Materials and Structures最新文献

{"title":"Decarbonized 3D printed concrete incorporating lithium slag and PVA fiber: buildability, mechanical, and microstructural insights","authors":"SM Arifur Rahman,&nbsp;Sanjida Khair,&nbsp;Faiz Uddin Ahmed Shaikh,&nbsp;Prabir Kumar Sarker","doi":"10.1617/s11527-025-02768-w","DOIUrl":"10.1617/s11527-025-02768-w","url":null,"abstract":"<div><p>The 3D concrete printing technology is ubiquitously enhancing modern construction, while its’ production generates high carbon footprint due to high cement content in the mix. The use of low–carbon pozzolans in 3D concrete printing reduces cement usage, however low–volume incorporation of these pozzolans insignificantly offset the carbon footprint. This study pioneers the use of 40% lithium slag (LS) as a cement replacement in the production of decarbonized 3D printed concrete and assesses the changes in rheology, buildability, mechanical, and microstructural properties with/without 1% polyvinyl alcohol (PVA) fibre. The 40% LS mix enhanced 13% higher plastic viscosity recovery compared to the control, and the corresponding buildability height was increased by 34% in the same comparison. At 28 days, the control and 40% LS specimens gained 34.2 MPa and 32.1 MPa of compressive strength. The flexural and bond strengths of 40% LS mix were 3.90 MPa and 2.23 MPa at 28 days. PVA (1 vol.%) fibres incorporated 40% LS mix enhanced the printing quality by reducing the filament breaking, which gained 4.60 MPa and 2.52 MPa of flexural and bond strengths at 28 days. Microstructural analysis using BSE-EDS indicated the formation of amorphous and amorphous intermediate hydration products in contributing mechanical strength development of LS-based 3D-printed concretes. PVA fibre incorporated 40% LS mix reduces 31% embodied carbon compared to the control and establishes its potential to decarbonize and enhance the performance of 3D-printed concretes.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02768-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144926960","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":"Preparation of new coal gangue-based cementitious material via hydrothermal synthesis–low temperature calcination method","authors":"Tingye Qi,&nbsp;Lubin Li,&nbsp;Junjie He,&nbsp;Guorui Feng,&nbsp;Linfei Wang,&nbsp;Hongtao Xu,&nbsp;Tian Qiu,&nbsp;Siyuan Cheng,&nbsp;Xinkai Qi,&nbsp;Kexin Xu","doi":"10.1617/s11527-025-02769-9","DOIUrl":"10.1617/s11527-025-02769-9","url":null,"abstract":"<div><p>Traditional cement-based materials’ economic and environmental concerns urge low-carbon alternatives. This study activates coal gangue via hydrothermal synthesis − low temperature calcination to explore optimal activation conditions for cement substitution. A Box-Behnken response surface experiment was designed with 28d compressive strength as the response index to study the effects of hydrothermal temperature, Ca/Si ratio, NaOH concentration, and calcination temperature on coal gangue-based cementitious materials. Single-factor optimization was conducted based on significant factors identified via response surface analysis. Phase evolution and hydration mechanisms were analyzed using XRD, SEM, TG-DSC, etc. Results indicated that optimal conditions were 90 °C, Ca/Si = 2.0, NaOH = 1.5%, and 800 °C, with the Ca/Si ratio and calcination temperature exerting the most significant impact, achieving a 28d compressive strength of 20.1 MPa. At Ca/Si = 2.0, the highest content of C₁₂A₇ was found in the clinker. The formation of β-C₂S and α’_H-C₂S at 800 °C facilitated the densification of C–S–H with ettringite. Hydrothermal pre-treatment lowered the C₂S synthesis temperature by 200 °C and enhanced the 28d compressive strength to 191% of that obtained using the one-step calcination method. The results provide theoretical support for the utilization of coal gangue as a cementitious material, promoting its sustainable resource utilization.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918303","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":"On the effect of thermal strains in slender prestressed concrete beams","authors":"Gonzalo Ruano,&nbsp;Virginia Quintana,&nbsp;Armando La Scala,&nbsp;Dora Foti","doi":"10.1617/s11527-025-02739-1","DOIUrl":"10.1617/s11527-025-02739-1","url":null,"abstract":"<div><p>In construction sector, prestressed concrete beams are commonly used, even in ordinary buildings; as a consequence, their exposure to various risk factors, including fires or high thermal gradients, is quite high. Extensive research has focused on concrete structures under extreme loading conditions, but slender prestressed members have proven unique and challenging in the understanding of mechanical response and their numerical modelling, particularly regarding the interaction between thermal gradients and prestressing forces. In fact, unlike ordinary concrete beams and columns, these structures are particularly sensitive to temperature changes and temperature gradients. In addition, their thermo-mechanical response is further complex due to the interaction of thermal loads with pre-existing prestressing stresses, which vary over time as a function of temperature field. This work explores this dual behavior by means of numerical simulations including temperature-dependent material properties, focusing on the thermal expansion coefficient (<i>α</i>) and thermal transient creep. Using a staggered scheme finite element modelling, the analysis applies a coupled thermo-mechanical approach. The model has been validated on a series of experimental tests carried out at Polytechnic of Bari. The comparison showed the model capability to capture the influence of temperature-dependent strains on these slender structures. The results highlight how even minor variations in thermal properties can affect the mechanical response, providing insights essential for the safe design of prestressed concrete elements under thermal loads.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02739-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144920496","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":"The influence of LC3 on the rheology of cementitious matrices: a systematic review of key rheological impact characteristics","authors":"Ariel Miranda de Souza,&nbsp;José Maria Franco de Carvalho,&nbsp;Gabriela Moreira Silva,&nbsp;Leonardo Gonçalves Pedroti,&nbsp;Guilherme Jorge Brigolini Silva,&nbsp;Ricardo André Fiorotti Peixoto","doi":"10.1617/s11527-025-02753-3","DOIUrl":"10.1617/s11527-025-02753-3","url":null,"abstract":"<div><p>The increasing demand for eco-efficient construction drives the search for alternatives that reduce clinker use in cement. LC³ cement, which uses calcined clay and limestone to partially replace clinker, shows excellent mechanical performance but presents rheological challenges such as high yield stress, increased viscosity, and greater water demand. Understanding the factors affecting LC³ rheology is key for developing technologies to adapt it to market needs. This study reviews recent research to identify key factors influencing LC³ rheology, including the morphology of calcined clay particles, flocculation tendency, zeta potential, particle packing, LC³ reactivity, and admixture sorption in expansive clays. The findings suggest that optimizing LC³ formulations can enhance its rheological performance. Additionally, using industrial waste as supplementary materials shows potential for modifying LC³’s rheology, and LC³ has promising applications in 3D-printed mortars, where its rheological properties can be adjusted for extrusion and buildability.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914614","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":"Tensile behaviour of four LVL-truss end connections for timber spatial structures","authors":"Andrea Fabbri,&nbsp;Fabio Minghini,&nbsp;Nerio Tullini","doi":"10.1617/s11527-025-02763-1","DOIUrl":"10.1617/s11527-025-02763-1","url":null,"abstract":"<div><p>This study analyzes four types of steel-to-timber connections for potential use in spatial truss structures with high-performance, small-section Laminated Veneer Lumber (LVL) elements. The experiments were comprised of 42 monotonic pull-pull tests, including 30 tests on dowel-type connections and 12 tests on screwed connections. Dowel-type connections were subdivided into dowel-nut connections and bolted connections featuring either one inner or two outer steel plates. None of the dowel-type connections met code requirements on minimum lateral-edge distance. For some configuration, also loaded-end distance was non-conforming. Screwed connections used a threaded insert parallel to the longitudinal element axis, accommodating a metric threaded rod. Even in this case, the connection was non-conforming due to violation of code requirements on edge distance and inclination angle with respect to veneer planes. Bolted connections showed high load-carrying capacities, but at the cost of a significant steel usage. The screwed connection, while reducing steel usage, exhibited high stiffness but relatively small load-carrying capacity. This last one, however, was shown to be improved by the application of transverse confinement. The dowel-nut connection proved to be particularly effective, combining good mechanical performance with a low aesthetic impact. These results provide valuable insights into the design of safe and efficient connections for LVL spatial structures, contributing to the growth of knowledge on sustainable engineering applications.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02763-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914619","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":"Physical properties and microstructure of sustainable lightweight aggregates prepared from lead–zinc tailings and fly ash under different sintering regimes","authors":"Jianxiang Huang,&nbsp;Shouwei Jian,&nbsp;Hongbo Tan,&nbsp;Xiangguo Li,&nbsp;Jian Huang,&nbsp;Yang Lv,&nbsp;Baodong Li,&nbsp;Xin Gao,&nbsp;Bo Peng,&nbsp;Xiwen Guan","doi":"10.1617/s11527-025-02767-x","DOIUrl":"10.1617/s11527-025-02767-x","url":null,"abstract":"<div><p>Lead–zinc tailings (LZT), a low-value mining waste, pose significant environmental and health risks due to their massive accumulation. This study addresses the need for harmless and efficient treatment of LZT by successfully producing lightweight aggregates (LWA) from 100% solid waste (low-cost LZT and poor-quality fly ash) without secondary pollution. The relationship between sintering conditions and LWA properties was investigated, revealing that sintering temperature significantly influences LWA performance more than other parameters. Specifically, it is the core factor controlling particle density, while both sintering temperature and time strongly affect compressive strength. Microstructure analysis showed that over 50% of the total pore area consisted of pores with diameters of 100–1000 μm. Insufficient preheating or excessively high sintering temperatures led to the formation of pores larger than 1 mm, while extending sintering time from 20 to 40 min increased the proportion of 100–1000 μm pores. XRD and FTIR analyses indicated that strength development was attributed to the formation of aluminosilicate skeletons and feldspar phases during sintering. Life cycle assessment (LCA) revealed that sintering at 1100–1150 °C for 30–35 min optimally balances LWA strength, energy consumption, environmental impact, and cost. This study offers an innovative and eco-friendly strategy for low-energy utilization of multi-source solid waste.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914615","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 of specialized plastering mortar for foam concrete using low silica iron tailings","authors":"Lutao Xue,&nbsp;Yubiao Li,&nbsp;Rui Li,&nbsp;Wenqiang Yu","doi":"10.1617/s11527-025-02750-6","DOIUrl":"10.1617/s11527-025-02750-6","url":null,"abstract":"<div><p>The mismatch in physical properties between traditional mortar and the porous substrate of foam concrete (FC) leads to poor adhesion and cracking, limiting the wider application of FC. In order to address this issue and alleviate the storage pressure of low silica iron tailings (LSIT), this study developed an advanced plastering mortar system for foam concrete blocks through systematic optimization of LSIT. A comprehensive evaluation was conducted on six critical parameters, including the water-cement ratio, the aggregate ratio of LSIT to sand, the content of cement, hydroxypropyl methyl cellulose (HPMC), re-dispersible latex powder (RDP), and polypropylene fiber (PPF), establishing their quantitative impacts on mortar performance. The optimal performance was achieved with a water-cement ratio of 0.84, aggregate ratio of 11:3, cement content of 30%, HPMC content of 0.4%, RDP content of 1.5%, and PPF content of 0.15%, yielding a mortar density of 1447.9 kg/m³, 28 d compressive strength of 8.21 MPa, and 104 mm consistency, parameters fully compliant with the M8 grade specifications in JC/T 890-2017. Advanced microstructural characterization (XRD, SEM, and hydration heat analysis) demonstrated that LSIT particles refined the granulometric distribution through microaggregate effects. In addition, C₃S dissociation was retarded by HPMC through Ca²⁺ chelation, extending the induction period of hydration. Moreover, the RDP facilitated interfacial cross-linking via transesterification, forming the core–shell structures of C–S–H and polymer, compared with the control sample, the portlandite content was slightly reduced. Furthermore, the PPF reinforcement is achieved through crack-deflection and bridging mechanisms. The modification system of multi-component materials therefore exhibits a three-fold synergistic action, including the gradation optimization of particles, the regulation of hydration kinetics, and the toughening of the interfacial. These findings establish a viable pathway for high-value utilization of iron tailings in construction materials and simultaneously elucidate the physicochemical mechanisms underlying the interactions of composite modifiers in cementitious systems. Furthermore, the modified additive system serves as a viable template for valorizing diverse solid wastes.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914547","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":"Experimental assessment of reinforced concrete squat walls with high-strength lightweight concrete","authors":"Karla Patiño-Mora,&nbsp;Hernán Santa María,&nbsp;Rosita Jünemann","doi":"10.1617/s11527-025-02756-0","DOIUrl":"10.1617/s11527-025-02756-0","url":null,"abstract":"<div><p>This study experimentally evaluates the seismic behavior of reinforced concrete squat walls constructed with high-strength lightweight concrete using expanded clay as lightweight aggregate. Four specimens with identical geometry and reinforcement were tested under monotonic and cyclic loading to assess shear capacity, stiffness degradation, and energy dissipation. Results indicate that the lightweight concrete walls tested exhibited comparable shear strength and cyclic performance to normal-weight concrete walls, despite a 40% lower initial stiffness, but also demonstrated superior behavior compared to other lightweight concrete walls documented in literature with similar characteristics. The experimental shear strength exceeded the nominal capacity predicted by the ACI 318 code, suggesting that the code’s lightweight reduction factor may be overly conservative for high-strength lightweight concrete mixtures. Notably, the results demonstrate the influence of aggregate type on concrete mix in shear response. The study contributes to understanding the nonlinear performance of lightweight concrete walls under lateral loads, providing experimental data that could refine design methodologies for such structures in seismic-prone regions.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144905211","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":"Effect of fatigue loading parameters on the flexural fatigue of steel fiber reinforced concrete beams","authors":"Iranildo Barbosa da Silva Junior,&nbsp;Vitor Moreira de Alencar Monteiro,&nbsp;Cássio Marques Rodrigues Gaspar,&nbsp;Flávio de Andrade Silva","doi":"10.1617/s11527-025-02771-1","DOIUrl":"10.1617/s11527-025-02771-1","url":null,"abstract":"<div><p>This work presents the results of an experimental investigation on the fatigue behavior of Structural Fiber Reinforced Concrete (R/SFRC) beams. By incorporating steel fiber reinforcement, R/SFRC beams exhibit enhanced durability, crack control, ductility, toughness, and strength compared to beams with conventional steel rebars (RC) without fibers. Moreover, the use of steel fibers in a concrete matrix may allow a reduction of steel reinforcement in structural elements. Fatigue tests were performed at a continuous stress level corresponding to 80% of the steel yield strain, with loading frequencies of 6 Hz and 0.35 Hz and stress ratios of 0.3 and 0.1. The results indicate that incorporating steel fibers promotes a more uniform distribution of tensile stresses, thereby enhancing the fatigue life of the beams. Furthermore, lower frequencies intensify mechanical degradation due to increased energy release per cycle. At elevated stress amplitudes, the reduction in stiffness becomes more pronounced, which further compromises fatigue performance.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144909722","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":"Article of RILEM TC 278-CHA: evaluation of self-healing properties of asphalt binders—outcomes and challenges","authors":"O. Baglieri,&nbsp;R. Aurilio,&nbsp;F. Miglietta,&nbsp;L. Tsantilis,&nbsp;H. Baaj","doi":"10.1617/s11527-025-02762-2","DOIUrl":"10.1617/s11527-025-02762-2","url":null,"abstract":"<div><p>This paper describes part of the activities conducted by RILEM Technical Committee 278-CHA (Crack-Healing of Asphalt Pavement Materials) Task Group 2a. The main objective of the TG2a was to explore and evaluate the experimental methods and criteria for the assessment of self-healing of asphalt binders. The work was developed in two phases. In the first phase, various existing healing test protocols were scrutinized, encompassing time-sweeps with single rest periods (TS-SRP), time-sweeps with multiple rest periods (TS-MRP), and linear amplitude sweeps with rest periods LASH). The protocols were evaluated and compared across different laboratories. The outcomes of interlaboratory testing led to the selection of the LASH-based approach. However, it was acknowledged that new insights and modifications were necessary due to the possible occurrence of biasing effects during the amplitude sweep. Such issues were addressed in the second phase of research, in which a modified LASH-based procedure underwent further investigation using various methods for data analysis, including approaches based on dissipated energy and the viscoelastic continuum damage model.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-025-02762-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144905230","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}