Journal: Materials and Structures

Abbreviation

Mater Struct

Publisher

Springer

Journal Volumes

ISSN

1359-5997
1871-6873

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Publications1 - 10 of 92
  • Glued-in-rod timber joints: analytical model and finite element simulation
    Item type: Journal Article
    Hassanieh, Amirhossein; Valipour, Hamid R.; Bradford, Mark A.; et al. (2018)
    Materials and Structures
  • Chloride binding by layered double hydroxides (LDH/AFm phases) and alkali-activated slag pastes: an experimental study by RILEM TC 283-CAM
    Item type: Journal Article
    Gluth, Gregor J.G.; Mundra, Shishir; Henning, Ricky (2024)
    Materials and Structures
    Chloride binding by the hydrate phases of cementitious materials influences the rate of chloride ingress into these materials and, thus, the time at which chloride reaches the steel reinforcement in concrete structures. Chloride binding isotherms of individual hydrate phases would be required to model chloride ingress but are only scarcely available and partly conflicting. The present study by RILEM TC 283-CAM ‘Chloride transport in alkali-activated materials’ significantly extends the available database and resolves some of the apparent contradictions by determining the chloride binding isotherms of layered double hydroxides (LDH), including AFm phases (monosulfate, strätlingite, hydrotalcite, and meixnerite), and of alkali-activated slags (AAS) produced with four different activators (Na2SiO3, Na2O·1.87SiO2, Na2CO3, and Na2SO4), in NaOH/NaCl solutions at various liquid/solid ratios. Selected solids after chloride binding were analysed by X-ray diffraction, and thermodynamic modelling was applied to simulate the phase changes occurring during chloride binding by the AFm phases. The results of the present study show that the chloride binding isotherms of LDH/AFm phases depend strongly on the liquid/solid ratio during the experiments. This is attributed to kinetic restrictions, which are, however, currently poorly understood. Chloride binding by AAS pastes is only moderately influenced by the employed activator. A steep increase of the chloride binding by AAS occurs at free chloride concentrations above approx. 1.0 M, which is possibly related to chloride binding by the C–(N–)A–S–H gel in the AAS.
  • M&S highlight: Jensen and Hansen (1995), A dilatometer for measuring autogenous deformation in hardening Portland cement paste COMMENT
    Item type: Other Journal Item
    Lura, Pietro; Kovler, Konstantin (2022)
    Materials and Structures
  • Micromachining of hardened Portland cement pastes using femtosecond laser pulses
    Item type: Journal Article
    Trtik, P.; Hauri, C.P. (2007)
    Materials and Structures
  • Statistical investigation of two different interlayer shear test methods
    Item type: Journal Article
    Santagata, Felice A.; Ferrotti, Gilda; Partl, Manfred N.; et al. (2009)
    Materials and Structures
  • Impact of rapid-hardening cements on mechanical properties of cement bitumen emulsion asphalt
    Item type: Journal Article
    Xing, Fang; Garcia, Alvaro; Winnefeld, Frank; et al. (2016)
    Materials and Structures
  • Influence of cement content and environmental humidity on asphalt emulsion and cement composites performance
    Item type: Journal Article
    García, Alvaro; Lura, Pietro; Partl, Manfred N.; et al. (2013)
    Materials and Structures
  • Recommendation of RILEM TC 271-ASC: New accelerated test procedure for the assessment of resistance of natural stone and fired-clay brick units against salt crystallization
    Item type: Journal Article
    Lubelli, Barbara; Rörig-Daalgard, I.; Aguilar, A.M.; et al. (2023)
    Materials and Structures
    This recommendation is devoted to testing the resistance of natural stone and fired-clay brick units against salt crystallization. The procedure was developed by the RILEM TC 271-ASC to evaluate the durability of porous building materials against salt crystallization through a laboratory method that allows for accelerated testing without compromising the reliability of the results. The new procedure is designed to replicate salt damage caused by crystallization near the surface of materials as a result of capillary transport and evaporation. A new approach is proposed that considers the presence of two stages in the salt crystallization test. In the first, the accumulation stage, salts gradually accumulate on or near the surface of the material due to evaporation. In the second, the propagation stage, damage initiates and develops due to changes in moisture content and relative humidity that trigger salt dissolution and crystallization cycles. To achieve this, two types of salt were tested, namely sodium chloride and sodium sulphate, with each salt tested separately. A methodology for assessing the salt-induced damage is proposed, which includes visual and photographical observations and measurement of material loss. The procedure has been preliminarily validated in round robin tests.
  • Load-deformation behaviour of weft-knitted textile reinforced concrete in uniaxial tension
    Item type: Journal Article
    Lee, Minu; Mata Falcón, Jaime; Kaufmann, Walter (2021)
    Materials and Structures
    Weft-knitted textiles offer many advantages over conventional woven fabrics since they allow the fabrication of doubly curved geometries without the need of stitching multiple patches together. This study investigated the use of high-strength continuous fibres as knitted textile reinforcement, focusing on various knitting patterns, fibre materials, coating types and spatial features to enhance the bond conditions between concrete and reinforcement. The bond is of particular interest since the contact surface of knitted textiles is fundamentally different due to their closed surface, compared to commercially available textile reinforcement, which is normally formed as orthogonally woven grids of rovings. An experimental campaign consisting of 28 textile-concrete composites was conducted, where digital image correlation-based measurements were used to assess the load-deformation behaviour and to analyse the crack kinematics. The results showed a beneficial post-cracking behaviour for epoxy coated configurations with straight inlays. The comparison of these configurations with conventional textile reinforcement generally showed a similar behaviour, but with higher utilisation compared to the filament strength. The Tension Chord Model, which assumes a constant bond stress-slip relationship, was adapted for the specific geometry of the knitted reinforcement, and it was used for the estimation of bond stresses and a post-diction of the experimental results, generally showing a good agreement.
  • Effect of sulfidic mine tailings used as mineral admixtures on the hydration of common and alternative cements
    Item type: Journal Article
    Pires Martins, Natalia; Helser, Jillian; Plötze, Michael; et al. (2024)
    Materials and Structures
    In this work, we investigate the use of pyrite-rich tailings from an operational mine as mineral admixture in different cement matrices [Portland cement, calcium aluminate cement (CAC), and calcium sulfoaluminate cement (CSA)]. Hydration and microstructure changes were studied on cement pastes produced with a 30 wt% replacement of cement with tailings, up to 200 days. Based on our results, the effect of the tailings on the hydration of Portland cement is limited to a physical effect, and no sulfide-induced degradation is observed. In the CAC and CSA pastes, minor mineral phases present in the tailings chemically react, leading to changes in the mineral phase composition of CAC and CSA hydrated pastes. In addition, in all cement pastes studied, and more effectively in the CSA pastes, most of the metal(loid)s contained in the tailings were safely immobilized. Cement chemistry notation: C: CaO; A: Al2O3; F: Fe2O3; S: SiO2; S̅: SO3; c: CO2; H: H2O.
Publications1 - 10 of 92