<?xml version="1.0" encoding="utf-8"?>
    <rss version="2.0">
      <channel xmlns:content="http://purl.org/rss/1.0/modules/content/">
        <title>Frontiers in Materials | Structural Materials section | New and Recent Articles</title>
        <link>https://www.frontiersin.org/journals/materials/sections/structural-materials</link>
        <description>RSS Feed for Structural Materials section in the Frontiers in Materials journal | New and Recent Articles</description>
        <language>en-us</language>
        <generator>Frontiers Feed Generator,version:1</generator>
        <pubDate>2026-11-15T06:50:56.860+00:00</pubDate>
        <ttl>60</ttl>
        <item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.2002723</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.2002723</link>
        <title><![CDATA[Field-evaluated constitutive modeling of Nanning silty clay for excavation above existing metro tunnels: implications for resource-efficient design]]></title>
        <pubdate>2026-11-12T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Linhai Lv</author><author>Zhe Zhao</author><author>Zhendong Zhang</author><author>Xiao Chen</author><author>Shizheng Qiu</author><author>Mingjie Jiang</author><author>Guoxiong Mei</author>
        <description><![CDATA[Reliable prediction of soil and structural deformation is important not only for safety but also for resource-efficient underground construction. Excessively conservative constitutive modeling may lead to unnecessary use of retaining, bracing, and cementitious ground-improvement materials, whereas underestimated deformation can result in infrastructure damage and resource-intensive remediation. In this study, parameters for the Modified Cam-Clay (MCC), Hardening Soil (HS), and Hardening Soil with small-strain stiffness (HSS) models were determined for silty clay sampled at the investigated site in Nanning, China, using laboratory tests on undisturbed samples, in situ shear-wave velocity measurements, and empirical correlations. The three parameter sets were then implemented in PLAXIS 2D to simulate a representative excavation section above existing twin metro tunnels, and the calculated responses were compared with field monitoring data. The MCC and HS models reproduced the overall deformation patterns of the retaining system and tunnels but systematically overpredicted tunnel heave. The HSS model provided closer predictions of tunnel vertical displacement and central-column rebound than the MCC and HS models at the final excavation stage, although the agreement varied with monitoring location and excavation stage. For tunnel sidewall displacement, however, the HSS model tended to underestimate deformation near the central column, whereas the HS model showed better local agreement. These findings suggest that accounting for small-strain stiffness and adopting site-specific constitutive parameters may help reduce overprediction of excavation-induced rebound in the investigated case. The field-evaluated parameter sets provide a modeling basis for safer excavation design and may support more rational use of retaining, bracing, and ground-improvement measures, although the associated material and environmental benefits were not directly quantified in this study.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.2012097</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.2012097</link>
        <title><![CDATA[Decoupled pre-freeze properties and earlier freeze–thaw deterioration in RDP–defoamer-modified joint-filling mortar]]></title>
        <pubdate>2026-11-11T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Wenjie Xiao</author><author>Xiaozhang Wang</author><author>Cheng Qian</author><author>Leilei Han</author>
        <description><![CDATA[Redispersible polymer powder (RDP) and defoamers are widely used to tune the workability and hardened response of cementitious mortars, but favorable pre-freeze indicators do not necessarily translate into freeze–thaw durability. This study examined a polypropylene-fiber-reinforced joint-filling mortar for prefabricated pavement bases using reference (REF), RDP-modified (RDP), defoamer-modified (DF), and combined RDP–defoamer (RDP–DF) formulations, with a commercial grout as an external benchmark. The primary comparison was between RDP and RDP–DF: both mixtures contained 280 kg m-3 mixing water and differed by the incorporation of 0.15% defoamer by binder mass. Pre-freeze mechanical, transport, and volume-stability responses were characterized, followed by longitudinal freeze–thaw tracking using mass loss and relative dynamic elastic modulus (RDEM) and by residual mechanical evaluation. Relative to RDP, RDP–DF reduced water absorption and 28-day drying shrinkage by 46.0% and 50.0%, while secant modulus increased by approximately 23%. Flexural and compressive strengths decreased by 28.8% and 25.4%, and permeability did not improve. After 15 freeze–thaw cycles, mass loss increased from approximately 0% to 5.48% and RDEM decreased from 83.94% to 64.59%. The median first observed cycle at which mass loss reached or exceeded 5% decreased from 50 to 15 cycles. In an independent 15-cycle batch, post-freeze–thaw compressive strength was 23.8 MPa for RDP and 17.2 MPa for RDP–DF, a difference of −27.7%. For similar RDP-modified joint-filling mortars, the results support combining pre-freeze properties with deterioration trajectories and residual mechanical capacity when assessing freeze–thaw durability.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1972351</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1972351</link>
        <title><![CDATA[Waste tire rubber powder enhances Asphalt’s low-temperature performance and viscoelastic temperature interval as revealed by dynamic mechanical thermal analysis]]></title>
        <pubdate>2026-11-05T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Baocai Gao</author><author>Yanzhu Wang</author><author>Zhen Liu</author><author>Guangyong Wang</author><author>Qi Liu</author><author>Xufeng Wang</author>
        <description><![CDATA[Asphalt, a typical viscoelastic material, significantly affects the performance of asphalt mixtures. Dynamic mechanical thermal analysis (DMTA) is employed to examine the viscoelastic properties of asphalt and investigate the effects of heating rate and loading frequency on its phase-transition characteristics. The dynamic mechanical response curves and characteristic temperatures of asphalt are determined, providing a basis for evaluating its properties. The results show that the temperature spectrum of mechanical response parameters and the phase-transition temperature (PTT) shift to higher temperatures with increasing heating rates and loading frequencies. Heating rate and the logarithmic value of loading frequency exhibit a linear relationship with the phase-transition temperature. A three-dimensional spatial relationship model is established to predict the PTT under various test conditions. T1, T0, and Tg are used as dynamic indicators of low-temperature performance, and their ranking is consistent with BBR results. Adding SBS or waste tire rubber powder modifiers improves the low-temperature performance of neat asphalt, with rubber asphalt demonstrating superior performance compared to SBS-modified asphalt. This highlights the potential of using waste tire rubber as a value-added modifier in eco-friendly asphalt materials. For high-temperature performance evaluation, neat asphalt and modified asphalt require separate analysis based on T2. The viscoelastic temperature interval (VTI) provides a phase-transition-based candidate service temperature interval for asphalt. Incorporating SBS modifiers or rubber powder into neat asphalt effectively broadened the viscoelastic temperature interval, with rubber asphalt exhibiting the widest VTI.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1991878</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1991878</link>
        <title><![CDATA[Interfacial interactions between crumb rubber-polyphosphoric acid composite-modified asphalt and aggregates]]></title>
        <pubdate>2026-11-05T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Qi Li</author><author>Juan Li</author><author>Guangguo Wu</author><author>Tangxin Xie</author><author>Yuchen Wang</author>
        <description><![CDATA[Waste crumb rubber and polyphosphoric acid (PPA) were incorporated into asphalt mastic through a staged shearing process under controlled temperatures. Their combined effects were examined using a cross-scale framework that linked surface free-energy measurements, atomic force microscopy, rheological sweeps, and pull-off tests. The combined use of crumb rubber and PPA shifted the asphalt colloidal system from a sol-like state toward a more interconnected gel structure. This transition increased surface roughness, promoted microscale mechanical interlocking, and restrained interfacial slippage. The anti-stripping agent further improved interfacial wetting and polar compatibility, while the fibers supported the mastic skeleton and maintained continuous stress transfer within the material. CRA-PPA-2, containing crumb rubber, PPA, an anti-stripping agent, and lignin fibers, achieved dry pull-off tensile strength (POTS) values of 2.76 and 2.86 MPa and wet POTS values of 2.29 and 2.43 MPa for basalt and diabase, respectively. The corresponding pull-off strength retention ratios (TSR) reached 83.0% and 85.0%, indicating improved resistance to moisture-induced bond deterioration. This combined modification approach effectively alleviated water-induced adhesion loss and interfacial debonding, offering a practical strategy for improving the interfacial durability of asphalt pavements.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1934520</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1934520</link>
        <title><![CDATA[Weak-phase competition and damage redistribution in shale ceramsite–basalt mixed-aggregate concrete: experimental observations and discrete element simulations]]></title>
        <pubdate>2026-11-02T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Luyuan Yan</author><author>Weiyu Xu</author><author>Yiding Liu</author><author>Yang Liu</author><author>Hongwu Gao</author>
        <description><![CDATA[The compressive failure of shale ceramsite–basalt mixed-aggregate concrete involves competition among matrix cracking, interfacial bond breakage, and intra-aggregate fracture. This study combines experimental peak responses and representative fracture observations for concrete with shale ceramsite replacement ratios of 0%, 25%, 50%, 75%, and 100% with calibrated two-dimensional discrete element method (DEM) analyses. Mortar, shale ceramsite, and basalt were represented as distinct material phases, and five contact categories were distinguished to track phase-specific bond breakage. The absolute relative deviations between the experimental calibration targets and simulated peak compressive stresses were 0.04%–1.38%, whereas the corresponding peak-strain deviations were 2.38%–14.66%. At the simulated peak-strain state, the contribution of intra-ceramsite fracture to the cumulative bond-breakage population increased from 19.99% in C25 to 34.12% in C100, while the matrix contribution decreased from 83.78% in C0 to 57.40% in C100 but remained the largest single contribution. Coupled enhancement of the ITZ parameters from 0.1 to 0.2 of the corresponding mortar values increased peak compressive stress by 34.87%, 28.31%, and 18.14% for C0, C50, and C100, respectively, with generally smaller additional gains at higher ratios. Increasing intra-aggregate cohesion and tensile strength to 300% of the baseline values increased peak stress by approximately 0.65% for C0 but by 18.01% for C100. These results indicate a composition- and resistance-dependent redistribution of phase participation rather than a discrete transfer of failure control among individual phases. The findings provide a mesoscale interpretation of damage competition within the investigated mixtures and calibrated two-dimensional numerical framework.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1967566</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1967566</link>
        <title><![CDATA[Corn straw fiber-modified asphalt for high-RAP recycled PAC-13 mixtures: preparation, rheology, and pavement performance]]></title>
        <pubdate>2026-10-30T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Fengqiang Sun</author><author>Yanzhu Wang</author><author>Lingbo Liu</author><author>Fengchun Zhang</author><author>Chang Wang</author><author>Wenjuan Wu</author>
        <description><![CDATA[IntroductionOpen burning of corn stalks causes environmental pollution, while recycled asphalt mixtures with high reclaimed asphalt pavement (RAP) content require adequate binder performance to maintain pavement durability. This study evaluated corn stalk fibers as bio-based modifiers for high-RAP recycled PAC-13 mixtures.MethodsCorn stalk fibers were prepared using physical-mechanical and chemical alkali treatments, and treatment conditions were evaluated using Fourier-transform infrared spectroscopy and thermogravimetric analysis. Asphalt binders containing 0.4%–2.0% fiber were tested using a dynamic shear rheometer and a bending beam rheometer. The selected binder was used to prepare recycled PAC-13 mixtures containing 20%–60% RAP, and their pavement performance was assessed.ResultsChemical alkali treatment with 3% NaOH for 50 min produced fibers with superior thermal stability and oil absorption capacity. The optimal fiber content was 1.2%, improving the binder’s high-temperature shear resistance and low-temperature stress relaxation. As RAP content increased, optimum binder content, Marshall stability, dynamic stability, moisture resistance, and low-temperature crack resistance declined, while air void content increased. At approximately 40% RAP, all key performance indicators met the relevant technical specifications.DiscussionUnder the materials and experimental conditions investigated, approximately 40% RAP is the recommended upper limit for corn stalk fiber-modified recycled PAC-13 mixtures.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1987666</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1987666</link>
        <title><![CDATA[Rheological performance and modification mechanism of corn stover oil/polyphosphoric acid composite-modified asphalt]]></title>
        <pubdate>2026-10-30T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Chenglin Du</author><author>Biao Shu</author><author>Qing Wang</author><author>Wen Nie</author><author>Xinxian Li</author><author>Bo Chen</author>
        <description><![CDATA[To improve the high-temperature performance of corn stover oil (CSO) bio-asphalt and facilitate biomass utilization, polyphosphoric acid (PPA) was introduced to prepare CSO/PPA composite binders with different modifier combinations. The binder properties were evaluated through conventional tests, temperature sweep (TS), multiple stress creep recovery (MSCR), bending beam rheometer (BBR), and Fourier-transform infrared spectroscopy (FTIR). Two-factor ANOVA identified significant CSO × PPA interactions in penetration, viscosity at 135 °C, and MSCR responses, with the strongest effect observed for Jnr,3.2 (partial η2 = 0.795), while no significant interaction was found for G*/sin δ or BBR parameters. PPA improved stiffness-related properties and high-temperature deformation resistance by increasing the softening point, viscosity, rutting parameter, and MSCR recovery, while decreasing non-recoverable creep compliance; however, excessive PPA increased low-temperature stiffness and reduced the m-value. CSO showed a pronounced softening and plasticizing effect, improving low-temperature ductility and stress-relaxation capacity at the expense of high-temperature stability. Considering the conventional, TS, MSCR, and BBR results together, a PPA dosage of 3%–4.5% is recommended when the CSO content is 8%, whereas 4.5% PPA is recommended when the CSO content is 10%. FTIR spectra showed phosphorus-related absorption features near 1150 and 1002 cm-1 after PPA addition and a new feature near 1709 cm-1 after CSO incorporation, indicating composition-related changes in characteristic functional groups.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1984896</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1984896</link>
        <title><![CDATA[Fly ash replacement and sand-to-binder ratio shape trade-offs among workability, strength, and stiffness in joint-filling mortar]]></title>
        <pubdate>2026-10-30T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Zhengxin Wu</author><author>Bing Han</author><author>Zhiqing Zhu</author><author>Leilei Han</author>
        <description><![CDATA[IntroductionJoint-filling mortars must retain placement mobility while developing adequate load-bearing capacity without excessive stiffness.MethodsA 5 × 3 full-grid experiment was conducted using 40%–60% fly ash (FA) replacement, sand-to-binder ratio (S/B) of 0.35–0.55, a fixed water-to-binder ratio (W/B) of 0.30, and polypropylene (PP) fiber at 2.0 vol.% of total mortar volume. Strength and 28-d compressive secant modulus were evaluated using nested empirical regression models with leave-one-mixture-out cross-validation, while a targeted three-block randomized complete block design (RCBD) with a fixed high-range water reducer (HRWR) dosage was used to validate the principal FA and S/B response gradients and to support three-objective Pareto screening.ResultsAcross the full grid, increasing FA from 40% to 60% reduced mean 28-d compressive strength and secant modulus by 10.28 MPa and 5.0 GPa, respectively. At FA = 60% under fixed HRWR, increasing S/B from 0.45 to 0.50 reduced free spread by 7.17 mm while increasing 28-d compressive strength by 5.20 MPa, with no resolved modulus change; the subsequent increase to 0.55 reduced free spread by 20.50 mm, decreased 28-d compressive strength by 2.53 MPa, and increased modulus by 1.92 GPa. Strength development remained age dependent, with the 60% FA group showing the largest ratio of group-mean 28-d to 7-d compressive strengths in the full-grid dataset. Pareto screening of the five fixed-HRWR validation mixtures identified M9, M10, M11, and M12 as non-dominated alternatives.DiscussionWithin the tested material and processing window, equal S/B increments therefore did not retain the same marginal response, and the non-dominated mixtures represent application-dependent trade-off options among workability, strength, and stiffness.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1961699</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1961699</link>
        <title><![CDATA[Machine-learning ultrasonic detection of fatigue cracks: a physics-based simulation study]]></title>
        <pubdate>2026-10-28T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Shicheng Hu</author><author>Shuo Chen</author><author>Caifeng Wang</author>
        <description><![CDATA[Fatigue cracks in microtextured titanium alloys are hard to find by ultrasound. Backscatter from alpha colonies, modulated by microtextured regions, mimics a small flaw, and crack faces held in contact by residual stress reflect far less energy than their area suggests. This paper is a simulation study. It builds a forward model of pulse-echo inspection whose constants are those of mill-annealed Ti-6Al-4V, verified against closed-form solutions on 15 quantities, and uses it to characterise what a learned detector can and cannot deliver under that model. The model solves a bilinear contact law at the crack interface, coupling the linear and nonlinear scattering paths. The detector reads the drive and second-harmonic bands through a small dilated residual encoder trained on simulated records only, and converts the score into a decision by split conformal calibration, whose false-call guarantee holds under exchangeability and is not claimed under distribution shift. On simulated test specimens with crack half-lengths from 0.05 to 1.0 mm, the encoder calls 73 of 84 low-contact cracks with no false call on 180 defect-free specimens (95% upper bound 0.017), and its fitted half-length at 90% detection is 0.138 mm (bootstrap interval 0.088–0.181 mm). A second-harmonic peak with no learning has the highest part-level area under the curve, the four leading methods are not separable on that measure, and an input ablation shows that an encoder reading the second-harmonic envelope alone matches or exceeds the full model, so the harmonic band carries the performance; over five training seeds the low-contact detection count spans 73 to 82 of 84. The encoder adds decision efficiency at the operating point, nine additional low-contact detections against one lost relative to the harmonic peak (paired test p=0.02), not information absent from the measurement. Detection is confined to contact fractions between 0.05 and 0.30. The decision layer alone is then applied, as a methodological case study, to measured guided-wave data from an aluminium plate cycled to 100,000 cycles, where the second-harmonic channel gives 4 false calls in 370 angle tests and the drive band 9. No experimental validation on Ti-6Al-4V or on any other titanium alloy is presented, the only measured data are aluminium, and no qualification is claimed.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1985464</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1985464</link>
        <title><![CDATA[Nonlinear evolution and influencing mechanism of rutting in asphalt pavement under coupled high-temperature and heavy-load conditions]]></title>
        <pubdate>2026-10-27T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Rui Deng</author><author>Jincheng Wei</author><author>Haihui Li</author><author>Lei Niu</author><author>Long Chen</author><author>Wenyang Han</author><author>Mingxing Qin</author><author>Sijin Wei</author>
        <description><![CDATA[To investigate the nonlinear evolution and mechanism of rutting in asphalt pavement incorporating steel slag under coupled high-temperature and heavy-load conditions, a three-dimensional finite element model was established in ABAQUS based on a typical semi-rigid base asphalt pavement structure. Steel slag was used to replace 30% of the natural coarse aggregate by mass. The Bailey–Norton creep model was adopted to characterize the high-temperature mechanical behavior of the asphalt mixtures, and the model was validated using laboratory rutting tests. On this basis, coupled working conditions involving multiple temperatures and load levels were established. The rut depth at 60 min was used as the primary evaluation index, and a coupling influence coefficient was introduced to quantitatively characterize the interaction between temperature and contact pressure. The results show that rut depth increased nonlinearly with increasing temperature and contact pressure. The coupling influence coefficient remained close to unity under a contact pressure of 1.0 MPa, whereas it increased to 1.09 and 1.15 at 65 °C and 70 °C, respectively, under 1.2 MPa, indicating an evident synergistic amplification under severe high-temperature and heavy-load conditions. Mechanistic analysis indicates that high temperature reduces the modulus and shear resistance of the asphalt mixtures, while heavy loading increases the internal stress level. Their combined action increases the shear stress ratio and promotes the accumulation of shear-related viscoplastic deformation. The AC-20 layer remained the main contributor to rutting, while the contribution of AC-13 increased with temperature. The findings provide a reference for the rutting performance evaluation and pavement design of asphalt mixtures incorporating steel slag under high-temperature and heavy-traffic conditions.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1879093</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1879093</link>
        <title><![CDATA[Forest-residue-derived constituents for low-carbon cementitious materials: evidence boundaries, quantitative trade-offs, and cold-region service qualification]]></title>
        <pubdate>2026-10-26T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Wenbo Fan</author><author>Chenyun Tao</author><author>Shouheng Jiang</author><author>Meng Zang</author><author>Yini Tan</author>
        <description><![CDATA[Forest-residue-derived constituents are increasingly being considered for low-carbon cementitious materials, but their functions differ substantially and should not be treated as a single waste-substitution category. Wood ash may serve as a screened supplementary cementitious material or mineral filler, wood-derived biochar mainly modifies hydration and pore-water behavior at low dosage, and wood fiber acts primarily as crack-control reinforcement. This review compares these three material classes through their source-specific characteristics, quantitative performance ranges, and governing microstructural mechanisms. Direct evidence from wood-derived constituents is distinguished from mechanistic analog evidence from non-wood biomass ashes and lignocellulosic fibers. Published studies commonly examine wood ash at approximately 5%–20% cement replacement and biochar at low dosages, often at approximately 0.5–3 wt% of binder, while wood and related lignocellulosic fibers are generally used at low volume fractions. These ranges are screening values rather than universal design limits because performance depends strongly on processing, water demand, dispersion, interfacial behavior, and mixture composition. Cold-region exposure is considered a demanding service-qualification case rather than as a separate material theme. Freeze–thaw, salt exposure, and chloride transport are used to assess whether changes in pore-water distribution, air-void stability, interfaces, and crack connectivity remain beneficial under severe service conditions. The review concludes with a staged route from constituent characterization and mixture screening to mechanism verification, exposure-relevant testing, and field validation.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1950801</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1950801</link>
        <title><![CDATA[EPD-grounded carbon-resilience allocation for low-carbon concrete supply: decision fidelity, route validation, and correlated-disruption stress testing]]></title>
        <pubdate>2026-10-22T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Xin Yang</author><author>Yong Xiang</author><author>Yao Wei</author>
        <description><![CDATA[IntroductionGreen construction teams need a defensible way to convert product-specific concrete carbon declarations into supply decisions that recognize delivery and disruption exposure. Prediction-to-optimization workflows can obscure a critical evidence boundary: verified environmental product declaration (EPD) values can support formal supplier comparison, whereas machine-learning estimates require decision-level validation before allocation.Methods We introduce an evidence-aligned framework that separates observed EPD attributes, model-estimated screening outputs, scenario-derived A4 transport, and assumption-based disruption stress and assigns each a specific decision role. Model transportability was audited using plant, company, temporal, and geographic holdouts, followed by a direct comparison of predicted and EPD-observed rankings and allocations. Formal strength-constrained optimization minimized observed EPD A1–A3 plus scenario A4 under plant-share caps.ResultsAfter harmonization and deduplication, the analysis contained 45,739 EPD records from 663 plants. A prospective external cohort added 22 declarations from 14 plants and seven derivation-unseen companies; the frozen model reduced record-level MAE by 6.6% relative to the frozen training median, while the supplier-ranking gate retained the EPD-grounded path. Across nine city-strength cases, a 40% cap produced three-plant allocations with a mean Herfindahl–Hirschman Index of 0.36. Under a 10% independent plant-disruption stress rate, it reduced the probability of losing at least half of supply from 0.100 to 0.027; mean and median A1–A4 premiums were 14.57% and 7.76%, respectively. The benefits remained measurable across disruption probabilities of 5%–30% and pairwise correlations of 0–0.50. An OpenStreetMap routing check covered 79 plant–project pairs: median distance error was 6.39%, 17 of 18 allocation decisions were unchanged, and the remaining case had 0.026% route-evaluated objective regret.DiscussionThe contribution is a transparent carbon-concentration frontier with an empirical decision-fidelity gate: prediction supports early screening, whereas EPD values anchor formal allocation. The framework provides extensible planning evidence while preserving clear boundaries between comparative scenarios and operational procurement.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1954367</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1954367</link>
        <title><![CDATA[Mechanical behaviors of weathered coal gangue filled concrete pavement based on surface solidification]]></title>
        <pubdate>2026-10-21T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Yingsong Li</author><author>Wei Guo</author><author>Xinge Miao</author><author>Xiangling Tao</author><author>Qingtao Wang</author><author>Jiangyi Zhang</author><author>Weichi Chen</author><author>Ziyao Wei</author>
        <description><![CDATA[Weathered coal gangue (WCG) is a solid waste formed by the long-term accumulation and weathering of coal gangue. Its low strength and poor stability prevent direct use as a concrete aggregate, limiting large-scale utilization. To overcome this, a consolidation treatment was developed and the treated WCG was evaluated as a replacement aggregate for concrete pavement in mining areas. The physical properties of the WCG before and after treatment were first measured. Then, the failure modes and stress changes of WCG concrete under different replacement intervals were evaluated by compressive strength, splitting tensile strength, flexural strength, shear strength tests and numerical simulation. The results showed that the Los Angeles wear rate, Vickers hardness and impact value of WCG after consolidation treatment were 19.88%, 141.43 kgf/mm2 and 5.66%, respectively, indicating improved wear resistance, hardness, and impact resistance after consolidation treatment. Under the condition of meeting the requirements of secondary road strength, the maximum substitution range of WCG replacement gravel was 2.36–19.0 mm. At this time, the flexural strength of concrete was 4.67 MPa, the compressive strength was 27.81 MPa, the splitting tensile strength was 2.13 MPa, the cohesion was 2.93 MPa, and the internal friction angle was 66.20°. The simulation results showed that the failure mode was of the ‘X’ type when no aggregate was replaced by coal gangue, whereas after full replacement the failure initiated at the outermost large aggregate and propagated inward, with the cracks propagating along the interfacial transition zone (ITZ) and through the aggregate. When the replacement interval was 2.36–19.0 mm, the interval contributing most to the stress bearing capacity of WCG concrete was 19.0–31.5 mm, with a contribution rate of 58.31%. These findings provide a theoretical basis for the application of WCG in concrete pavement.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1978854</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1978854</link>
        <title><![CDATA[Performance enhancement of concrete with alkali-conditioned fly ash lightweight aggregate]]></title>
        <pubdate>2026-10-21T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Xiaozhong Zheng</author><author>Tao Han</author><author>Zhuang Wang</author><author>Tingting Luo</author><author>Guangfei Liu</author><author>Bing Xue</author><author>Peihe Yu</author><author>Yongsheng Ji</author>
        <description><![CDATA[Lightweight concrete serves as an effective means of minimizing the dead load of shaft walls. In the present work, spherical lightweight aggregates produced from fly ash were employed as a substitute for conventional sand and gravel in wellbore concrete mixtures. A series of alkaline immersion curing experiments and material characterization tests were carried out to evaluate the effects of alkali type and concentration on the fundamental properties of non-sintered fly ash lightweight aggregates, including unconfined compressive strength and water resistance. The investigation also examined how aggregate grading and water-to-cement ratio influence the mechanical behavior and impermeability of fly-ash lightweight aggregate concrete. Scanning electron microscopy combined with microhardness testing was utilized to characterize the modifications in the interfacial transition zone induced by alkaline curing. A mechanistic model was proposed to explain the improvements in mechanical properties and impermeability under alkali treatment. Experimental results demonstrate that alkaline immersion promotes more complete hydration of fly ash, thereby directly enhancing both the unconfined compressive strength and impermeability of FLBA concrete. In alkali-activated FLBA concrete, the microhardness across the ITZ is considerably higher than that of the bulk cement paste matrix; the microhardness values increase as the aggregate surface is approached, and this gradient exhibits a strong correlation with the degree of improvement in mechanical strength and impermeability.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1947456</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1947456</link>
        <title><![CDATA[Non-linear analysis of composite steel-concrete beam with web openings using finite element method and design of experiments]]></title>
        <pubdate>2026-10-14T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Mastan Sheik</author><author>M. Vishnu Priyan</author><author>Ramesh Kothapali</author><author>S. Aishwarya</author>
        <description><![CDATA[In structural engineering, composite beams with web openings are essential for accommodating ducts and pipes while maintaining floor-to-floor height. However, web openings can reduce the load-carrying capacity and alter the structural response of composite beams. This study investigates the effects of web-opening shape, opening area, and spacing-to-diameter ratio on the structural behaviour of composite steel–concrete beams using nonlinear finite element analysis and design of experiments. Five opening shapes, three opening areas of 7,853, 31,415, and 125,663 mm2, and spacing-to-diameter ratios ranging from 1.08 to 3 were investigated using ABAQUS v6.14, resulting in a total of 330 finite element models. The finite element results were analysed using a design of experiments framework with an L27 orthogonal array, response surface methodology, and analysis of variance using MINITAB 20 and Design-Expert 13. The results showed that circular openings exhibited the highest load-bearing capacity among the investigated opening shapes, while opening area and spacing-to-diameter ratio were the dominant parameters influencing the ultimate load. The response-surface analysis identified an opening area of 31,415 mm2 and a spacing-to-diameter ratio of 1.50 as the highest-response combination within the investigated parameter range. The findings demonstrate the added value of integrating validated nonlinear finite element modelling with DOE-based response surface analysis to systematically evaluate and optimise web-opening configurations in composite steel–concrete beams.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1967974</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1967974</link>
        <title><![CDATA[Mesoscopic crack evolution and cracking resistance of recycled asphalt mixtures with different RAP contents using discrete element method]]></title>
        <pubdate>2026-10-13T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Hao Li</author><author>Haiqi Zhang</author><author>Yimin Huang</author><author>Qiuwei Liu</author><author>Jiumou Zhan</author><author>Yongkang Lin</author>
        <description><![CDATA[To reveal the mesoscopic mechanism underlying the deterioration of macroscopic cracking resistance in recycled asphalt mixtures, this study constructed discrete element models that finely characterize virgin aggregates, RAP, aged asphalt, and new asphalt binder, while considering aggregate breakage and aged asphalt coating layers of different thicknesses. The mesoscopic parameters are calibrated using indoor splitting test results. On this basis, the influence of RAP content on mesostructural damage and cracking behavior of the mixtures was investigated, and quantitative relationships between mesoscopic damage indicators and macroscopic mechanical properties were established. The results indicate that microcracks preferentially initiate in the loading axis region, while the lateral regions experience lower stresses and serve as buffer zones. The splitting failure is essentially a tensile failure induced by tensile stress exceeding the material limit, with tensile microcracks accounting for more than 97% of the total. As the RAP content increases from 15% to 60%, the crack development pattern gradually evolves from a linear primary crack to branch-like and eventually network-like propagation. Aggregate breakage is mainly concentrated at the two ends of the loading axis and along the crack propagation paths, with the total breakage index ranging from 4% to 10%. A clear negative correlation exists between mesoscopic damage indicators and macroscopic mechanical responses. Mesoscopic damage ultimately leads to the degradation of macroscopic performance through two pathways, namely, microcrack coalescence and skeleton weakening. The findings of this study can provide a theoretical basis for the design optimization of recycled asphalt mixtures.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1979048</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1979048</link>
        <title><![CDATA[Characteristics of fume components and dynamic emission behavior of crumb-rubber-modified asphalt]]></title>
        <pubdate>2026-10-09T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Liaoliang Luo</author><author>Jiasheng Dai</author><author>Wenqiang Zhu</author><author>Changfeng Li</author><author>Long Yu</author><author>Yu Liu</author><author>Binqian Li</author><author>Zhenghao Zhang</author>
        <description><![CDATA[IntroductionCrumb-rubber-modified asphalt (CRMA) facilitates the recycling of end-of-life tires but may release complex fumes during high-temperature processing. This study characterized the dynamic fume evolution and representative organic components of CRMA.MethodsAn integrated system combining controlled fume generation, real-time monitoring, and offline collection was developed. Volatile organic compound (VOC) responses from four asphalt binders were monitored at 120–200 °C. The H₂S and SO₂ responses of CRMA were quantified, and the detectable organic components in fumes from CRMA and its corresponding base asphalt were analyzed using gas chromatography–mass spectrometry.ResultsThe VOC concentration–time profiles were reproducible, with relative deviations below 10% during the principal response stages. VOC responses increased with temperature, generally peaking before gradually approaching a slowly varying stage. At 200 °C, the peak VOC concentration of CRMA reached 3,719.1 mg/m³, approximately 5.5 times that of the base asphalt. As the temperature increased from 120 to 200 °C, the cumulative responses of H₂S and SO₂ increased from 265 to 1,035 ppm·min and from 3,785 to 5,715 ppm·min, respectively. CRMA also exhibited more resolved chromatographic peaks, with isoprene-related compounds, benzothiazole derivatives, benzothiophene, and dibenzothiophene forming representative crumb-rubber-associated signals.DiscussionElevated temperatures intensified CRMA fume responses through the combined effects of volatilization, enhanced thermal desorption of rubber-bound components, and mass transfer, providing a basis for processing-temperature optimization and targeted fume control. The reported concentrations are laboratory-specific sensor-equivalent values intended for comparative assessment rather than direct estimation of field emissions or occupational exposure.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1930537</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1930537</link>
        <title><![CDATA[Study on the influence of matrix asphalt mixture air voids on the performance of semi-flexible pavement materials]]></title>
        <pubdate>2026-10-09T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Jie Chen</author><author>Zhiyu Yang</author><author>Hui Huang</author><author>Jiechao Lei</author><author>Weian Xuan</author>
        <description><![CDATA[In practical applications, semi-flexible pavement materials need to achieve a balance between mechanical properties, high-temperature stability, cracking resistance, and water stability. However, these performance requirements are strongly influenced by the void content of the matrix asphalt mixture, which determines the grouting space and the composite structure of semi-flexible pavement materials. In this study, matrix asphalt mixtures with three different void contents (20.6%, 24.9%, and 29.2%) were prepared. The effects of the matrix void content on the perfusion characteristics and overall performance of semi-flexible pavement materials were systematically evaluated through perfusion tests, Marshall stability and splitting tests, three-point bending tests, rutting tests, and freeze–thaw splitting tests. Subsequently, the impact of the void ratio on each parameter was analyzed. The findings indicate that, within the tested void content range (20.6%–29.2%), increasing the void ratio of the matrix asphalt mixture continuously improved the mechanical properties of the semi-flexible pavement material: the Marshall stability was enhanced by a factor of up to 4.8, and the splitting strength by up to 1.4 times. Results from the trabecular three-point bending test reveal a more pronounced effect of void fraction on the crack resistance of semi-flexible pavement materials with rising temperatures. At 15 °C, lower void fractions lead to superior crack resistance. Conversely, when the void fraction reaches 24.9% at −10 °C, semi-flexible pavement materials exhibit enhanced crack resistance. Rut dynamic stability and freeze–thaw splitting tests demonstrate that higher void ratios in the matrix correlate with superior resistance to high-temperature deformation and water stability. When the void ratio falls below 24.9%, increasing it significantly enhances resistance to high-temperature deformation, with an improvement range of up to 63.6%. Therefore, 24.9% is identified as the recommended balanced air-void content of the matrix asphalt mixture, at which the semi-flexible pavement material achieves the most balanced comprehensive performance in terms of mechanical properties, high-temperature deformation resistance, water stability, and cracking resistance.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1957042</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1957042</link>
        <title><![CDATA[Sustainable valorization of phosphogypsum solid waste as composite filler in asphalt mastic: rheological behavior and construction benefits]]></title>
        <pubdate>2026-10-08T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Liangchao Li</author><author>Baoan Li</author><author>Lu Yang</author><author>Xingjun Liu</author><author>Xinran Gu</author><author>Haowen Li</author><author>Yixiang Li</author><author>Jiufu Yang</author><author>Wenju Peng</author>
        <description><![CDATA[Massive phosphogypsum (PG) stockpiles bring persistent environmental risks in China, while heavy-duty channelized traffic increasingly causes premature rutting and fatigue cracking in asphalt pavements. To reconcile engineering requirements with environmental pressures, PG was used as a filler for high-value applications. In this study, asphalt mastic was prepared using Grade A 70# road asphalt, with mineral powder and PG as a single filler, and a PG–mineral powder composite filler. Temperature–frequency scanning, multiple stress creep recovery (MSCR), and linear amplitude scanning (LAS) tests were subsequently conducted using a dynamic shear rheometer (DSR). The influence of filler type, filler–asphalt ratio, and blend proportions on the mechanism of viscoelastic behavior evolution in mastic was analyzed. It was found that PG filler enhanced the high-temperature deformation resistance of asphalt mastic compared with mineral powder. At high filler–asphalt ratios, the transition of the viscoelastic structure could be delayed, and weak shear thickening characteristics were exhibited under heavy shear loading. A filler–asphalt ratio threshold was observed for the fatigue resistance of PG mastic. At a filler–asphalt ratio of 1.0, its fatigue life was found to surpass that of mastic with mineral powder. For the composite system, a performance-to-blend-ratio threshold was demonstrated. At a 50% PG blend ratio (filler–asphalt ratio was 1.0), optimal fatigue resistance was achieved while maintaining excellent high-temperature stability. Furthermore, a quantitative assessment confirmed that this optimal blend reduces filler processing carbon emissions by 42.9%. These findings provide core theoretical support and key design parameters for the sustainable, large-scale application of PG solid waste in green highway construction.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/fmats.2026.1973453</guid>
        <link>https://www.frontiersin.org/articles/10.3389/fmats.2026.1973453</link>
        <title><![CDATA[Hydration, mechanical, and environmental performance of blended cements incorporating ground granulated blast furnace slag, ground waste bottle glass, and metakaolin]]></title>
        <pubdate>2026-10-08T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Saule Mergenbayeva</author><author>Nuray Abdullayeva</author><author>Aliya Abzal</author><author>Kassym Talgatuly</author><author>John L. Provis</author><author>Chang-Seon Shon</author><author>Zhanar Zhakiyeva</author>
        <description><![CDATA[This study investigates the effect of incorporating 20 wt% ground granulated blast furnace slag (GGBFS), ground waste bottle glass (GWBG) and metakaolin (MK) on the hydration behavior, mechanical and environmental performance of blended cements cured at 23 °C ± 2 °C for 7, 28, and 90 days. Mechanical performance was evaluated using the strength activity index (SAI), while environmental performance was assessed through heavy metal leaching and a preliminary sustainability screening. The tested mortars achieved SAI values greater than 80% at all curing ages, consistent with the observed development of hydration products and microstructural evolution. Heavy metal leaching tests showed Pb and Zn below the limit of detection, while Cr release ranged from 0.70 to 1.15 mg/kg, which is substantially below the non-hazardous waste acceptance limit. The preliminary sustainability screening showed reductions of 10.9%–17.2% in calculated binder-production embodied energy and 12.9%–18.9% in calculated binder-production CO2 emissions compared to a plain Portland cement benchmark. These findings demonstrate the potential of these SCMs for producing blended cements with satisfactory mechanical performance, limited trace-metal release, and lower calculated binder-production CO2 indicators compared with the plain Portland cement benchmark.]]></description>
      </item>
      </channel>
    </rss>