Materials and Structures最新文献

{"title":"Evaluation of fresh-state application performance of a coating mortar based on aerial lime and tuffeau powder from stone sawing waste","authors":"Malek Balawi,&nbsp;Kévin Beck,&nbsp;Naima Belayachi,&nbsp;Xavier Brunetaud","doi":"10.1617/s11527-025-02611-2","DOIUrl":"10.1617/s11527-025-02611-2","url":null,"abstract":"<div><p>To reduce the overexploitation of granular resources, minimize the environmental impact of fine mortars, and limit the heritage impact during the rehabilitation of old tuffeau stone buildings in the Loire Valley, France, a new coating mortar has been developed. Composed of aerial lime and tuffeau powder from sawn stone blocks, this mortar promotes the reuse of mineral waste. Due to its use as a finish coat on external insulation vertically, it requires specific characteristics in its fresh state to facilitate its application and accurately replicate the original stone's aesthetic appearance in the restored buildings. Different additives were used to optimize the material's performance: superplasticizer (SP), shrinkage-reducing agent (SRA), air-entraining agent (AEA), and rheology modifier (RM). This paper examines the fresh state behavior of the developed material by employing a methodology that combines flow table and fall cone tests. It provides an objective approach capable of assessing consistency and determining application requirements that align with the empirical properties recommended by professionals in the field. Additionally, the entrained air content and bulk density were determined. The flow table failed to identify the impact of adding AEA on application performance. However, the fall cone test revealed its influence, highlighting AEA’s role in facilitating mortar application. The SP predominantly reduced the water requirement needed to achieve specific flowability. Integrating RM with AEA enhanced the mortar’s ability to retain entrained air.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation on the healing effects of microwave heating in eco-friendly pavement using e-waste","authors":"Kai Liu,&nbsp;Yixiang Zhang,&nbsp;Fang Wang,&nbsp;Yi Da,&nbsp;Hongbo Zhang,&nbsp;Huanping Pang","doi":"10.1617/s11527-025-02603-2","DOIUrl":"10.1617/s11527-025-02603-2","url":null,"abstract":"<div><p>Incorporating e-waste into asphalt pavements can enhance their ability to absorb microwaves, allowing the asphalt to quickly reach its softening point under microwave exposure, flow, and fill cracks, achieving self-healing of the pavement. Depending on different heating principles, the added e-waste can be divided into two categories: microwave absorbing materials and metal shielding material. However, regardless of which material is added alone, during the microwave heating process, microwave energy will decrease along the propagation direction, leading to temperature differences in the pavement and causing uneven healing among different layers. To address this issue, this paper proposes a self-healing asphalt pavement (SHAP), where microwave absorbing materials are gradiently incorporated into the upper and middle layers of the pavement with more microwave energy, while metal reflective materials are added to the lower layer where electromagnetic energy has significantly decayed, thereby increasing the microwave absorption capacity of the pavement layer by layer. This achieves a similar warming trend across all layers after microwave heating. Based on microwave heating experiments, the effects of different added e-waste materials on the microwave heating of the pavement were studied, determining the optimal type of e-waste for each layer of the SHAP. An overall healing index (HI_average) was proposed, to maximize the HI_average, a predictive model was established using response surface methodology to determine the optimal dosage of e-waste for each layer of SHAP. Finally, a life cycle assessment demonstrated that SHAP exhibits significant economic and environmental advantages compared to conventional pavements.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A fully coupled viscoelastic continuum damage model for asphalt concrete","authors":"Valappol Navjot,&nbsp;S. P. Atul Narayan","doi":"10.1617/s11527-025-02597-x","DOIUrl":"10.1617/s11527-025-02597-x","url":null,"abstract":"<div><p>Capturing the fatigue-induced evolution of viscoelastic properties of the material is crucial for predicting the fatigue life of asphalt concrete pavements. Current prediction models are often regression-based and lack accuracy, necessitating the adoption of mechanistic models like the Viscoelastic-Continuum Damage (VECD) models. The VECD models often rely on Schapery’s work potential theory and elastic-viscoelastic correspondence principles, using pseudo-strain to separate viscoelasticity from damage mechanics. However, this decoupling imposes constraints on how viscoelastic properties can evolve. This study presents a new VECD model that fully couples the viscoelasticity of the material with its damage characteristics. It was developed within a Helmholtz-potential-based thermodynamic framework, ensuring consistency with the laws of thermodynamics. The model could describe the evolution of both the apparent storage modulus and loss modulus during fatigue tests over a wide range of strain levels. It captures the three-stage fatigue behavior of asphalt concrete, allows for unconstrained variations in the apparent phase angle, and provides a clear point of failure. Moreover, it can capture the variation of fatigue life with the applied strain level in a manner similar to the Asphalt Institute fatigue life model.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving the carbonation resistance of alkali-activated slag mortars by MgO with different reactivity","authors":"Mingtao Zhang,&nbsp;Hua Zhang,&nbsp;Han Tang,&nbsp;Yi Sun,&nbsp;Changming Bu,&nbsp;Jingwen Zhang,&nbsp;Zeping Wang,&nbsp;Xin Li","doi":"10.1617/s11527-025-02596-y","DOIUrl":"10.1617/s11527-025-02596-y","url":null,"abstract":"<div><p>Alkali-activated slag (AAS) is a low-carbon construction material and exhibits high mechanical strength and good fire resistance. However, compared to ordinary Portland cement, AAS has a greater problem in terms of resistance to carbonation. In this study, three reactive MgO and Mg(OH)₂ were used to enhance the carbonation resistance of AAS mortars. It was found that both reactive MgO and Mg(OH)₂ were able to improve the carbonation resistance of the AAS mortar, and the reactive MgO was more effective than Mg(OH)₂. Increasing the reactivity and dosage of MgO can significantly enhance the carbonation resistance of AAS mortar, resulting in a 70<i>.</i>5% reduction in carbonation depth. The compressive strength, phase composition, and microstructure before and after carbonation were tested, which showed that the highly reactive MgO had a greater accelerating effect on the hydration of AAS. It can not only significantly improve the compressive strength of AAS mortar but also limit the diffusion of CO₂ into the mortar. Meanwhile, the introduction of higher reactive MgO produced more hydrotalcite with a laminar structure, which could absorb a large amount of CO₃²⁻. In addition, the incompletely hydrated MgO could react directly with CO₂ during the carbonation process to achieve the purpose of carbon sequestration.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and application of environmentally friendly liquid alkali-free and fluorine-free accelerator for shotcrete","authors":"Peng Hu,&nbsp;Hongyu Ji,&nbsp;Kun Wang,&nbsp;Feng Zhao,&nbsp;Baicheng Liu,&nbsp;Rongxiao Sun,&nbsp;Yulong Zhao","doi":"10.1617/s11527-025-02601-4","DOIUrl":"10.1617/s11527-025-02601-4","url":null,"abstract":"<div><p>A liquid accelerator is a key component in shotcrete; however, it often faces challenges such as high alkali content and insufficient long-term concrete strength. This study utilizes polyaluminum sulfate as the primary raw material to develop an environmentally friendly, alkali-free, and fluorine-free accelerator (FAF). Through orthogonal experiments and cement compatibility tests, the effects of FAF on setting time, 1 day compressive strength, and 28 days compressive strength ratio of cement paste were analyzed, leading to the determination of the optimal FAF mixing ratio. The coagulation-promoting mechanism of FAF was further examined using X-ray diffraction (XRD) and scanning electron microscopy (SEM) results. Additionally, concrete slab tests were conducted to assess the impact of different FAF dosages on concrete rebound rates and mechanical properties, with the optimal dosage range found to be 4–8%. Field trials indicated that, at a 6% FAF dosage, shotcrete rebound rates on tunnel arch walls and roofs were 10.3% and 13.5%, respectively. The composition of the FAF does not contain alkali metal salts, which reduces the risk of alkali-aggregate reactions in concrete and minimizes the potential health risks to construction personnel, aligning with the global trend towards sustainable construction practices.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing the steel-concrete interface microstructure using FIB-SEM nanotomography","authors":"Thilo Schmid,&nbsp;Nicolas Ruffray,&nbsp;Michele Griffa,&nbsp;Zhidong Zhang,&nbsp;O. Burkan Isgor,&nbsp;Ueli M. Angst","doi":"10.1617/s11527-025-02602-3","DOIUrl":"10.1617/s11527-025-02602-3","url":null,"abstract":"<div><p>While it is widely accepted that the steel-concrete interface (SCI) plays an important role in governing the long-term durability of reinforced concrete structures, the understanding about the primary features of the SCI that influence corrosion degradation mechanisms has remained elusive. This lack of knowledge can be attributed to, firstly, the complex heterogeneous nature of the SCI, and secondly, the absence of established experimental techniques suitable for studying the relevant SCI features. Here, we use focused ion beam—scanning electron microscopy (FIB-SEM) nanotomography to obtain high-resolution 3D tomograms of the SCI. Five tomograms, spanning volumes ranging from 8000 to <span>({200,000},{upmu hbox {m}^{3}})</span>, of both non-corroded and corroded SCIs were acquired. The achieved voxel size falls within the range of 30–50 nm, which captures capillary pores highly relevant for moisture and ion transport. Potential pitfalls when applying the FIB-SEM technique to the SCI are highlighted, including aspects related to the electron detectors. We present an image processing pipeline that reduces artifacts and generates tomograms segmented into solid matrix and pore space. Furthermore, to characterize the SCI pore structure, diffusion tortuosity and porosity profiles. The analysis showed that there is a pronounced anisotropy in the pore structure. This work demonstrates that the FIB-SEM technique can be applied to acquire high resolution tomograms of the SCI pore structure, which can be digitally analyzed to inform transport models of the SCI.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02602-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D Printable Ca(OH)2-based geopolymer concrete with steel fiber reinforcement","authors":"Youssef Mortada,&nbsp;Ahmad Hammoud,&nbsp;Laith Masoud,&nbsp;Mateusz Wyrzykowski,&nbsp;Davide Sirtoli,&nbsp;Pietro Lura,&nbsp;Bilal Mansoor,&nbsp;Eyad Masad","doi":"10.1617/s11527-025-02600-5","DOIUrl":"10.1617/s11527-025-02600-5","url":null,"abstract":"<div><p>This study investigates the impact of varying steel fiber (SF) content (0%, 0.8%, 1.0%, and 1.2% by volume) on the mechanical and durability properties of 3D-printed Ca(OH)₂-activated geopolymer concrete (GPC). The addition of 1.2% SF improved flexural strength by 69% at 7 days and 16% at 28 days, while tensile strength more than doubled to 3.75 MPa at 28 days. Although compressive strength remained unaffected at 43 MPa, SF enhanced interlayer bond strength by 20%, which is crucial for layer cohesion in 3D-printed structures. Additionally, the elastic modulus increased by 7%, contributing to improved stiffness. Durability assessments, including autogenous shrinkage and self-induced stress, indicated a slight reduction in shrinkage of SF-reinforced samples, with no significant effect on self-induced stress. Microstructural analysis using scanning electron microscopy (SEM) and X-ray micro-computed tomography (µCT) demonstrated the crack-bridging behavior of steel fibers, enhancing ductility and fracture resistance. There was a slight increase in porosity (5.34%) of SF-reinforced samples without negatively affecting their mechanical properties. Notably, SF improved early-age toughness and controlled crack propagation across printed layers, addressing a critical challenge in 3D-printed concrete. The novelty of this work lies in successfully reinforcing 3D-printed Ca(OH)₂-activated GPC with recycled steel fibers, enhancing mechanical properties, interlayer bonding, and durability without compromising printability. This study offers a sustainable reinforcement strategy for 3D printing in construction.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02600-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-scale study of pre-damage, water boundary conditions and frost interaction in concrete","authors":"Lang-Zi Chang,&nbsp;Katja Frid,&nbsp;Roland Kruse,&nbsp;Ralf Jänicke,&nbsp;Karin Lundgren","doi":"10.1617/s11527-025-02599-9","DOIUrl":"10.1617/s11527-025-02599-9","url":null,"abstract":"<div><p>This study investigated the interactive effects of pre-damage, water boundary conditions, and internal frost damage on concrete at dual-scale. The pre-damage included pre-cracking, which has not been studied experimentally before, and pre-compressive damage. Concrete specimens underwent pre-damage and had varied water boundary conditions during Freeze-Thaw Cycles (FTC). At the macro-scale, wedge-splitting tests combined with Digital Image Correlation (DIC) were conducted to assess post-FTC strength and fracture behaviour. At the meso-scale, X-ray CT scanning was employed to identify internal crack patterns. Results reveal that at the macro-scale, significant interaction between pre-damage and frost damage reduced splitting tensile strength compared to the internal frost damage alone. Besides, increased water exposure during FTCs reduced both splitting tensile strength and compressive strength, with a less pronounced reduction in splitting tensile strength. It also led to a diffuse crack pattern and increased tensile ductility. At the meso-scale, specimens subjected to the interactive effects of pre-damage and internal frost damage exhibited cracks along aggregate-cement interfaces and within the cement paste. Reference specimens displayed no internal cracks, while specimens exposed to only FTCs showed only cracks along aggregate-cement interfaces. Full submersion of specimens during FTCs induced more internal cracks than solely water on top. These findings on the interactions between pre-damage, water boundary conditions, and internal frost damage offer insight into the causes of frost damage, vital for the design and assessment of concrete structures in frost-prone environments. Furthermore, the results of these dual-scale tests can be used as a test case for the development of upscaling numerical models describing heat transfer and frost degradation in concrete.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02599-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143455676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical properties of sustainable freshwater marine sand mortar","authors":"Amelia Pei Sze Chai,&nbsp;Mei Yun Chin,&nbsp;King Kuok Kuok,&nbsp;Md Rezaur Rahman","doi":"10.1617/s11527-025-02571-7","DOIUrl":"10.1617/s11527-025-02571-7","url":null,"abstract":"<div><p>Marine sand has gained significant interest among researchers as a potential solution to the shortage of river sand for construction purposes. However, using marine sand as a fine aggregate in mortar has yielded contradictory results. To investigate the underlying reasons for this phenomenon, an experimental study was conducted to study the influence of marine sand with different characteristics on the mechanical performance of mortar. The shape and size of marine sand significantly impact its loose bulk density, voids and water absorption. The properties of marine sand mortar include workability, hardened density, flexural strength, and compressive strength. Beach marine sand, with its fine and uniform particles, requires higher water content, resulting in lower workability. This reduction in workability leads to decreased mechanical strength due to the increased voids within the mortar. However, marine sand’s sub-angular to angular shape contributes to mechanical strength by bonding with the cement paste and through the interlocking action between sand particles. Despite this, it has been found that the presence of voids within the mortar is the dominant factor contributing to its low mechanical strength. The flexural strength of marine sand mortar was reduced by 16.9%–49.3% compared to river sand mortar, while the compressive strength decreased by 20.9%–64.9%. One important finding is that marine sand that contains impurities such as coral skeletons and seashell fragments significantly reduces the mechanical performance of marine sand mortar. Based on this observation, it is evident that not all marine sand is suitable for use as fine aggregate in mortar.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02571-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification and quantification of minor iron-sulfide concentrations in concrete aggregate using automated mineralogy","authors":"Nikolas Oberhardt,&nbsp;Stefanie Lode,&nbsp;Jan Lindgård,&nbsp;Kurt Aasly","doi":"10.1617/s11527-025-02591-3","DOIUrl":"10.1617/s11527-025-02591-3","url":null,"abstract":"<div><p>Iron sulfide concentrations and mineral associations triggering the internal deterioration of concrete structures are still enigmatic. Incidences of internal sulfate attacks induced by iron sulfide-containing concrete aggregates appear worldwide. Severe cases are reported from Canada, the United States of America, and Ireland. Moreover, conservative limits for the total sulfur content of aggregates increased the need to dispose of otherwise high-quality resources for concrete production. The maximum threshold values for total elemental sulfur in the European standard EN-12620 for concrete aggregates are <span>(le)</span> 1 wt.<span>(%)</span>, and as little as <span>(le)</span>0.1 wt.<span>(%)</span> if the non-stoichiometric iron-sulfide pyrrhotite (Fe_(1-x)S) is present in the rock. This study investigates the potential of scanning electron microscopy-based automated mineralogy for mineral classification and the quantitative quality assessment for concrete aggregate material. Identifying the stoichiometrically closely related disulfide pyrite and monosulfide pyrrhotite is emphasized. The iron/sulfur ratio and greyscale variations in the electron backscatter images between pyrite and pyrrhotite were tested as additional differentiation criteria when acquiring mineral mapping and point-of-interest analysis. The added greyscale criterion yielded a better distinction between the two chemically similar phases. A good correlation was achieved when comparing results from energy-dispersive X-ray spectroscopy in automated mineralogy with wavelength-dispersive spectroscopy point analyses on the electron microprobe. Semi-quantification of the chemical data from automated mineralogy was computed for the total sulfur content in the petrographic samples. The total sulfur content of bulk samples, investigated by high-temperature combustion and inductively coupled plasma atomic emission spectroscopy, was consistent with the semi-quantitative results of automated mineralogy.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 2","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02591-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}