken in two distinct phases. In the first, the performance of alkali silicate-based geopolymers comprising a range of industrial wastes as binder materials was assessed using modified versions of standardized polished stone value and micro-Deval tests. In phase two, selected mixes were assessed for resistance to simulated wear by exposing test specimens to 20,000-wheel passes on an accelerated road test machine. Performance was further investigated using a dynamic friction test method developed by the Indiana Department of Transportation. Despite commercially sourced calcined bauxite aggregates exhibiting the highest performance levels, the findings from this preliminary research were generally positive, with acceptable levels of performance noted for manufactured geopolymer-based aggregates. For instance, in accordance with recommended levels of performance prescribed in BBA/HAPPAS standards, this included attainment of polished stone values higher than 65 and, following accelerated road testing, average texture depths greater than 1.1 mm. It is recognized that further research is needed to investigate geopolymer binder systems and blends of aggregate types, as well as artificial aggregate manufacturing procedures. Full article

The rationale for this work arose from the urgency of improving the energy efficiency of buildings at the design stage, given the changing requirements of energy efficiency standards such as the Polish Technical Conditions (WT 2014 and WT 2020). This research is novel as there is currently limited information available on the improvement of the thermal performance of ventilated stone facade systems, although they are now widely used due to their practical and aesthetic advantages. The first objective of this work is to evaluate the thermal performance of the ventilated facades of the Praski Student House (Akademik Praski) and to assess how certain design variations can help achieve a lower level of energy consumption. Using a comprehensive case study approach, this study provides accurate thermal calculations of the facade to assess its global thermal insulation coefficient (Rt) and thermal transmittance (Uc). The improvement in the actual U-value from the original design is as follows: the U-value is reduced from 0.33 originally to 0.228 for WT 2014 and to 0.198 for WT 2020, showing a reduction of about 30.9% and 13.2%, respectively. These results indicate the energy efficiency of increased insulation thickness and optimally oriented air gap dimensions. The practical contributions of this research are valuable for architects, engineers, and contractors involved in the design and construction process of buildings aiming to achieve near-zero energy buildings (nZEBs), including concrete suggestions on how to improve current construction practices as well as material recommendations. There is a need for durability studies, for example to assess the performance of such facades under different climatic conditions, as part of future work to support these findings. Full article

Inefficiency and poor quality are the main problems in polishing natural heterogeneous marbles using sol-gel (SG) diamond pads. A strategy was proposed to address these issues by establishing a natural heterogeneous marble polishing model based on the optimal polishing time. The surface evolution and optimal time for polishing natural heterogeneous marble were systematically investigated. Six different types of marbles were polished by the sol-gel diamond pads. The surface glossiness, roughness, peak–valley value, and surface morphology of the marbles were measured and analyzed after different polishing times. The optimal polishing time for each marble was revealed using sol-gel diamond pads. The experimental results show that the standard deviation of the hardness distribution of marble tile significantly affects the material removal inconsistency and evolution of the surface during polishing, resulting in different optimal polishing times for different kinds of marble. The larger the standard deviation of the hardness of the marble is, the more difficult it is to obtain better surface quality, and the orange peel effect is more likely to occur. Furthermore, the optimal polishing time has a good logarithmic relationship with the standard deviation of the hardness distribution. Finally, a curve model of the optimal polishing time for each marble was established. The determination of the optimal polishing time can effectively optimize the polishing process, simplify the processing flow, improve production efficiency, and reduce production costs. The proposed method and obtained results in this paper can provide a theoretical basis and reference for polishing other types of heterogeneous stone materials. Full article

Esthetically pleasing temporary prostheses are often necessary for extended periods in a variety of clinical scenarios. Adjustments to the occlusion or margins are commonly needed before cementing the temporary prosthesis. Therefore, it is clinically necessary to repolish the rough surface to avoid biological and esthetic issues associated with rough surfaces. The purpose of this in vitro study was to assess and compare the impact of various polishing protocols on the surface roughness and color stability of three resin materials used for provisional crowns. A total of 150 specimens were fabricated from auto-polymerizing polymethyl methacrylate, bis-acryl composite, and Methyl methacrylate-LC resin using a stainless steel mold. Each material group was divided into five groups (n = 10) based on the applied surface treatment: positive control group (G1): no roughening or surface treatment, Negative control group (G2): acrylic bur-roughened surface without any polishing, the different surface treatment groups of silicon carbide and aluminum oxide stone polishing (G3), diamond-coated rubber twist (G4), and Surface Glaze (G5). An optical profilometer was used to assess the surface roughness of all samples. After undergoing 6000 cycles of thermocycling followed by immersion in a coffee solution for 15 days at 37 °C, color parameters were measured using a spectrophotometer both before and after a storage period to evaluate color differences. A two-way ANOVA test with α = 0.05 significance level was carried out to determine the impacts of both the materials utilized and the polishing protocol. Among the three types of resin examined, the bisacryl group exhibited superior surface quality in positive control groups, while PMMA resin demonstrated higher polishability. The diamond-coated rubber twits resulted in lower Ra values of 0.36 (0.01) µm, 0.52 (0.11) µm, and 0.28 (0.05) µm for PMMA, BAMA, and MMLC resins, respectively. The application of photo-polymerized surface glaze led to a plaque accumulation threshold of 0.2 µm across all resin groups. The greatest mean color change occurred in the negative control group, indicating a propensity for more staining on rougher surfaces. The Bisacryl resin exhibited higher ΔE values, whereas PMMA showed better color stability. The lowest ΔE values were found when the surface glaze was applied to all of the provisional crown resins. Untreated Bisacryl resin exhibited the lowest Ra values, while PMMA resins demonstrated superior surface morphology after polishing. PMMA provisional crown resins showed increased resistance to staining. The use of surface glaze enhanced both smoothness and color stability on the surfaces. Full article

The utilization of dimension stone in construction has been prevalent since ancient times; however, its application in modern construction has gained significant attention over the last few decades. This research aimed to assess the physical and strength properties of volcanic rocks from the Kohistan Island Arc for their potential use as dimension stone. Five types of andesites (MMA, PMA-1, PMA-2, CMA, and FMA) and two types of agglomerates (AG-1 and AG-2) were identified based on their composition, color, and texture. The samples were characterized in terms of their petrography (compositional and textural), physical properties (specific gravity, water absorption, and porosity), and strength properties (unconfined compressive strength and unconfined tensile strength). Two non-destructive tests (ultrasonic pulse velocity test and Schmidt hammer) were conducted, and the degree of polishing was evaluated. Correlation analyses were carried out to establish possible relationships among these parameters. The presence of chlorite, epidote, sericite, and recrystallized quartz indicated signs of low-grade metamorphism in andesites. The study revealed that feldspar, amphibole, and quartz imparted good physical and strength properties to samples MMA, CMA, FMA, AG1, and AG2. On the other hand, PMA-1 and PMA-2 exhibited reduced physical and strength properties due to the abundance of alteration products like chlorite, sericite, and epidote. The unconfined compressive strength exhibited a strong correlation with ultrasonic pulse velocity, skeletal density, porosity, and water absorption. Weathering grade considerably affected the values of ultrasonic pulse velocity and Schmidt hammer. Consequently, samples PMA-1 and PMA-2 are not recommended for load-bearing masonry units and outdoor applications due to their high water absorption and low strength values. On the other hand, samples FMA and MMA exhibited excellent properties like high strength and good polishing, indicating their potential use as decorative and facing stones, external pavement, ashlar, rubbles, and load-bearing masonry units. Full article

The long-term endurance of building stones must be assured since their longevity has repercussions for their economic and social value. Frequently, slabs for flooring and cladding are installed with polished finishing in outdoor environments for technical and ornamental purposes in cultural heritage sites and modern civil architecture. Compared to any other finishing, glossy surfaces are rather vulnerable to wear, particularly when they interact with slightly acidic rainwater. Several hydrophobic treatments are applied to prevent this damage by preventing contact between rain and stone; such treatments are efficient but sometimes non-durable. Stakeholders and conservation scientists need better methods to anticipate the future behaviour of this building material and hydrophobic solutions. Complying with this demand, a comparison is made between outdoor natural ageing and artificial weathering, reproduced by UVA radiation, moisture and spray accelerated weathering. Artificial weathering is applied to predict the behaviour of stones over time in the real environment. Data obtained through the measurement of gloss and colour parameters, the detection of micro-textures through SEM, and the calculation of micro-roughness using a digital rugosimeter demonstrate that weakly acidic rainwater is the main cause of superficial decay of stone finishing over just six months of outdoor exposure. This period corresponds to 7–14 days of artificial weathering. Furthermore, the loss of efficiency and durability of the hydrophobic coatings is detected by measuring the static contact angle. This highlights that even if a protective treatment was proficient, it could easily deteriorate in normal weathering conditions if applied on polished, low-porosity stone. Additionally, water vapour permeability indicates variations of regular vapour transmission through the stones due to ageing. The first solution to threats is the prevention of pathologies, including aesthetic ones. A careful choice of the most suitable lithotype finish and an environmental study represent an existing solution to the problem. It must be highlighted that aesthetic requirements should not be prioritised to detriment of the technical requirements of architectural quality, performance, durability, and safety. Full article

This study intends to predict the long-term skid resistance of steel slag asphalt mixture (SSAM) from the mineral composition of the aggregates. The polished stone value (PSV) and mineral composition of the aggregates were assessed using the accelerated polishing test and X-ray diffraction, respectively. The hardness (H) and surface texture richness (STR) of the aggregates were calculated from the mineral composition of the aggregates, and then a multivariate linear model was established between PSV and H and STR. The British pendulum number (BPN) and three-dimensional morphology of the SSAM were then evaluated using a British pendulum and a pavement laser scanner, respectively. Finally, an exponential relationship was established between BPN, aggregate PSV, and various aggregate amounts of SSAM. The results show that steel slag with H, STR, and PSV was better than natural aggregates and can significantly improve the skid resistance of pavement, but the relationship between steel slag content and long-term skid resistance of SSAM was not linear, and SSAM with 50% steel slag content had the best skid resistance. The mathematical model developed can predict the long-term skid resistance of SSAM from the mineral composition of the aggregates. The model can be used by designers to predict the long-term skid resistance of steel slag asphalt pavements at the design stage and thus better determine the proportion of steel slag to other aggregates. Full article

The widespread use of natural aggregates is one of the main causes of the depletion of natural resources, as aggregates are constituents of several construction materials. Alternatively, it is, today, proven to be feasible to use mining tailings, either natural or recycled materials, to produce artificial aggregates through specific processes. A possible way to produce artificial aggregate is through the alkali activation of the powdered material in a process called geopolymerization. This study proposes to use a basalt powder and two different metakaolins as precursors for the production of an alkali-activated artificial aggregate, with a specific shape and size achieved by using 3D-printed molds. The experimental aggregates were evaluated using traditional tests for natural aggregates, such as resistance to compression, specific density and resistance to abrasion and fragmentation. Furthermore, the material was chemically analyzed in order to evaluate the geopolymerization process promoted by the two adopted metakaolins. The physical tests showed that artificial aggregates do not perform well in terms of resistance to wear and fragmentation, which can be improved. However, they revealed promising results in terms of skid, polishing and micro-texture. Full article

Operating parameters affect the wear of abrasive tools during the polishing stage in building stone processing plants. This study investigates the effects of essential operating parameters including polishing head pressure, head rotation speed and water flow rate on the wear of the abrasive tools. For this purpose, a building stone abrasivity test was used to determine the weight loss of the abrasive tools during laboratory polishing of fifteen different types of Iranian granitic building stones. The standard operating parameters of the test were a polishing head pressure of 5 bar, a head rotation speed of 300 revolutions per minute (rpm), and a water flow rate of 4 L/min. The values of the operating parameters were changed to values within the range from ±25% and ±50% of the standard conditions in order to investigate the effect of variations in these parameters on the wear of the abrasive tools during the polishing stage. The results of different tests showed that the wear of the abrasive tools was directly proportional to the pressure up until a critical value of around 6.25 bar, after which it gradually decreased. This nonlinear wear behavior does not conform to Archard’s well-known classical wear law. The FESEM images of the worn surfaces showed that due to excessive load, debonded abrasive particles could not be pulled out from the pin surface and led to an interlocking phenomenon between the pin and stone surface. It was also found that the wear of the abrasive tools increased with increasing head rotation speed, while it decreased with the water flow rate. Moreover, the main wear mechanism of tests was abrasive wear and in some cases with a mixture mode of adhesion and delamination. Full article

Natural stones are a widely used construction material for both structural and decorative purposes. It is a material used for many floors and cladding due to its special beauty and quite aesthetic appearance. However, natural stones are exposed to different temperatures due to natural, urban or industrial activities and they lose their physico-mechanical properties. It is known that high temperatures and fire cause degradation of construction and building stones. There are many studies investigating the effect of high temperatures on physical and mechanical properties of natural stones, while there are very limited studies on color and gloss. In this study, the changing physical and mechanical properties, color and gloss of different light-colored polished natural stones exposed to room temperature up to 1000 °C in the oven were investigated. For this purpose, natural stones were gradually exposed to 200, 400, 600, 800 and 1000 °C, starting from room temperature. After exposure to different temperatures, water absorption, porosity, Schmidt hammer hardness, point load strength, color and gloss were measured and compared to reference samples (at room temperature). However, all samples were decayed at 1000 °C, changes at this temperature value could not be determined. The results obtained at other temperature values were evaluated separately for each parameter. While the change in physico-mechanical properties of all samples up to 400 °C was limited, a dramatic change was observed with increasing temperature. In all samples, point load strength losses were observed due to an increase in porosity and water absorption. In addition, all samples darkened at 400 °C, while the whiteness value (L*) of samples increased at 800 °C. Gloss values gradually decreased due to the increase in temperature. Full article

The skid resistance of asphalt pavement is of great importance to the driving safety, but deterioration of pavement skid resistance is inevitable owing to the coupling effect of traffic loading and climate conditions. The existing prediction models of skid resistance were mainly established based on the laboratory accelerated polishing tests (for instance Polished Stone Value, PSV), and these models can only consider the influence of a single factor; they fail to reflect the coupling effect of different factors under the real service condition. For the purpose of investigating the influences of seasonal variation, and aggregate type on the skid resistance of asphalt pavement, the skid resistance of three test tracks were continuously measured for 48 months through five different test methods. The results show that different test methods exhibit significant inconsistency. The aggregate type is the internal factor that determines the long-term skid resistance performance of pavement. The skid resistances of the selected test tracks were ranked as greywacke pavement > diabase pavement > rhyolite pavement. This is in well agreement with the ranking of aggregate polishing resistance obtained from the laboratory Wehner/Schulze (W/S) test. This indicates that the W/S test is effective in distinguishing the aggregates that used in pavement construction. It is also found that the skid resistance of asphalt pavement shows significant fluctuation with respect to seasonal variation. The skid resistance is generally high in autumn and low in summer. Therefore, it is suggested to use the low measurement value of skid resistance in summer as the lower limit for the evaluation and prediction of the skid resistance performance of asphalt pavement. Full article