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This study investigates the influence of density and bubble distribution on the performance of emulsion explosives through physical sensitization by incorporating expanded perlite (5%–25%) to adjust density. The detonation velocity was measured using a continuous velocity meter. The results demonstrate that as the perlite content increases, the density of the emulsion explosives decreases, while the detonation velocity exhibits a nonlinear trend of initial increase followed by a decline. The maximum detonation velocity of 4713 m/s was achieved at 10% perlite content. However, when the content reached 25%, the explosive became completely desensitized, with a detonation velocity of 0. These findings provide a theoretical basis for addressing misfire issues in emulsion explosives by directly modifying density and optimizing bubble distribution.

Currently, chimney technology is looking for new materials with improved thermal insulation properties and, at the same time, adequate durability. The use of concretes based on lightweight aggregates, such as expanded perlite, is capable of meeting such a challenge, provided that the composition of the concrete mixes is appropriately modified. The main research challenge when designing chimney system casing elements lies in ensuring adequate resistance to moisture penetration (maximum water absorption of 25%), while achieving the lowest possible bulk density (below 1000 kg/m3), sufficient compressive strength (minimum 3.5 MPa), and capillary water uptake not exceeding 0.6%. In the present research, laboratory tests were conducted to improve the fundamental technical properties of lightweight perlite-based concrete to meet the aforementioned requirements. Laboratory tests of perlite concrete were carried out by adding eight chemical admixtures with a hydrophobic effect and the obtained results were compared with a reference concrete (without admixtures). However, the positive results obtained under laboratory conditions were not confirmed under actual production conditions. Therefore, further tests were conducted on chimney casings taken directly from the production line. Subsequent chemical admixtures with a hydrophobic effect, based on silane/siloxane water emulsions, were applied to determine the concrete mix’s optimal composition. The results of the tests carried out on perlite concrete chimney casings from the production line confirm the effectiveness of the applied chemical admixtures with a hydrophobic effect in improving the moisture resistance. This was further supported by the outcomes of the so-called ‘drop test’ and capillary uptake test, with the suitable bulk density and compressive strength being maintained.

The objectives of this study include minimizing the thermal conductivity of the produced materials, reducing dead loads of structures through lightweight composite material production, and increasing perlite use in areas close to material deposits. To this end, lightweight geopolymer composites were produced using ground raw perlite as a precursor, expanded perlite as an aggregate, and sodium hydroxide (NaOH) as an activator. The produced samples were cured in an oven at 110 °C for 24 h. Within the scope of this study, unit weight, compressive strength, and thermal conductivity coefficient tests were conducted. Additionally, microstructure analysis was carried out using scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP). As a result, it has been shown that ground raw perlite can be used as a precursor in geopolymer composites, while expanded perlite demonstrates suitability as a lightweight and porous aggregate for heat insulation applications.

Nowadays, much of the attention paid to building construction is focused on sustainability and environmental protection. The materials applied in construction should be safe and free of toxins, but they should also follow the idea of circular construction. Quests for materials with an appropriate structure and composition, unifying features of a construction, insulation (thermally and acoustically), and environmentally friendly material turned our attention in this paper toward expanded perlite (EP). This study aimed to analyze the results of the experimental determination of the basic physical and mechanical parameters of expanded perlite and pure perlite concrete blocks (PPC), i.e., containing 100% EP instead of sand, while in contrast, most existing studies focus only on the partial replacement of sand with EP. This research aims to confirm that PPC containing 100% EP is the product that meets the requirements for load-bearing walls in single-family buildings in European countries such as Poland. The study aimed to determine the procedure for preparing the samples of PPC, i.e., the mixing procedure, the displacement speed during compaction, and the maximum loading force during compaction. It was determined that the appropriate speed of compaction to form the samples is 15 mm per minute, i.e., the same as during the compressive strength tests. The maximum compaction force of 10,000 N during the preparation of samples at a speed of displacement of 15 mm per minute guarantees a compressive strength greater than 3 MPa for dry density class 650, and the method of forming the samples in a single layer, i.e., solid samples.

These days, the use of natural materials is required for sustainable and consequently plus-, zero- and low-energy construction. One of the main objectives of this research was to demonstrate that pelite concrete block masonry can be a structural and thermal insulation material. In order to determine the actual thermal insulation parameters of the building partition, in situ experimental research was carried out in real conditions, taking into account the temperature distribution at different heights of the partition. Empirical measurements were made at five designated heights of the partition with temperature and humidity parameters varying over time. The described experiment was intended to verify the technical parameters of perlite concrete in terms of its thermal insulation properties as a construction material used for vertical partitions. It was shown on the basis of the results obtained that the masonry made of perlite concrete blocks with dimensions of 24 × 24.5 × 37.5 cm laid on the mounting foam can be treated as a building element that meets both the structural and thermal insulation requirements of vertical single-layer partitions. However, it is important for the material to work in a dry environment, since, as shown, a wet perlite block has twice the thermal conductivity coefficient. The results of the measurements were confirmed, for they were known from the physics of buildings, the general principles of the formation of heat and the moisture flow in the analysed masonry of a perlite block. Illustrating this regularity is shown from the course of temperature and moisture in the walls. The proposed new building material is an alternative to walls with a layer of thermal insulation made of materials such as polystyrene or wool and fits into the concept of sustainable construction, acting against climate change, reducing building operating costs, improving living and working conditions as well as fulfilling international obligations regarding environmental goals.

This study presents an innovative heterogeneous nanocatalytic system designed through a multistep synthetic approach involving the surface functionalization of perlite nanoparticles (Perlite NPs/Met‐Co(II)). Comprehensive characterization using fourier transform infrared spectroscopy (FTIR), X‐ray diffraction, field‐emission scanning electron microscopy, energy‐dispersive X‐ray analysis (EDX), elemental mapping, thermogravimetric analysis, and brunauer‐emmett‐teller (BET) analyses confirms the successful formation of a hierarchically structured catalyst. The catalyst enables efficient one‐pot multicomponent synthesis of pyrazolopyranopyrimidines in water (100 °C, 5 mg loading), yielding 87–95% in 30–60 min. The presented method adhering to green principles and also recyclability (6 cycles) and synergistic performance provides an atom‐economic platform for sustainable heterocycle synthesis. This study presents an innovative heterogeneous nanocatalytic system based on perlite nanoparticles (Perlite NPs/Met‐Co(II)). Comprehensive characterization using FTIR, XRD, field‐emission scanning electron microscopy, EDX, elemental mapping, TGA, and BET analyses confirms the hierarchically structure of nanocatalyst. The catalyst enables green and efficient one‐pot multicomponent synthesis of pyrazolopyranopyrimidines in water adhering to green principles.

To enhance the insulation performance, strength, and fire resistance performance of foamed concrete, this paper investigates the effects of incorporating nano-silica aerogel and expanded perlite. A comprehensive comparison and analysis were conducted on the dry density, water absorption, mechanical performance, thermal conductivity, fire-resistant insulation, and microstructure of both Nano-SiO 2 Aerogel Foamed Concrete (NSAFC) and Expanded Perlite Foamed Concrete (EPFC). The findings indicate that as the Nano-SiO 2 Aerogel (NSA) content increases, the water absorption of the foamed concrete gradually rises. Conversely, the water absorption of the foamed concrete test blocks first increases and then decreases with an increase in Expanded Perlite (EP) content. It is noteworthy that, incorporating 10% NSA and EP reduces the dry density of foamed concrete by 12.7% and 7.8%, respectively. When EP content reaches 6%, the 28-d flexural and compressive strengths of the foamed concrete test blocks increase by 73.5% and 54.2%, respectively. Similarly, at NSA content of 6%, the 28-d flexural and compressive strengths increase by 70.5% and 39.6%, respectively. The fire-resistant insulation tests demonstrate that NSAFC exhibits superior thermal insulation and fire resistance performance compared to EPFC. Furthermore, SEM images demonstrate that the pore structure of NSAFC is more uniform.

Clay soils, particularly kaolinite, often exhibit low strength and high deformation, necessitating stabilization for geotechnical applications. This study investigates the potential of calcium carbide residue (CCR) and its partial substitution with perlite powder (PP) and water treatment sludge (WTS) to enhance the strength and microstructure of kaolinite clay. To capture both mechanical response and structural evolution, unconfined compressive strength (UCS) and ultrasonic pulse velocity (UPV) tests were conducted at 7, 28, and 56 days of curing. The microstructural changes were also investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) analyses to reveal cementitious gel formation. The findings show that the addition of 4% CCR increased UCS by about 10 times to 1395 kPa, while partial replacement with 25% PP and 10% WTS further enhanced UCS by nearly 14 times, reaching 1783 and 1744 kPa, respectively. Similarly, UPV increased from approximately 280 m/s in untreated clay to over 1500 m/s in stabilized blends, indicating a denser and more cohesive microstructure. The results of secant modulus (E 50 ) and energy absorption capacity (E u ) followed the same trend as UCS. Partial replacement of CCR with 25% PP led to the highest long-term improvements, producing E 50 of 1021 MPa and E u of 535 kJ/m 3 , while substitution with 10% WTS also yielded substantial gains, reaching an E 50  of 1011 MPa and an E u of 520 kJ/m 3 . These enhancements corresponded to increases of up to 18 times and 9 times over untreated soil, confirming greater stiffness but a shift toward more brittle behavior. Microstructural analysis revealed the formation of tightly bonded cementitious gels and superior particle packing, which directly account for the pronounced improvements in the strength and stiffness of the stabilized samples. Overall, the results demonstrate that CCR, particularly when partially substituted with PP or WTS, presents a strong potential as a sustainable alternative to conventional cement-based stabilizers, offering significant improvement in soil performance along with environmental benefits.

This study compares the workability, mechanical, and thermal characteristics of structural self-compacting lightweight concrete (SCLWC) formulations using pumice aggregate (PA), expanded perlite aggregate (EPA), fly ash (FA), and silica fume (SF). FA and SF were used as partial substitutes for cement at a 10% ratio in various mixes, impacting different aspects: According to the obtained results, FA enhanced the workability but SF reduced it, while SF improved the compressive and splitting tensile strengths more than FA. EPA, used as a fine aggregate alongside PA, decreased the workability, compressive strength, and splitting tensile strength compared to the control mix (K0). The thermal properties were altered by FA and SF similarly, while EPA notably reduced the thermal conductivity coefficients. The thermal conductivity coefficients (TCCs) of the K0–K4 SCLWC mixtures ranged from 0.275 to 0.364 W/mK. K0 had a TCC of 0.364 W/mK. With 10% FA, K1 achieved 0.305 W/mK; K2 with 10% SF reached 0.325 W/mK. K3 and K4, using EPA instead of PA, showed significantly lower TCC values: 0.275 W/mK and 0.289 W/mK, respectively. FA and SF improved the thermal conductivity compared to K0, while EPA further reduced the TCC values in K3 and K4 compared to K1 and K2. The compressive strength (CS) values of the K0–K4 SCLWC mixtures at 7 and 28 days reveal notable trends. Using 10% FA in K1 decreased the CS at both 7 days (12.16 MPa) and 28 days (22.36 MPa), attributed to FA’s gradual pozzolanic activity. Conversely, K2 with SF showed increased CS at 7 days (17.88 MPa) and 28 days (29.89 MPa) due to SF’s rapid pozzolanic activity. Incorporating EPA into K3 and K4 reduced the CS values compared to PA, indicating EPA’s lower strength contribution due to its porous structure.

A laboratory investigation was conducted to evaluate the structural behavior of ferrocement composite panels (FCPs) incorporating expanded perlite lightweight aggregate (LWA) at varying volume fractions (55%, 35%, and 15%). Twelve lightweight FCPs (60 × 60 × 4 cm) were fabricated with one, two, or three layers of expanded rib lath and tested under three-point flexural loading. Structural response was assessed using digital image correlation (DIC) and theoretical analysis based on the thin plate theory. The results showed that increasing the number of rib lath layers significantly enhanced the first crack load (F cr ) and ultimate load (F u ), with improvements ranging from 11 to 224% in F cr and 18 to 76% in F u . Deflection at first crack ( ) and ultimate load ( ) increased by an average of 47% and 229%, respectively. Additionally, the use of perlite LWA increased and by 29% and 26% compared to regular FCPs, highlighting its effectiveness in enhancing flexibility. DIC analysis identified transverse strain (ε xx ) as the most sensitive parameter for early crack detection. Taguchi optimization further revealed that the number of rib lath layers had a more significant impact on F cr and F u than perlite content. These findings suggest that a three-layer FCP system with 15% perlite replacement optimizes load-bearing capacity, making it well-suited for high-strength, lightweight applications such as modular buildings and prefabricated structural elements.