This study investigated the resistance of recycled aggregate concrete (RAC) to chloride penetration under freeze-thaw cycles using both numerical simulation and experimental validation. A five-phase mesoscale model of RAC was developed. The salt freeze-thaw test was conducted to validate the simulated values and explore the effects of different recycled coarse aggregate (RCA) substitution ratios, as well as varying dosages of fly ash and superfine fly ash, on chloride concentration in RAC. The experimental data showed satisfactory agreement with the simulated values, confirming the model's validity. Additionally, the RCA volume fraction, interfacial transition zone (ITZ) thickness, and adhesive ratio of old mortar were analyzed using simulation. The variation patterns of compressive strength, relative dynamic elastic modulus, and mass loss of RAC also revealed the mechanisms by which RCA substitution ratio and the dosages of fly ash and superfine fly ash act under salt freeze-thaw conditions. This study provides guidance for enhancing the resistance of RAC to chloride penetration and its durability under freeze-thaw conditions.
The complexity and heterogeneity of tumors make monotherapy inadequate for effective tumor elimination, highlighting the urgent need for multifunctional synergistic therapeutic strategies. In this study, a near-infrared (NIR)-responsive multimodal therapeutic nanoplatform (FSINPs) was constructed by simple adsorption of indocyanine green (ICG) and Fe3+ onto silk fibroin nanoparticles. Molecular docking showed that ICG binds stably to silk fibroin mainly via hydrogen bonds. Density functional theory (DFT) calculations predicted that Fe3+ strongly coordinates with the sulfonate groups of ICG and quenches ICG fluorescence via intermolecular charge transfer. Under conditions mimicking the acidic and high-glutathione tumor microenvironment, the ICG-Fe3+ coordination is disrupted, leading to fluorescence recovery of FSINPs. Fe3+ catalyzes the Fenton reaction to generate hydroxyl radicals (·OH), thereby achieving chemodynamic therapy (CDT). Upon 808 nm laser irradiation, ICG acts as a dual photosensitizer capable of both photothermal therapy (PTT) and photodynamic therapy (PDT), generating local hyperthermia with a photothermal conversion efficiency as high as 48.7% and producing singlet oxygen (1O2). The photothermal effect facilitates ·OH production, and CDT enhances photodynamic efficacy. The synergistic action of the three therapeutic modalities results in potent light-activated cytotoxicity toward tumor cells. In vivo experiments demonstrated that FSINPs enable tumor microenvironment-responsive fluorescence imaging for over 48 h and achieve complete tumor eradication in a 4T1 tumor model without obvious systemic toxicity. This study provides a new strategy for constructing activatable imaging and highly synergistic PTT/CDT/PDT-integrated silk fibroin-based nanomedicines and offers computational chemistry references for their rational design and development.
Cu-Sn-Ti metallic-bonded CBN (Cubic Boron Nitride) abrasives are widely applied in the precision grinding of superhard materials. However, their high density and high toughness easily lead to poor grain protrusion and inadequate self-sharpening. In this work, ceramic glass powder was incorporated to modify the Cu-Sn-Ti binder, thereby fabricating composite-bonded CBN abrasive blocks with qualified mechanical properties and excellent self-sharpening performance. Flexural strength of abrasive blocks and microhardness of composite binders were measured; microstructure was characterized, phase composition was analyzed by XRD, and tribological tests were carried out between CBN blocks and silicon nitride abrasives. The results indicate that at glass powder contents of 2.94-10.22 wt%, the flexural strength of CBN blocks decreases by 32.5-89.4%, and binder microhardness reduces by 26.5-58.3%. At high brazing temperature, Ti and Cu from Cu-Sn-Ti alloy react with Si and Al in glass powder at the interface to form new phases including Ti2O3, Ti5Si3 and Ti(Cu,Al)2, which facilitates favorable interfacial bonding among the alloy matrix, glass phase and CBN grains. With increasing glass powder content, the strength decline gradually slows down. The overall wear resistance of abrasive blocks declines. SEM observations on worn CBN blocks and their composite binders reveal the formation of micropores within glass-containing binders, accompanied by a shift in the fracture mode of CBN abrasives upon glass powder addition. Comprehensive experimental analysis indicates that the No.3 sample with 8.33 wt% glass powder possesses the optimal overall performance.
High-volume injection molding systems for plastic part production operate under severe thermo-mechanical loading repeated at high production rates. Therefore, premature breakage of hot-work tool steel core inserts directly interrupts production continuity and creates a recurrent maintenance problem. To address this failure mode, this study collected production inputs and failure evidence and established a reliable interpretation by linking computer-aided engineering simulations of the plastic injection molding process, structural FEA of the insert response, and cumulative fatigue assessment using a TMF-creep damage model. This integrated approach provides a comprehensive framework for failure root-cause identification and service-life prediction and improving insert durability in mass-manufacturing environments.
Hard and brittle material components with complex curved surfaces are widely used in critical foundational parts within aerospace, optoelectronics, and other fields. Their machining quality directly determines the performance and reliability of high-end equipment. However, the inherent properties of hard and brittle materials make them prone to surface/subsurface damage during traditional polishing processes, and maintaining the form accuracy of complex curved surfaces is challenging. Although abrasive waterjet polishing enables non-contact flexible processing, its energy efficiency is low. Additionally, although ultrasonic-assisted polishing can improve material removal, its spatial localization is insufficient, limiting energy utilization efficiency. To address these issues, this paper proposes a novel method of focused, ultrasonic, vibration-assisted abrasive waterjet polishing. The influence of the radiation force and cavitation force of the focused ultrasonic field on abrasive particle motion is analyzed, and analytical equations for abrasive particle velocity are established. Subsequently, single-factor and response surface methodologies are employed to systematically evaluate the influence of process parameters on machining quality and efficiency. The material removal process during FUAP involves both plastic shearing/chip formation and localized brittle fracture. Focused ultrasonic assistance promotes micro-cutting and plastic shearing, while localized crushing pits indicate that brittle fracture remains non-negligible. The focused ultrasound superimposes alternating stress onto the impact action, mitigating microscale crushing pit defects during the brittle removal process of monocrystalline silicon. Furthermore, appropriately increasing ultrasonic power, enlarging abrasive particle size, and raising abrasive concentration all contribute to enhanced material removal from monocrystalline silicon. Adjusting the nozzle height to the effective region of the focused ultrasonic energy field promotes material removal via chip formation while avoiding pit defects caused by excessive fracture. These results suggest that focused ultrasonic energy can be effectively integrated into abrasive waterjet polishing to enhance material removal while suppressing brittle surface defects, thereby offering a promising strategy for the ultra-precision finishing of hard and brittle components with complex curved surfaces.
Improving the flame-retardant performance of asphalt is particularly important for tunnel pavements, where confined environments can intensify fire hazards and smoke accumulation. This study prepared different modified asphalt binders to investigate their flame-retardant performance and rheological properties. The limiting oxygen index and smoke density rating were first used to evaluate the flame-retardant and smoke-suppression performance. Frequency sweep tests were then conducted to analyze the rheological behavior, aging characteristics, and low-temperature cracking resistance of the binders. Finally, microscopic tests were performed to reveal the thermal decomposition behavior and modification mechanism. Results showed that the incorporation of FR02 increased the limiting oxygen index of the warm-mix modified binders by more than 47%. Among the investigated binders, 13% fast-melting warm-mix flame-retardant composite modifier (SBS-WZ) exhibited the highest limiting oxygen index of 30.95% and the lowest smoke density rating of 57.73, indicating the best experimentally measured flame-retardant and smoke-suppression performance. At a reduced frequency of approximately 10-2 rad/s, the unaged 13%SBS-WZ binder exhibited a complex modulus of approximately 2.0 × 105 Pa, nearly one order of magnitude higher than those of the conventional 4%SBS- and 4%fast-melting SBS modifier (SBS-T), while its phase angle was approximately 6-10° lower. At -24 °C, the creep stiffness and creep rate of the unaged 13%SBS-WZ binder were approximately 654 MPa and 0.246, respectively. After Pressure Aging Vessel (PAV) ageing, these values changed to approximately 720 MPa and 0.237. Moreover, the onset decomposition temperature of 13%SBS-WZ was 392.1 °C, which was 17.2 °C higher than that of 4%SBS-T. Together with its higher residual mass, this result suggests enhanced thermal stability and residue-forming potential, which may partly explain the measured improvements in flame-retardant and smoke-suppression performance. However, the increased complex modulus and reduced creep rate indicate a concurrent loss of low-temperature flexibility. The findings can provide theoretical guidance and technical support for the application of this material in tunnel asphalt pavements.
To address the dependence on organic solvents, costly silicon precursors, and complex processing in conventional silica aerogel preparation, this study developed a green and low-cost aqueous route using water glass as the silicon source. The sol-gel process was optimized through an orthogonal experimental design by regulating precursor concentration, pH, temperature, and catalyst dosage, enabling the formation of a stable three-dimensional silica network. Under the optimized conditions, the unmodified silica aerogel exhibited low density, high porosity, and a typical mesoporous structure, with a specific surface area of 707.87 m2/g, an average pore size of 5.75 nm, and a thermal conductivity of 0.0408 W/(m·K). After HMDS vapor-phase modification, hydrophobic methyl groups were introduced onto the aerogel surface, increasing the water contact angle to 132.3°. Among the modified samples, S3 showed the lowest thermal conductivity of 0.0360 W/(m·K), indicating good thermal insulation performance. This work provides a feasible strategy for preparing hydrophobic silica aerogels through a cost-effective aqueous process, showing potential for greener and large-scale production of silica aerogel materials.
This study systematically investigates the effects of water-to-binder ratio, total binder content, silica fume content, and fly ash content on the fluidity and compressive strength of Type IV cement-based grouting materials. An L16(44) orthogonal experimental design was adopted to evaluate the influence of these four factors on initial and 30 min slump flow, as well as 1-day, 3-day, and 28-day compressive strength. The range analysis results indicate that silica fume content exerts the most significant effect on initial slump flow, while the water-to-binder ratio predominantly governs the 30 min slump flow and early-age compressive strength, such as at 1 day and 3 days. The total binder content is identified as the key factor influencing the 28-day compressive strength. Furthermore, supplementary tests on the combined incorporation of fly ash and silica fume reveal that silica fume enhances early-age strength but reduces fluidity, whereas fly ash improves fluidity but promotes later-age strength development, with an optimal substitution range for both admixtures. Microstructural analyses including XRD and SEM and hydration heat tests further elucidate the underlying mechanisms, demonstrating that the effects of the two admixtures optimize the hydration process and microstructure densification. Based on the comprehensive evaluation, the optimal mix proportion was determined as A3B2C4D2, corresponding to a water-to-binder ratio of 0.31, a fly ash content of 15%, a total binder content of 690 kg/m3, and a silica fume content of 8.5%. This optimized formulation achieves a balanced performance in both workability and strength development.
Thermomechanical processing (TMP) is of critical importance for tailoring microstructures and properties of high-strength titanium alloys and their composites. In this study, mechanical response and microstructural evolution mechanisms of 2 vol.% TiB/Ti-5Al-5Mo-5V-3Cr-1Zr (Ti-55531) matrix composites during isothermal compression at varied deformation temperatures (785-925 °C) and strain rates (0.001-1 s-1) are comprehensively investigated by kinetic calculation and microstructural characterization. Strain-compensated constitutive equations in α + β and β phase regions were established. Results show that deformation temperature and strain rate influence flow behavior and microstructure through dynamic recovery (DRV) and dynamic recrystallization (DRX) of the β phase as well as dynamic spheroidization of the α phase. Crucially, three DRX mechanisms of β phase were identified, wherein TiB-induced β-DRX dominates, with α-assisted β-DRX and continuous dynamic recrystallization (CDRX) as secondary mechanisms. Dynamic spheroidization mechanisms of the α phase, including β-wedge penetration as well as α interaction and kinking, were elucidated. A comprehensive microstructural evolution mechanism map was constructed, and an optimized hot-processing window was proposed. Notably, the introduction of TiB significantly promotes β-DRX, which tends to randomize crystallographic orientations of the β phase, and enhances microstructural stability. This study provides theoretical complement and practical guidance for hot processing and microstructure control of metastable β titanium matrix composites.
Portland cement production accounts for roughly 8% of anthropogenic CO2 emissions, driving interest in low-carbon geopolymer binders. One-part ("just-add-water") geopolymers, which replace hazardous liquid activators with a dry, pre-blended solid activator, are especially suited to field deployment where handling safety and logistics are decisive. However, their formulation space is combinatorially vast, and trial-and-error development cannot efficiently navigate it. This paper reviews one-part geopolymer science, presents a new comparative and interpretable ML analysis of a published 80-mixture one-part fly-ash/ground granulated blast-furnace slag (GGBS, hereafter slag) geopolymer dataset from twelve studies, and proposes an AI-assisted design framework. The ML demonstration targets 28-day compressive strength only. Under leave-one-source-out (LOSO) cross-validation-the appropriate test for a literature-pooled dataset-gradient-boosted trees achieved R2 = 0.61 (RMSE = 15.5 MPa; 95% bootstrap confidence interval on R2, 0.44-0.75), well above a linear baseline (0.36), suggesting that non-linear structure transfers across studies; a random split gives a higher but less reliable R2 = 0.90 on only 16 test mixtures. Because fly-ash and slag contents are near-perfectly anti-correlated (r=-0.99), we model the precursor axis as a single slag fraction descriptor; SHAP then identifies this precursor balance and the activator's Na2O dosage as the dominant statistical predictors of strength in this dataset, an ordering consistent with known activation chemistry; causal confirmation of these associations awaits the experimental validation stage of the proposed framework. Demonstrated for strength only, at paste level, the framework offers a transferable route toward multifunctional low-carbon binders for protective and infrastructure applications; the multifunctional extensions are proposed, but not yet demonstrated.
Advanced dental implant systems are clinically successful when their material properties, surface topography, abutment geometry and implant-abutment connection design support both mechanical stability and biological integration. In Morse-tapered implant-abutment systems and conometric prosthetic retention systems, the precision of conical interfaces has traditionally been discussed mainly in biomechanical terms; however, their clinical performance also depends on the formation and maintenance of a stable peri-implant soft tissue seal. This review examines micro-computed tomography (µCT), with emphasis on synchrotron radiation-based phase-contrast micro-computed tomography (SR-PhC-µCT), as an advanced characterization strategy for evaluating how implant and abutment design influence the three-dimensional architecture of peri-implant connective tissues. The review summarizes the biological organization of the peri-implant mucosa, the technical basis of absorption- and phase-contrast microtomography, sample preparation protocols, segmentation workflows, artificial intelligence-assisted image analysis and quantitative morphometric descriptors of collagen organization. Particular attention is given to human retrieval and biopsy studies of Morse-tapered/conometric systems, where three-dimensional imaging has revealed interwoven circumferential and longitudinal collagen bundles around the transmucosal implant component. These microarchitectural features have been directly visualized by SR-PhC-µCT and histology and may represent a biomechanically plausible basis for mucosal sealing and force distribution. However, their direct relationship with marginal bone preservation and long-term clinical outcomes remains to be demonstrated in longitudinal studies. Within the scope of advanced dental materials, the novelty of this review lies in framing SR-PhC-µCT, correlative histology and AI-assisted segmentation as enabling tools within a materials-design framework for implant-abutment optimization. In this framework, peri-implant collagen architecture is interpreted as an exploratory structural readout of the interaction among connection design, abutment geometry, surface topography and biological response. This approach does not yet establish validated clinical biomarkers, but it may generate testable hypotheses for future studies aimed at improving peri-implant soft tissue stability and implant-abutment system design.
The optoelectronic properties of the lead-free perovskite CsSn0.5Ge0.5I3 are investigated by first-principles calculations and numerical simulations using SCAPS-1D. The energy-level alignment between transport layers and the perovskite layer is evaluated, resulting in the establishment of the PCBM/CsSn0.5Ge0.5I3/PEDOT:PSS structure. Key parameters, including bulk defect density, layer thickness, and electrode materials, are optimised, and the effects of resistance, illumination intensity, thermal stability, and carrier generation-recombination rates on device performance are analysed. The optimal device structure FTO/PCBM/CsSn0.5Ge0.5I3/PEDOT:PSS/C achieves a power conversion efficiency (PCE) of 24.50% and a fill factor (FF) of 80.01%. Machine learning (ML) algorithms are applied to predict photovoltaic parameters, with Random Forest (RF) exhibiting the highest accuracy. SHAP analysis identifies absorber layer thickness as the dominant factor influencing efficiency, providing guidance for experimental optimisation. This integrated approach offers a practical pathway for designing high-performance, stable, and environmentally sustainable perovskite solar cells (PSCs).
This study investigates the atomic-scale effects of hydrogen concentration and Ni content on crack propagation in Fe-Ni alloy models using molecular dynamics methods. A Mode I crack model with a (001)[100] orientation was constructed, and hydrogen atoms were locally introduced at the crack tip with concentrations of 5.3 at.% and 14.3 at.%. Fe-Ni alloy models with 5%, 10%, 15%, and 20% Ni were compared in terms of crack growth, dislocation evolution, stacking fault energy, and hydrogen diffusion. The results show that local hydrogen introduction has a limited effect on the peak stress-strain response, while hydrogen clearly accelerates crack propagation in the middle stage, especially at high concentrations. For the 10% Ni model, the middle-stage crack growth rate increases to 0.36 Å/ps under 14.3 at.% crack-tip hydrogen. Crack growth in all models shows three stages. The 15% Ni model exhibits a clear plateau in the second stage and the shortest final crack length. Further analysis shows that Ni content regulates dislocation behavior through stacking fault energy. At 15% Ni, sustained dislocation entanglement and high-density dislocation multiplication occur near the crack tip, which helps dissipate local stress. Hydrogen diffusion analysis indicates that hydrogen mobility is lower in the 15% Ni model, which may be related to hydrogen retention near dislocation-rich regions. A normalized comparison based on hydrogen diffusion and middle-stage crack growth rate further identifies 15% Ni as the lowest crack propagation tendency composition among the studied models. These results provide atomic-scale data for Ni-content optimization in hydrogen-resistant alloys, although the direct engineering transfer of the findings is limited by the length and time scales of molecular dynamics simulations.
To investigate the application potential of ultrafine composite powder (UCP) as a novel supplementary cementitious material to replace ground granulated blast-furnace slag (GBFS) in cement-based materials and its underlying mechanism, this study first compared the activity differences between UCP and GBFS and their effects on mortar workability. Subsequently, multiple characterization techniques including XRF, XRD, TG/DTG, FTIR, mapping, SEM-EDS, and BET were employed to systematically examine the morphology, composition, particle size distribution, and pore structure characteristics of the two powders. Results show that UCP exhibits slightly higher 3 d and 28 d strength activity indices than GBFS, but contributes less to strength progression between 3 and 28 days. In terms of chemical composition, UCP contains lower combined CaO + MgO + Al2O3 content but significantly higher C and Fe levels and alkalinity than GBFS. Phase and microstructural analyses further reveal that UCP is predominantly composed of GBFS, fly ash (FA), steel slag, limestone powder, gypsum, superplasticizer, and alkaline activator, and is characterized as a mesoporous material with pores arising from fragmented FA, unburned carbon residues, and grinding-induced cracks. Quantitatively, the BET specific surface area, Blaine specific surface area, and total pore volume of UCP are 2.47, 1.59, and 3.31 times those of GBFS, respectively. Therefore, the early-age activity advantage of UCP is mainly attributed to the filling effect, the additional nucleation sites provided by its larger specific surface area, and the chemical activation induced by alkali and gypsum.
The qualitative evolution of SARA fractions during asphalt binder aging is well established, but further validation is needed to demonstrate whether automated HPLC-SARA analysis can provide repeatable compositional indicators for systematic aging studies. In this work, the applicability of a previously optimized automated high-performance liquid chromatography (HPLC) workflow for saturate, aromatic, resin, and asphaltene (SARA) fractionation was evaluated for the monitoring of thermo-oxidative aging. Four penetration-grade asphalt binders were subjected to short-term aging and multiple long-term aging cycles, and the resulting SARA distributions were used to calculate the colloidal instability index (Ic). Fourier-transform infrared spectroscopy (FTIR) was used as an independent reference technique to evaluate carbonyl and sulfoxide oxidation indices. The automated HPLC-SARA method provided repeatable compositional indicators across all asphalt binders and aging conditions. As expected, aromatics progressively decreased whereas asphaltenes increased, while saturates showed only limited variations and resins behaved as an intermediate operational fraction. More importantly, Ic increased consistently with aging and showed a strong correlation with the FTIR carbonyl index (R2 = 0.84 when all asphalt binders and aging conditions were considered), whereas the sulfoxide index showed a more asphalt binder-dependent response. These results demonstrate that automated HPLC-SARA analysis can provide aging-sensitive compositional and colloidal indicators that are chemically consistent with independent FTIR oxidation markers. The proposed workflow represents a complementary tool for asphalt binder aging research and may support future studies aimed at linking compositional evolution with rheological and durability-related properties.
The scientific community and engineers are interested in simulating and analysing the behaviour of individual components and complex structures. This review article highlights progress in the area of modelling of structural materials based on the use of the finite element method. In addition to being described deterministically, the situation ahead of a possible stress concentrator is also defined using modern statistical techniques, and the behaviour simulation is explained in terms of length scales. Crack development and generation in the component are the main uses of the description of the impact of local microstructure on macrostructure. There are two predominant types of multiscale analysis: hierarchical and concurrent. Hybrid types also exist, but these are beyond the scope of this paper. Mainly, two-scale hierarchic simulations are illustrated hereafter. The modelling is dedicated to the following groups of materials: (i) crack initiation around inclusions, carbides at grain boundaries, and natural or artificial stress concentrators; (ii) composites with short or long fibres and pronounced interfaces; and (iii) combinations of (i) and (ii) in the case where the grain structure behaves like a short fibre. The authors draw on many years of experience in the field of numerical methods and, in particular, the modified finite element method.
Accurate state-of-health estimation of lithium-ion batteries under high-temperature conditions (40-50 °C) remains challenging because of accelerated electrochemical degradation and strongly nonlinear aging patterns. This paper presents a hybrid Ridge regression-convolutional bidirectional long short-term memory framework with a dual-level transfer learning strategy. A Ridge regression baseline first captures the global degradation trend, after which a convolutional bidirectional long short-term memory network learns the nonlinear residuals. For cross-battery adaptation, Ridge coefficients are transferred through prior-regularized regression, and the pre-trained network is fine-tuned using limited target-domain data. The method is validated on cycling datasets from three institutions, namely Tsinghua University, the University of Oxford, and Tongji University, covering 15 batteries under temperatures up to 50 °C. Four health-related features are extracted and adaptively denoised using locally weighted scatterplot smoothing. In single-battery extrapolation, the proposed method achieves a root mean square error as low as 0.0009 on cell B6 at 50 °C, outperforming random forest, long short-term memory, bidirectional long short-term memory, and Ridge regression by 91.1%, 88.6%, 87.7%, and 82.0%, respectively. A cross-battery ablation experiment showed that the dual-level transfer learning strategy reduced the root mean square error from approximately 0.009 to 0.0028, whereas increasing network complexity alone yielded only marginal improvement. A further hierarchical ablation showed that jointly adapting the Ridge prior and the residual network achieved a mean RMSE of 0.004325, representing reductions of 9.39%, 4.14%, and 6.92% relative to the no-adaptation, Ridge-only adaptation, and residual-network-only adaptation configurations, respectively.
Concrete exposed to sub-zero and elevated temperatures exhibits strongly non-monotonic mechanical behavior governed by different physical mechanisms. Existing thermo-mechanical constitutive models commonly account for temperature-dependent degradation, but many are formulated for a specific temperature regime, and explicit treatment of reversible freezing-induced strengthening and irreversible high-temperature damage within a single constitutive structure remains limited. This study develops a unified thermo-elastoplastic damage model for concrete over the temperature range from -40 to 800 °C within the framework of irreversible thermodynamics. Plasticity is formulated in the effective-stress space, while compressive damage is driven by the damage energy release rate. Temperature effects are incorporated through evolution laws for compressive strength, elastic modulus, peak strain, and the shape parameters of the ascending and descending branches. Ice-induced strengthening is represented through reversible modifications of stiffness and strength thresholds, whereas high-temperature dehydration and microcracking are represented through irreversible thermal damage. The model was calibrated using published low-temperature compression data for C30-C50 concrete and complete high-temperature stress-strain curves for normal-strength concrete. The normalized curve-shape laws were subsequently assessed using high-strength concrete curves after normalization by their measured peak stress and peak strain, while selected components of the three-dimensional extension were assessed using residual HSC60 true-triaxial data. The calibrated model represented the freezing-point strength valley, sub-zero strengthening and embrittlement, non-monotonic strength evolution at intermediate temperatures, and progressive high-temperature ductilization. Complete high-temperature normal-strength concrete curves were reproduced with R2 values of 0.94-0.99, while the normalized multiaxial strength assessment yielded an average relative error of approximately 8%. These results support the internal consistency of the formulation and the limited cross-strength-grade applicability of the normalized curve-shape laws, rather than unrestricted predictive capability. Further independent experiments are required before application beyond the material, moisture, thermal-history, and loading conditions represented by the available datasets.
