Search Results (6,718)

Improving both the high- and low-temperature performance of asphalt is still difficult in modern pavement applications. This performance imbalance has motivated the development of new modification strategies that can enhance temperature stability while maintaining construction workability. In this research, a low-molecular-weight elastic polyolefin (POL) with inherent compatibility was introduced as a novel asphalt modifier. POL was incorporated at five dosages (0%, 2%, 4%, 6%, and 8% by weight of asphalt) to investigate its effects on the fundamental physical, rheological, and low-temperature properties of the asphalt. The rheological behavior was characterized by dynamic shear rheometer (DSR) and bending beam rheometer (BBR), while the modification mechanism and dispersion morphology were analyzed through Fourier-transform infrared spectroscopy (FT-IR) and fluorescence microscopy (FM). The results reveal that POL markedly improves the high-temperature performance and workability of asphalt, with the rutting factor increasing by two- to eightfold. POL modification improved the thermal stability of asphalt, shifting the maximum decomposition temperature from 455.2 °C for the base binder to 461–463 °C, while the total mass loss remained nearly constant at 80–83%. Microscopic observations confirm that POL forms a physically blended network within the asphalt matrix, exhibiting a green fluorescent structure that becomes progressively continuous with increasing dosage. The most homogeneous dispersion and optimal compatibility occur at a POL dosage of 6%, beyond which phase segregation emerges and low-temperature properties deteriorate. Accordingly, a 6% POL dosage is recommended for achieving balanced performance. These findings provide theoretical and practical guidance for the development of balanced performance and thermally stable POL-modified asphalt materials. Full article

In contemporary construction practice, concrete surfaces are commonly coated; however, this factor is often disregarded in durability assessments, particularly with respect to carbonation. Such omission may lead to overly conservative designs and unnecessary material consumption. This study evaluates the actual performance of traditional coatings applied to concrete, considering three types of concrete: ordinary Portland cement (OPC), high-volume fly ash (FA), and high-volume FA with a low water-to-binder ratio. The coatings investigated were mainly based on cement and hydrated lime, with the inclusion of a FA-based alternative. Accelerated carbonation tests were performed on coated and uncoated concretes, as well as on coating mortars, while a sensitivity analysis was undertaken using an empirical and semi-probabilistic model across different exposure classes to simulate real service conditions. The results demonstrate excellent performance, with coated concretes achieving on average more than 52% higher resistance compared with uncoated counterparts. These findings indicate that properly designed coatings can enable reductions in cement content while still satisfying durability requirements, thereby contributing to more sustainable reinforced concrete structures. Full article

The reuse of waste generated in various sectors has become a sustainable alternative. Advances in research highlight its potential as a secondary raw material to produce construction materials, contributing to the reduction in waste disposal while mitigating the intensive exploitation of natural resources. Tempered glass is rarely used in recycling and in the production of new materials. Therefore, this study evaluated the applicability of using it, after glass crushing, as a partial replacement for natural sand in the production of cement products. Thus, natural sand was replaced by 25% and 50% with sand resulting from glass crushing, and the mechanical properties (mechanical strength) and porosity (water absorption and void index) of the cementitious mixtures (mortars) were evaluated at 28 days, as well as their chemical properties and CO₂ emissions. Glass powder (a result of crushing glass) was added to the mixtures to maximize the use of residual materials and improve the performance of the composite. The results demonstrate gains of approximately 10% in the studied properties with the substitution of natural sand with crushed tempered glass sand, and above 24% for the addition of glass powder, i.e., the addition of 20% powder glass tends to contribute favorably to the performance of cementitious mixtures, supporting the production of more sustainable building materials and making it an appropriate strategy for the circular economy. Full article

This work provides a systematic experimental study for the electrochemical desalination of saline water using an electrospun permselective polyvinylidene difluoride (PVDF) membrane. Several nano additives were initially screened during membrane development; however, only the materials that demonstrated stable dispersion, reproducible membrane formation, and consistent electrochemical behaviour, namely graphene oxide (GO) and carbon nanotubes (CNTs) were selected for full analysis in this study. Accordingly, the study focuses on pure PVDF, PVDF/GO, and PVDF/CNTs membranes integrated with an alternating Ag/AgCl electrode system. The silver electrode is prepared by spray-coating of silver nanoparticles on high surface carbon cloth, whereas the AgCl electrode was prepared electrochemically from the Ag electrode using a three-electrode electrochemical cell. The electrochemical behaviour of various modified electrodes (bare carbon cloth, Ag/carbon cloth, Ag/nafion/carbon black/PVDF, and Ag/nafion/carbon cloth) was evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and X-Ray Diffraction (XRD). The electrode prepared using Nafion and PVDF as binders with carbon black as conductive additive exhibited the highest current response and lowest charge-transfer resistance. When coupled with this optimized electrode, the PVDF/GO membrane delivered the best desalination performance, achieving an ion removal efficiency of 68%, a salt adsorption capacity (SAC) of 775.40 mg/g, and a specific energy consumption (SEC) of 16.17 kJ/mole values superior to those reported in the literature. Full article

The urgent need to reduce greenhouse gas emissions and enhance resource circularity is driving the cement and construction industry to explore alternatives to clinker-based binders. Electric arc furnace slag (EAFS), a major steelmaking by-product, is currently underutilised as a binder due to its low intrinsic reactivity. This study provides a comparative evaluation of three distinct valorisation pathways for the same EAFS—use as a supplementary cementitious material (SCM), as a precursor for alkali-activated binders, and as a component in accelerated carbonation systems—thereby highlighting its multifunctional and more ecological binding potential. A comprehensive physicochemical characterisation was conducted, followed by mechanical performance assessment under different curing regimes. When used as an SCM, partial cement replacement resulted in no loss of mechanical performance and a compressive strength increase of up to 8.9% at 10% replacement, demonstrating its suitability for structural applications. Under accelerated carbonation, specimens with 50% replacement of cement and sand achieved compressive strengths of 46.7 MPa, comparable to the non-carbonated reference (47 MPa), indicating full strength recovery despite high substitution levels. Full replacement systems based on alkali activation or carbonation of EAFS achieved moderate compressive strengths (~10 MPa), suitable for non-structural applications, with clear potential for improvement through optimisation of activation and curing conditions. Overall, this work demonstrates that EAFS can be effectively valorised through multiple reaction routes, supporting its role as a versatile and low-carbon resource for sustainable cementitious materials. Full article

Self-compacting concrete (SCC) offers significant advantages in construction due to its superior workability; however, optimizing SCC mixture design remains challenging because of complex nonlinear material interactions and increasing sustainability requirements. This study proposes an integrated, sustainability-oriented computational framework that combines machine learning (ML), SHapley Additive exPlanations (SHAP), and multi-objective optimization to improve SCC mixture design. A large and heterogeneous publicly available global SCC dataset, originally compiled from 156 independent peer-reviewed studies and further enhanced through a structured three-stage data augmentation strategy, was used to develop robust predictive models for key fresh-state properties. An optimized XGBoost model demonstrated strong predictive accuracy and generalization capability, achieving coefficients of determination of $R^2=0.835$ for slump flow and $R^2=0.828$ for $T_{50}$ time, with reliable performance on independent industrial SCC datasets. SHAP-based interpretability analysis identified the water-to-binder ratio and superplasticizer dosage as the dominant factors governing fresh-state behavior, providing physically meaningful insights into mixture performance. A cradle-to-gate life cycle assessment was integrated within a multi-objective genetic algorithm to simultaneously minimize embodied CO${}_2$ emissions and material costs while satisfying workability constraints. The resulting Pareto-optimal mixtures achieved up to 3.9% reduction in embodied CO${}_2$ emissions compared to conventional SCC designs without compromising performance. External validation using independent industrial data confirms the practical reliability and transferability of the proposed framework. Overall, this study presents an interpretable and scalable AI-driven approach for the sustainable optimization of SCC mixture design. Full article

Heteroatom functionalization of graphene is an effective strategy for designing more sustainable lithium-ion battery electrodes, as it can tune both interfacial adhesion and the electronic features of the carbon lattice. In this work, we investigated the interfacial compatibility between three graphene sheets—pristine graphene, graphene doped with one nitrogen atom (Graphene–N), and graphene doped with one sulfur atom (Graphene–S)—and three lignocellulosic binders (carboxymethylcellulose (CMC); coniferyl alcohol (LcnA); and sinapyl alcohol (LsiA)) using density functional theory (DFT). Geometries were optimized using CAM-B3LYP and M06-2X in combination with the LANL2DZ basis set, while ωB97X-D/LANL2DZ was employed for dispersion-consistent single-point refinements. The computed adsorption energies indicate that all binder–surface combinations are thermodynamically favorable within the present finite-model framework (ΔE_int ≈ −22.6 to −31.1 kcal·mol⁻¹), with LSiA consistently showing the strongest stabilization across surfaces. Nitrogen doping produces a modest but systematic strengthening of adsorption relative to pristine graphene for all binders and is accompanied by electronic signatures consistent with localized donor/basic sites while preserving the delocalized π framework. In contrast, sulfur doping yields a more binder-dependent response: it maintains strong stabilization for LSiA but weakens LCnA relative to pristine/N-doped sheets, consistent with an S-induced local distortion/polarizability pattern that can alter optimal π–π registry depending on the adsorption geometry. A combined interpretation of adsorption energies, electronic descriptors (including ΔE_gap as a model-dependent HOMO–LUMO separation), and topological analyses (AIM, ELF, LOL, and MEP) supports that Graphene–N provides the best overall balance between electronic continuity and chemically active interfacial sites, whereas Graphene–S can enhance localized anchoring but introduces more heterogeneous, lone-pair–dominated domains that may partially perturb electronic connectivity. Full article

Concrete 3D printing (3DCP) combines materials science with material processing technologies to enable automated, additive construction. This review summarizes findings from the literature and industrial practice on 3DCP mortar formulation with emphasis on the material processing chain. The workflow is examined from raw material storage through handling, mixing, and deposition. The roles of binders, aggregates, dispersed reinforcement, and chemical admixtures are discussed in relation to rheological behavior, buildability, and early-age mechanical performance. The analysis covers storage, dosing, and mixing strategies with respect to mix consistency and overall process reliability, while mortar pumping and extrusion are addressed alongside nozzle-injected additives and automation. Finally, limitations and scalability challenges are outlined with research directions such as continuous mixing, in-line monitoring, and adaptive mix formulation for on-site applications. Full article

In this paper, the time-dependent properties of the elastic modulus of fly ash concrete under sustained compressive load were studied. An experiment was conducted and showed an increment of elastic modulus for two types of fly ash concrete (20% and 40% fly ash replacement) under sustained load. The mechanisms of this increment were analyzed, and two Representative Volume Elements (RVEs) were established to represent the micro-heterogeneous space of binder and concrete based on continuum mechanics. The shrinking core models of hydration and pozzolanic reaction were adopted to quantify the volume fraction of each phase within the binder RVE. A prediction model was proposed by incorporating the effects of extra hydration and time-dependent aggregate concentration rate under sustained load. Finally, parameter analysis including the influences of initial loading age and the loading level was conducted. Full article

Amid growing environmental concerns, resource depletion, and the pressing challenges of industrial waste management, this study investigates the potential of magnesium slag (MS) as a sustainable alternative binder in the production of one-part geopolymer concretes (OPGCs). The objective is to reduce reliance on conventional cementitious materials while promoting the valorization of industrial by-products in construction practices. For this purpose, ten different mixtures were designed by replacing ground granulated blast furnace slag (GGBS), the conventional aluminosilicate precursor, with MS, an innovative aluminosilicate precursor, at replacement levels of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% by weight, using a solid activator. The fresh and hardened properties of these mixtures were systematically evaluated through slump, setting time, density, ultrasonic pulse velocity (UPV), and strength tests, while microstructural characterization was also conducted using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) to further investigate the geopolymerization process, elemental distribution, and the role of MS in binder formation in OPGC. The results revealed that MS incorporation significantly influenced both workability and mechanical performance, and it was confirmed that MS actively participates in geopolymerization and can be effectively utilized up to a certain threshold. Replacement levels up to 30% were found to maintain acceptable mechanical performance, providing evidence that MS is a promising precursor for developing sustainable OPGC. Full article

The aim of this study is to investigate the potential applications of pine cones as plant-based waste material in the construction industry. In order to achieve this target, the pine cone particles (PCP) are mixed with cement to create new lightweight concretes. Furthermore, pine tree resin (PTR), acting as a natural bio-polymer binder, is incorporated into selected samples to ascertain its potential as a binder. The pine cones are cut into particles of 2–4 cm, 0–2 cm, and ground into a powder. A series of critical tests is conducted on the novel produced samples, including thermal conductivity, specific heat, density, compressive strength, water absorption rate, and drying rate. The experiments show that thermal conductivity, specific heat capacity, and thermal expansion coefficient decrease as the weight ratio and size of PCP increase. The presence of PTR increases porosity, further decreasing thermal conductivity, specific heat, and thermal expansion coefficients for the majority of samples. The compressive strength values decrease with the presence of PTR and PCP. Regarding durability, the water absorption ratios remain below the critical 30% threshold, making the material suitable for internal applications or external facades protected by coating/plaster or as external coverings. Full article

The reliability of the mechanical property values adopted for current pavement structural design remains low. Therefore, this study investigated the nonlinear characteristics for the tensile and compressive properties of cement-stabilized macadam (CSM) and an asphalt mixture (AM) under different gradation types and loading rates. And a multi-factor value model was developed for both. The results show that the tensile and compressive stress–strain behavior of both CSM and AM exhibited bilinear characteristics consistent with the bi-modulus theory (elasticity with different moduli in tension and compression). The strength, elastic modulus, and Poisson’s ratio followed a power function relationship with increasing loading rates, stabilizing at values beyond 0.1 MPa/s. The skeleton-dense gradation demonstrates the most favorable mechanical performance. For semi-open-graded AM with a void ratio of 8~16%, the mechanical parameters exhibit relatively high rates of change. Among the influencing factors, gradation type had the most significant impact on the mechanical parameters, especially on the elastic modulus. In general, tensile mechanical parameters were more sensitive to changes than compressive ones. R_c/R_t was most strongly affected by gradation type. Accordingly, a quantitative value model was established to describe the variation in tensile and compressive mechanical parameters of typical asphalt pavement materials, which vary with air void ratio, loading rate, binder content, and temperature. The findings provide a reference for the prediction of pavement structure design parameters considering the difference in compression and tension. Full article

This study evaluates the mechanical properties and durability of novel self-shrinking chitosan fibers incorporated into a High-Performance Concrete (HPC) matrix. The cementitious system comprised a 75–25% blend of Portland Limestone Cement (PLC) and Ground Glass Pozzolan (GGP). Two variants of chitosan—food-grade and high-grade—were processed into fibers and integrated at dosages of 0.36%, 0.73%, and 1.45% by weight of binder, alongside a 0% control group. The experimental program assessed eight distinct mixtures through extended freeze–thaw testing (up to 602 cycles), electrical resistance monitoring, and compressive strength evaluation at 56 and 90 days. Results indicated that food-grade chitosan fibers caused a substantial reduction in compressive strength, ranging from 40% to 70% depending on the dosage. Despite this mechanical loss, these mixtures showed localized improvements in freeze–thaw resistance and electrical resistivity. Conversely, the high-grade chitosan fibers exhibited severe performance degradation under freeze–thaw cycling; all reinforced groups fell below 80% relative dynamic modulus, with two mixtures dropping below the 60% failure threshold. In comparison, the control mixture retained 98% of its dynamic modulus after 602 cycles. Ultimately, the findings suggest that, in their current formulation, self-shrinking chitosan fibers do not provide consistent or reliable enhancements to the structural integrity or durability of high-performance concrete. Full article

Background/Objectives: The progression and dissemination of CRC are heavily influenced by a subpopulation of tumor cells known as CSCs. This study aimed to identify novel protein membrane antigens expressed by colorectal CSCs and the consequent development of targeted therapies based on monoclonal antibodies directed against the identified antigens. Methods: Integrated bioinformatics analyses were conducted using proprietary CSC gene expression profiles and public colon gene expression databases, leading to the identification of five plasma membrane proteins enriched in CSCs. Genetic immunization in rats was employed to generate monoclonal antibodies (mAbs) targeting these antigens. FGFR4 was prioritized due to its overexpression in colorectal tumors. Its function was characterized in vitro and in vivo through assays evaluating proliferation, colony formation, migration, and tumorigenicity. The anti-FGFR4 antibody 3B6 was selected based on its affinity and ability to inhibit FGFR4 signaling in CSCs. Its therapeutic potential was further assessed in xenograft models, and alterations in downstream signaling were analyzed via Western blot. Results: FGFR4 emerged as a key regulator of CRC CSC proliferation, migration, and tumorigenic capacity. The 3B6 antibody, a high-affinity FGFR4 binder, demonstrated robust in vitro inhibition of CSC features and significant antitumor effects in patient-derived xenograft models. Western blot analysis confirmed the modulation of FGFR4-driven signaling pathways, particularly those involved in epithelial–mesenchymal transition (EMT). Conclusions: This study successfully identified several CSC-selective membrane antigens that can become therapeutic targets in CRC. Among them, we focused on FGFR4 as a promising target and developed the anti-FGFR4 3B6 monoclonal antibody which offers potential for both diagnostic and therapeutic applications. Full article

Recent studies have highlighted the potential for production of an alternative sodium silicate in powder obtained by mixing NaOH with rice husk ash, followed by a dissolution and drying process. This alternative sodium silicate, when mixed with metakaolin and dried under special conditions, results in an eco-friendly one-part alkali-activated binder (OPAAB). However, the durability performance of OPAAB incorporating RHA-derived sodium silicate remains largely unexplored. This study focuses on an experimental investigation of OPAAB mortar durability, analyzing permeability, high-temperature exposure, wet-and-dry cycles, and resistance to aggressive environments (sulfate and acid attack). A two-part mix mortar made with the same precursors was used as a reference. It was found that the OPAAB mortars were not affected by the wet-and-dry cycles nor the sulfate attack. Exposure to high temperature (900 °C for 1 h) did not cause specimen failure, which had a residual compressive strength higher than 5 MPa. Finally, exposure to sulfuric acid for 56 days decreased the mechanical strength of the mortars, but all the specimens maintained a residual compressive strength higher than 4 MPa. The durability performance of the mortars produced with OPAAB incorporating RHA-derived sodium silicate was similar to the two-part mix mortars (reference), demonstrating technical feasibility and advancing the understanding of durability aspects for application in civil construction. Full article