Flexural Strength Research Articles

Effect of nano-TiO2 size and utilization ratio on the performance of photocatalytic concretes; self-cleaning, fresh, and hardened state properties.

In this study, photocatalysis technology was used to reduce water pollution. Decolorization of Reactive Black 5 using nano-TiO2 (NT) as a photocatalyst was investigated by adsorption and degradation experiments. Effects of NT particle size and utilization ratio on the time-dependent flow performance, compressive-flexural strength, and Bohme abrasion resistance of cementitious systems were investigated. In addition to the NT-free control mixture, a total of six photocatalytic self-cleaning mortar mixtures (PSCM) were prepared using NT in two different particle sizes (28 and 38nm) and three different ratios (0.5%, 1%, and 1.5%). The PSCM sample containing 38nm NT exhibited superior performance in terms of photocatalytic properties compared to the 28nm state. It was observed that the flow performance of PSCM mixtures with NT substitution is adversely affected regardless of the NT type. Mixtures containing NT with a lower particle size (28nm) had higher compressive and flexural strengths.

3D-printing of architected calcium silicate binders with enhanced and in-situ carbonation

ABSTRACT This paper investigates the use of architected cellular and solid designs of materials via additive manufacturing and in-situ CO2 circulation to augment the carbonation and mechanical properties of a calcium silicate-based cement (CSC) binder. A wollastonite-based binder was formulated for extrusion-based 3D-printing. Solid and cellular lamellar architectures were designed to probe the role of layered interfaces and higher surface area on the degree of carbonation (DOC), respectively. Two carbonation exposure scenarios, with and without in-situ carbonation were employed. The DOC, microstructural phases, and flexural strength were characterised using TGA, modified over-flow image analysis technique, and three-point-bending, respectively. By exploiting 3D-printing and harnessing the higher surface area of cellular architecture, the material obtained a significantly higher DOC (by 8.9-folds) and flexural strength (by 5.7-folds) compared to reference cast. In-situ carbonation of cellular architected materials can additionally improve early-stage deformation, DOC (by 12.9-folds) and flexural strength (by 16.5-folds), compared to cast.

Catalytic cyanate resin with polysulfide cation catalyst and its ultra‐high molecular weight polyethylene fiber composites for radome

AbstractCyanate (CE) resin and ultrahigh‐molecular‐weight polyethylene (UHMWPE) fiber are respectively important matrix and reinforcing material for lightweight and high wave‐transparent composites. However, the preparation and application of the composites is limited by the mismatch of molding temperature between CE resin and UHMWPE fiber. The best method to solve this problem is to catalyze the CE resin curing reaction and reduce its molding temperature from 270 to 135°C, which is the upper heat‐resistance temperature of UHMWPE fiber. In this study, the polysulfide catalyst (PSC) was used to catalyze CE resin curing reaction, reduce the curing reaction activation energy and the molding temperature. The apparent activation energy of the CE‐PSC resin decreases from 107.2 to 60.7 kJ mol−1, and the glass transition temperature of the CE‐PSC resin is 257.2°C, flexural strength and tensile strength are 120.2 and 60.8 MPa, respectively. As a result, the CE‐PSC/UHMWPE fiber composites, which are molded at the matching temperature of 135°C, have low density of 1.05 g cm−3, low dielectric constant of 2.4, low dielectric loss of 0.006, and high wave transmittance of 92.2%. Therefore, the CE‐PSC/UHMWPE fiber composites have wide application prospect in the field of light weight and high wave‐transparent composites.Highlights A novel catalytic CE resin can be cured at 135°C with low dielectric properties. The processing temperature mismatch between CE and UHMWPE fiber was solved. Catalytic CE/UHMWPE composites have lightweight and high wave‐transparent properties.

Long-Term Drying Shrinkage Strain of Engineered Cementitious Composite Concrete Contains Polymeric Fibers

The lack of concrete tensile stress endurance led to the invention of engineered cementitious composite. However, the absence of gravel from the mixture in addition to the high binder content may lead to high shrinkage strain. Therefore, a radical solution to this problem is worth to be anticipated. The importance of this research lies in investigating the long-term drying shrinkage strain of the engineered cementitious composite since there is a lack of information regarding this behavior. Mixes of 30 and 60 MPa strengths were produced with polyvinyl alcohol fibers PVA-ECC and polypropylene fibers PP-ECC. The drying shrinkage strain of PVA-ECC mixes has been compared to PP-ECC mixes for both short term (0–28 days) and long term (0–360 days). Results indicated that all PVA-ECC mixes exhibited lower drying shrinkage strains than PP-ECC mixes. The ultimate drying shrinkage strain was recorded to be 1200 microstrain at 28 days. The increment in drying shrinkage strain after 28 days was 5.6% in PVA-ECC mixes when compared to that in PP-ECC mixes which was 6.77%. For high strength levels, the drying shrinkage strain at the age of 360 days declared a reduction of 3.5% for PVA-ECC compared to PP-ECC mixes. Also, it was lower for mixes with 60 MPa (6.3%) than for mixes with 30 MPa (7.6%). Therefore, despite the higher cement content for mixes with 60 MPa strength, the higher fiber volume fraction and the higher PVA solution percentage restricted the drying shrinkage strain increment. The research also addresses some mechanical tests of engineered cementitious composite concrete such as compressive strength, flexural strength, and strain capacity that may provide a strong relation to the drying shrinkage behavior of the different mixes. The scanning electron microscope images were involved in this research to declare the impact of fiber types on the microstructure of the ECC mixes.

Feasibility study of replacing part of cement by igneous rock powder as cementitious material: based on mortar macroscopic properties and microstructure

To address the increasing demand for cement and promote sustainable development, the utilization of igneous rock powder as a supplementary material to partially replace cement has emerged as an effective strategy. In this study, the fluidity and mechanical properties of the igneous rock powder-cement (IRP-OPC) composite system were investigated, and the hydration product and microstructure of IRP-OPC were analyzed by using TG/DSC, N2 adsorption-desorption curve (BET) and SEM. The experimental findings demonstrate that the performance of the andesite powder-cement composite cementing system (AP-OPC) surpasses that of tuff powder-cement slurry (TP-OPC) and granite powder-cement slurry (GP-OPC). When the dosage of andesite powder (AP) is 5%–15%, the flowability, flexural strength and compressive strength of cement mortar are improved. When the dosage is 10%, the 28-day compressive strength is 48.3 MPa. Under the condition of low content (10%), part of Ca(OH)2 is fully consumed by active SiO2 in AP and reacts to form C-S-H. Hydration products and AP particles with small particle size are filled into the structural gap, which refines the pore structure of cement slurry, and the increase in compactness provides support for the development of strength in the later stage. The use of 5%–15% AP instead of OPC can improve fluidity and meet the strength requirements of P.O 42.5 Portland cement. This substitution not only reduces engineering costs but also enhances resource utilization.

Study on Mechanical Properties of Polymer Composites Filled with Nano Egg-shell Powder

Polymeric materials, when reinforced with synthetic fibers like glass, carbon, and aramid, offer notable advantages including increased stiffness and strength-to-weight ratio compared to conventional materials such as wood, concrete, and steel. Among these options, glass fiber stands out due to its affordability and widespread availability. Glass fiber reinforced polymer composites exhibit moderate mechanical properties, which can be significantly enhanced by incorporating nano fillers like eggshell powder. This study explores the utilization of nano eggshell powder as well as methods for effectively integrating nano fillers into polymer composites to create value-added products. Four types of composites, varying in weight proportions of nano eggshell powders, were prepared using the hand lay-up technique for mechanical and thermal characterizations. Various mechanical properties including tensile strength, flexural strength, impact behavior, as well as thermal properties via TGA and DMA analysis were investigated. The results indicate that incorporating the optimal amount of nano fillers significantly improves the overall strength of glass fiber reinforced composite materials, leading to cost savings of over 30%. This suggests that nano eggshell fillers hold great potential in composite manufacturing, particularly for substituting high-cost glass fibers in low load-bearing applications.

Impacts of Aramid Fiber (PPTA), Glass Wool (GW), Aluminum (Al), and Silicon Carbide (SiC) Particles on Mechanical Behavior of Epoxy Hybrid Composites and their Morphological Investigation

AbstractParticle‐reinforced polymer composites have figured prominently in technological appliances owing to their high mechanical modulus and strength. Due to the obvious demand for lighter but more resilient composites to substitute heavy metal parts, several investigations have been made into particle‐based composites. The current research investigates the impact of reinforcing aramid fiber (PPTA), glass wool (GW), aluminum (Al), and silicon carbide (SiC) powder into an epoxy matrix on aspects of mechanical and morphological characteristics. Hand lay‐up technology was performed to manufacture composites at five different degrees of reinforcement loading (5, 10, 20, 30, and 40 wt. %). SEM and optical microscopes were used for microstructural investigation in order to evaluate the cohesion and dispersion of the reinforcing particles across the matrix phase of the hybrid composites. The elongation at break, flexural strength, flexural modulus, and hardness of epoxy‐PPTA‐GW−Al‐SiC hybrid composites improved, whereas the tensile strength and impact strength decreased from 5 wt. % to 40 wt. % loading. Among fabricated hybrid composite compositions, the morphological and mechanical characteristics obtained at 40 wt. % PPTA, GW, Al, and SiC powder loading are the best among all others.

Effect of nano-particle weight percent on the flexural strength of Jute/kenaf/glass fiber composite using RSM

Effect of nano-particle weight percent on the flexural strength of Jute/kenaf/glass fiber composite using RSM

Mechanical Characterization of Hybrid Steel Wire Mesh/Basalt/Epoxy Fiber-Reinforced Polymer Composite Laminates

Hybrid composite materials have been widely used to advance the mechanical responses of fiber-reinforced composites by utilizing different types of fibers and fillers in a single polymeric matrix. This study incorporated three types of fibers: basalt woven fiber and steel (AISI304) wire meshes with densities of 100 and 200. These fibers were mixed with epoxy resin to generate plain composite laminates. Three fundamental mechanical tests (tensile, compression, and shear) were conducted according to the corresponding ASTM standards to characterize the steel wire mesh/basalt/epoxy FRP composites used as plain composite laminates. To investigate the flexural behavior of the hybrid laminates, various layer configurations and thickness ratios were examined using a design of experiments (DoE) matrix. Hybrid samples were chosen for flexural testing, and the same procedure was employed to develop a finite element (FE) model. Material properties from the initial mechanical testing procedure were integrated into plain and hybrid composite laminate simulations. The second FE model simulated the behavior of hybrid laminates under flexural loading; this was validated through experimental data. The results underwent statistical analysis, highlighting the optimal configuration of hybrid composite laminates in terms of flexural strength and modulus; we found an increase of up to 25% in comparison with the plain composites. This research provides insights into the potential improvements offered by hybrid composite laminates, generating numerical models for predicting various laminate configurations produced using hybrid steel wire mesh/basalt/epoxy FRP composites.

Cyclic fatigue behavior of Y‐TZP nanostructures with non‐homogeneous yttria distribution

AbstractNanostructured Y‐TZP samples with Non‐Homogeneous Yttria Distribution (NNHYD) were prepared by mixing co‐precipitated 3Y‐TZP powder (Tosoh TZ‐3Y) with yttria‐free monoclinic powder (Tosoh TZ‐0), yielding an overall yttria content of 2 mol%. The cyclic fatigue behavior of NNHYD was evaluated by Step‐Stress Accelerated Life Testing (SSALT) and mechanical cycling in a biaxial flexural strength test (BFST) setup and compared to Conventional Submicrometric 3Y‐TZP (CS). Physical, structural, microstructural, and mechanical characterizations of all groups were also evaluated and compared before and after artificial aging in autoclave. NNHYD presented a higher capacity for damage accumulation and maintenance of phase transformation potential than CS, associated with elevated resistance to the propagation of Low‐Temperature Degradation (LTD). A nanostructured 3Y‐TZP surface layer introduced in NNHYD by dip coating (DC‐NNHYD) improved resistance to LTD at the cost of reduced reliability under cyclic fatigue by increasing the stability of the tetragonal phase. This surface alteration highlights the impact of surface properties on mechanical performance. The results of this study present practical possibilities to help achieve the ideal balance between strength, toughness, and LTD resistance to improve the lifetime of zirconia‐based biomaterials.

Wood Quality of Young Tectona grandis L. f. Trees and Its Relationship with Genetic Material and Planting Site in Mato Grosso, Brazil

Tectona grandis L. f. (teak) is highly valued in the international market, but its volume and properties vary depending on its genetic material and planting site. Evaluating these factors is crucial for promoting new plantations. Therefore, this study aimed to assess the impact of genetic material (clones TG1 and TG3 and seminal material) and planting site (Nova Maringá and Água Boa, Mato Grosso, Brazil) on morphological parameters (heartwood, sapwood, bark, pith proportions, and pith eccentricity), physical properties (shrinkage and air-dry density), and mechanical properties (static bending strength—fm, compressive strength—fc0, Janka hardness—fH90, and shear strength—fv0). For this purpose, we sampled five trees aged 13 years per genetic material from commercial plantations. In Nova Maringá, trees exhibited, on average, 56.07% heartwood, while in Água Boa, this value was less than 50%. Seminal material showed the lowest percentage of heartwood (49.2%). The pith percentage was significantly greater in Água Boa than in Nova Maringá, regardless of the genetic material. We observed the highest standard deviation (5.61) in pith eccentricity for the seminal material. Both the planting site and genetic material influenced the air-dry density (~12% moisture content), which ranged from 0.535 to 0.618 g·cm−3. Trees grown in Nova Maringá produced wood with higher dimensional stability than those from Água Boa, exhibiting a 14% lower radial shrinkage and a 6% lower volumetric variation. In Nova Maringá, the wood from the seminal material exhibited greater resistance. On the other hand, in Água Boa, that material showed lower resistance (fv0, fm, and fc0), or there was no significant difference (fH90) compared to the clonal materials. When comparing the clonal materials (TG1 and TG3) at each planting site, they demonstrated similar mechanical properties. The variability in physical and mechanical properties among different genetic materials and planting locations highlights the need to select appropriate teak genetic materials for each region. We concluded that more productive teak clones can be selected without compromising the physical and mechanical properties of the wood.

The effects of 3D printing designs on PLA polymer flexural and fatigue strength

Abstract This study assessed the flexural and fatigue strength of the 3D-printed polylactic acid (PLA) samples across diverse printing designs and parameters. The experiment setup included different layer heights, first layer thicknesses, infill densities, top/bottom infill patterns, extruder temperatures, perimeters, and different types of solid layer top and bottom. Our findings suggest that the fatigue strength of PLA printing specimens is more significantly influenced by an increase in the thickness of the first layer compared to flexural strength. Specifically, the rate of increase in bending strength is lower in cases of layer height and initial layer height in contrast with other factors. Notably, specimens with an initial layer thickness of 0.4 mm reached the highest number of cycles until failure, recording 21022 cycles. Furthermore, the study identifies the infill pattern's impact on strength, highlighting that the line infill pattern type case has the highest bending strength of 75.97 Mpa and surpasses the honeycomb pattern in bending strength. Compared to the Honeycomb pattern, the rectilinear design has 2.1% higher bending strength. The number of cycles to failure of the rectilinear pattern is greater than those of the honeycomb pattern. In comparison to other patterns, the Rectilinear Top/Bottom infill pattern has a higher interest rate of 27.5% for bending strength and 200.83% for fatigue strength. Additionally, greater bending and flexural strength are obtained by raising the solid layer top, bottom, and perimeter values, respectively. In comparison to the other temperatures, the bending strength and fatigue strength are highest at 200°C. Therefore, the first layer height of 0.4 mm, the top/bottom rectilinear infill pattern, the extruder temperature of 200 °C, the perimeter value of 3, the solid layer/top value of 3, and the solid layer/bottom value of 3 are the optimal values for the part subjected to at the same time bending strength combined with fatigue strength. This study may provide an overview of bending and fatigue strength in connection to printing design and printing parameters, as well as the ideal parameters for 3D printing with the PLA material.

Multi-Criteria Optimization of SBR-Modified Mortar Incorporating Polyethylene Terephthalate Waste

Thermosetting post-consumer plastics like polyethylene terephthalate (PET) raise serious recycling challenges, leading frequently to disposal through incineration or landfilling. This study assesses the feasibility of cementitious materials containing PET additions including the influence of cement content, water-to-cement ratio (w/c), styrene-butadiene rubber (SBR) polymer additions, and PET volume on the fresh and hardened properties. The mixture proportioning followed the Taguchi methodology, which entailed the utilization of four factors, each possessing three different levels to create an L9 orthogonal matrix. The assessment included diverse performance indicators such as flow, compressive strength, flexural strength, bond strength, water absorption, and resistance to carbonation. Test results revealed that the incorporation of SBR and PET degraded the compressive strength, albeit this can be restored by increasing the cement content and/or reducing w/c. The addition of SBR significantly improved the flexural and bond strengths yet curtailed the water absorption and resistance to carbonation due to increased closed porosity that facilitated the transport properties. The multi-criteria optimization approach (TOPSIS) indicated that superior performance can be achieved using a cement content of 525kg/m3, w/c of 0.55, SBR of 3.5%, and PET incorporation of 4.5%. These parameters were subsequently employed in the development of multivariate regression models, allowing for the prediction of fresh and hardened properties in SBR-PET mortar.

Flexural Strength of Different Monolithic Computer-Assisted Design and Computer-Assisted Manufacturing Ceramic Materials Upon Accelerated Aging.

The durability of ceramic is crucial, which is probably influenced by aging. This study evaluated the effect of aging on flexural strength of different ceramics. One-hundred twenty ceramic discs (Ø 12 mm, 1.5 mm thickness) were prepared from zirconia-reinforced lithium silicate (ZLS, C), lithium disilicate (LS2, E), precolored yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP, Ip), and customized color Y-TZP (Ic). Samples were randomly divided into two groups for accelerated aging (A) between 5 and 55°C water baths, 30-second immersing time each, for 10,000 cycles, and nonaged group (N), serving as control. Biaxial flexural strength (σ) was evaluated utilizing the piston-on-three-balls at 0.5 mm/min speed. Analysis of variance and Tukey comparisons were determined for significant differences (α = 0.05). Weibull analysis was applied for survival probability, Weibull modulus (m), and characteristic strength (σo). Microstructures were evaluated with scanning electron microscopy and X-ray diffraction (XRD). The highest σ and σo were seen for IcN, followed by IcA, IpN, IpA, EN, CA, CN, and EA, respectively. CN showed the highest m, while EA showed the lowest m. Significant differences of σ for each ceramic were indicated (p < 0.05). Aging caused a significant difference in σ (p < 0.05). XRD showed t→m phase transformation of Ip and Ic after aging. Aging affected strength of ceramics. Comparable strength between LS2 and ZLS was evidenced, but both were less strength than Y-TZP either aging or non-aging. Comparable strength between precolored Y-TZP and customized color Y-TZP was indicated. Better resisting aging deterioration of Y-TZP than LS2 and ZLS is suggested for fabrication restorative reconstruction.

Strong and Tough MXene Bridging-induced Conductive Nacre.

Nacre is a classic model, providing an inspiration for fabricating high-performance bulk nanocomposites with the two-dimensional platelets. However, the "brick" of nacre, aragonite platelet, is an ideal building block for making high-performance bulk nanocomposites. Herein, we demonstrated a strong and tough conductive nacre through reassembling aragonite platelets with bridged by MXene nanosheets and hydrogen bonding, not only providing high mechanical properties but also excellent electrical conductivity. The flexural strength and fracture toughness of the obtained conductive nacre reach ~ 282 MPa and ~ 6.3 MPa m1/2, which is 1.6 and 1.6 times higher than that of natural nacre, respectively. These properties are attributed to densification and high orientation degree of the conductive nacre, which is effectively induced by the combined interactions of hydrogen bonding and MXene nanosheets bridging. The crack propagations in conductive nacre are effectively inhibited through crack deflection with hydrogen bonding, and MXene nanosheets bridging between aragonite platelets. In addition, our conductive nacre also provides a self-monitoring function for structural damage and offers exceptional electromagnetic interference shielding performance. Our strategy of reassembling the aragonite platelets exfoliated from waste nacre into high-performance artificial nacre, provides an avenue for fabricating high-performance bulk nanocomposites through the sustainable reutilization of shell resources.

Determining the Properties of Unfired Stabilized Kaolinitic Clay Brick for Sustainable Construction

Kaolin is one of the most vital industrial minerals whose application is reliant on its chemistry and structural makeup. This research attempts to determine the properties of unfired kaolinitic clay bricks for sustainable construction. Samples of the material were pre-treated and analyzed to obtain their physical and refractory properties, such as chemical composition, microstructure, moisture content, dry density, linear shrinkage, plastic index, and crushing strength. The results revealed that the clay comprises high percentages of silicon and alumina oxides being 75.6% and 17.0% of the total oxide composition respectively. The clay also contained some residual impurities in the form of metallic oxides i.e., oxides of iron, sodium, calcium, potassium, manganese, and lead. Characterization tests on the clay presented a specific gravity of 2.66, liquid limit of 38, plastic limit of 25.9, and plasticity index of 12.1 which classifies the clay as low-plasticity clay based on the Unified Soil Classification System. The river sand used was distributed between 0.06 – 3 mm falling within the category of medium and fine sand. The aggregate fineness modulus was obtained as 3.03%. The coefficient of uniformity was lower than 4.0 and thus classified as being uniformly graded. Stabilization of the clay with sand and lime resulted in decreased compression and flexural strength but increased durability. The results imply that kaolinitic clay can be used in an unfired form for earth construction.

Strong and Tough MXene Bridging‐induced Conductive Nacre

Nacre is a classic model, providing an inspiration for fabricating high‐performance bulk nanocomposites with the two‐dimensional platelets. However, the “brick” of nacre, aragonite platelet, is an ideal building block for making high‐performance bulk nanocomposites. Herein, we demonstrated a strong and tough conductive nacre through reassembling aragonite platelets with bridged by MXene nanosheets and hydrogen bonding, not only providing high mechanical properties but also excellent electrical conductivity. The flexural strength and fracture toughness of the obtained conductive nacre reach ~ 282 MPa and ~ 6.3 MPa m1/2, which is 1.6 and 1.6 times higher than that of natural nacre, respectively. These properties are attributed to densification and high orientation degree of the conductive nacre, which is effectively induced by the combined interactions of hydrogen bonding and MXene nanosheets bridging. The crack propagations in conductive nacre are effectively inhibited through crack deflection with hydrogen bonding, and MXene nanosheets bridging between aragonite platelets. In addition, our conductive nacre also provides a self‐monitoring function for structural damage and offers exceptional electromagnetic interference shielding performance. Our strategy of reassembling the aragonite platelets exfoliated from waste nacre into high‐performance artificial nacre, provides an avenue for fabricating high‐performance bulk nanocomposites through the sustainable reutilization of shell resources.

High‐quality and efficient recovery of waste agricultural mulch film mixture via solid‐state shear milling technology

High‐quality and efficient recovery of waste agricultural mulch film mixture via solid‐state shear milling technology

Impact of accelerated aging cycles on the performance of extruded cement-based composites reinforced with non-bleached eucalyptus fibers.

Thermo-mechanical pulping produces well-individualized fibers compared to wood particles and less fragile fibers compared to Kraft pulping, besides presenting higher volume, higher yield, and lower production cost, which can be an exciting alternative for the fiber-cement industries. This study evaluated the impact of soak and dry-aging cycles on the performance of extruded composites reinforced with non-bleached eucalyptus fibers. The cement matrix comprised cement (70%) and limestone (30%). Composites were reinforced with 1 to 5% of eucalyptus fiber by cement mass and tested on the 28th day of cure at 99% relative humidity and after 400 accelerated aging cycles. The water absorption and apparent porosity gradually increased with the reinforcement level. Composites with 4 and 5% fibers showed the highest toughness (0.21 and 0.23kJ/m2, respectively). The aging by 400 soak-dry cycles reduced the composites' water absorption and apparent porosity. The modulus of elasticity (MOE), rupture (MOR), and toughness increased, except for toughness for composites reinforced with 1 and 5% fibers, explained by the cementitious matrix's continuous hydration, fiber mineralization, and natural carbonation. In general, eucalyptus thermo-mechanical fibers were suitable for producing cementitious composites. Cementitious composites with 3% fibers presented a higher MOR, MOE, low water absorption, and apparent porosity after 400 accelerated aging cycles. In addition, the composites with 4% fibers also presented remarkable improvements in these properties. The aging cycles did not result in composites with less resistance, a positive fact for their application as tiles and materials for external use in civil construction.

The Use of Phosphogypsum as a Source of Raw Materials for Gypsum-Based Materials

Gypsum binders and the products based on them are widely in demand in the construction materials market, which is due to their easy production technology, lower energy consumption, and low environmental impact in relation to Portland cement. Not only natural gypsum (NG), but also phosphogypsum (PG), which is a by-product of the synthesis of orthophosphoric acid from phosphorite rock, can be used as a source of raw materials for the production of gypsum materials. PG is produced annually in large quantities throughout the world. In chemical composition, PG mainly consists of calcium sulfate dihydrate CaSO4·2H2O, so it is a good potential analogue of natural gypsum, which is used as the main component of gypsum building materials. Thus, the useful recycling of PG as a technogenic resource with valuable properties will expand the raw material base for the production of gypsum materials. This approach to handling technogenic resources fits well with the principles of a circular economy. However, like any technogenic resource, PGs from different enterprises normally differ in their deposits of the original phosphate rock and production technologies. Therefore, PG contains a large number of undesirable impurities, the proportion and composition of which vary over a wide range. This feature does not allow for predicting the properties of PG-based materials without a preliminary detailed study of PG. This research was aimed at carrying out a comprehensive study of the characteristics of PGs from three different industrial plants to evaluate their relationship with the properties of gypsum materials based on them. It was found that PGs have significant differences in their structural and morphological characteristics both in relation to each other and in relation to NG. Also, binders based on PG and NG have significant differences in their physical properties. The average density, compressive strength, and flexural strength for the PG binders with equal workability are lower than those of NG binders. At a water/solid ratio (W/S) &lt; 0.7, all PG binders exhibit comparable compressive strength to NG binders. Thus, PG can act as an alternative to natural gypsum in gypsum binders.