Publicacións

@article{rodriguez-alvaro_rheology_2025,

title = {Rheology and setting of self-compacting concrete incorporating high volume of fly ash and internal curing via coal and wood bottom ash},

author = {Roberto Rodríguez-Álvaro and Sindy Seara-Paz and Fernando Martínez-Abella and Belén González-Fonteboa},

url = {https://www.sciencedirect.com/science/article/pii/S2352710225016638},

doi = {10.1016/j.jobe.2025.113426},

issn = {2352-7102},

year  = {2025},

date = {2025-10-01},

urldate = {2025-10-01},

journal = {Journal of Building Engineering},

volume = {111},

pages = {113426},

abstract = {The continuous development of innovative high performance concretes is encouraging the use of new and sophisticated techniques to study their performance. In this article, a rheometer is used to determine the rheological parameters (dynamic yield stress, viscosity, yield stress at rest and thixotropy) of an internally cured self-compacting concrete with fly ash blended cement. This research is motivated by the scarcity of rheological studies regarding internally cured concretes. Coal bottom ash (CBA) and wood bottom ash (WA) were used as internal curing water reservoirs. Air content, setting times and temperature rise under semi-adiabatic conditions were also analysed. The results indicate that ball bearing effect of fly ash decreased the amount of high range water reducer admixture added to the mortars to get similar workability. Furthermore, all the rheological parameters increased when using coal bottom ash and, more remarkably, wood ash, due to their irregular shape, rough texture and some minor water absorption. Internal curing of fly ash blended cement concrete has no detrimental effects on the fresh state properties, but special attention must be paid to the pre-wetting of porous aggregates. If the internal curing water reservoirs are wetted below their water absorption capacities, their use reduces workability and setting times. Therefore, the practicality of the proposed mixtures relay mainly on the care taken during their design and materials conditioning. The future research efforts should focus on the development of new mixes with different supplementary cementitious materials and new conditioning techniques that guarantee a precise pre-wetting.},

keywords = {Internal curing, Shear thickening, Thixotropy, Viscosity, Yield stress},

pubstate = {published},

tppubtype = {article}

}

@article{rojo-lopez_effect_2024,

title = {Effect of aggregate content and fibre type on the rheological behaviour and structural build-up of fibre reinforced self-compacting concrete using two binder compositions},

author = {Gemma Rojo-López and Belén González-Fonteboa and Fernando Martínez-Abella and Sindy Seara-Paz},

url = {https://www.sciencedirect.com/science/article/pii/S0950061824026321},

doi = {10.1016/j.conbuildmat.2024.137490},

issn = {0950-0618},

year  = {2024},

date = {2024-09-01},

urldate = {2024-09-01},

journal = {Construction and Building Materials},

volume = {442},

pages = {137490},

abstract = {Many parameters influence the fresh behaviour of fibre reinforced self-compacting concrete (FRSCC), such as length, aspect ratio, fibre content, solid volume fraction, and particle interaction. Most studies did not analyse rheological behaviour (just workability) and they are focused on paste or mortar. However, the analysis at the concrete level is also required to confirm the behaviour when the coarse aggregates and fibres are employed. This kind of analysis is scarce in the literature. Hence, this work aims to increase the knowledge about the effect of aggregate content and fibre type on FRSCC. To do so, the behaviour of self-compacting mixes with three different aggregate contents (550, 500, and 650 l/m3), two cementitious systems (100 % cement, and 60 % cement, 25 % limestone filler and 15 % metakaolin), and three different types of rigid fibres (two metallic and one polypropylene) were analysed. To characterise the concrete rheological performance, the stress growth test (SGT) was selected to avoid any fibre orientation. SGT was repeated twice under undisturbed and disturbed conditions to assess the structural build-up of the concrete. The results indicate that there is a critical value of the relative packing fraction that, once overcome, severely affects the fresh behaviour of FRSSC. This critical value can be calculated as the ratio between random loose packing fraction and dense packing fraction. It can be used to design a FRSCC mix guaranteeing that the fresh state remains in a suitable range where the hydrodynamic interactions dominate the behaviour and therefore, changes in the mix composition will not sharply modify the rheological performance of the concrete.},

keywords = {Packing fraction, Polypropylene, Rheology, Thixotropy},

pubstate = {published},

tppubtype = {article}

}

@article{di_mundo_masonry_2020,

title = {Masonry and render mortars with tyre rubber as aggregate: Fresh state rheology and hardened state performances},

author = {Rosa Di Mundo and Sindy Seara-Paz and Belén González-Fonteboa and Michele Notarnicola},

url = {https://www.sciencedirect.com/science/article/pii/S0950061820303640},

doi = {10.1016/j.conbuildmat.2020.118359},

issn = {0950-0618},

year  = {2020},

date = {2020-06-01},

urldate = {2026-08-06},

journal = {Construction and Building Materials},

volume = {245},

pages = {118359},

abstract = {This work shows how it is possible to tailor cement-rubber composites suitable as renders and masonry mortars with a reduced liquid water absorption. Recycled tyre rubber is used as aggregate in mixture with siliceous sand and its content is tuned in order to limit depletion of mechanical properties and, at the same time, ensure a sufficiently massive utilization of this secondary raw material. An extended investigation of the properties both at the fresh and hardened state is conducted. We show that presence of rubber sensitively reduces fluidity (hence workability) of the mortar. In particular, rubber modifies rheological properties such as thixotropy and dynamic torque, while does not affect viscosity. Overall, the fresh state properties are compatible with the casting and application of these mortar typologies, even for the highest rubber content (20–25% by volume). This rubber content is shown to be sufficient to ensure, just after few days of curing, an almost complete abatement of water drop absorption, specific functionality of these novel and more sustainable mortars.},

keywords = {Hydrophobic, Masonry mortar, Plasters/renders, Recycled tyre rubber, Rheology, Thixotropy, Viscosity, Water absorption, Water contact angle, Workability},

pubstate = {published},

tppubtype = {article}

}