@article {523, title = {Concrete material science: Past, present, and future innovations}, journal = {Cement and Concrete Research}, volume = {Volume 112}, year = {2018}, month = {Oct-01-2018}, pages = {5-24}, abstract = {

Concrete is flying off, but it is simultaneously facing tremendous challenges in terms of environmental impact, financial needs, societal acceptance and image. Based on an historical approach of the science of concrete and reinforced concrete in particular, this paper calls for the exploration of radical changes in three key aspects of concrete use: reinforcement, binder content, and implementation methods. More precisely, it is suggested that, in parallel to the introduction of robotic fabrication methods, digital technologies may be key for the introduction several innovations like (i) rebar-free reinforcement using non-convex granular media; (ii) compression-optimized concrete structures, using topology optimization, architectural geometry, and 3D-printing or origami-patterned formworks; (iii) truly digital concrete through the coupling of massive data collection and deep learning.

CCR DIGITAL CONCRETE.pdf

Fig. 1. Top: Comparative evolution of the post-WWII global cement, steel, and plastic{\textellipsis}

Fig. 2. Top: The four beams on this figure have the same load bearing capacity

Fig. 3. (a): A {\textquotedblleft}deterministic{\textquotedblright} or regular Apollonian packing of disks in a circular{\textellipsis}

Fig. 4. A surface area vs particle size plot for the different granular populations -{\textellipsis}

Fig. 5. Minimum porosity of 17 different concretes, plotted vs the ratio between the{\textellipsis}

Fig. 6. Schematic illustration of the difference between an Apollonian packing (a) and{\textellipsis}

Fig. 7. Two perturbations occurring in a dense assembly of particles with at least two{\textellipsis}

Fig. 8. SEM images of cement pastes hydrated without (a and c) or with (b and d){\textellipsis}

Fig. 9. Binder intensity index as a function of 28days strength for close to one{\textellipsis}

Fig. 10. Entangled assemblages of non-convex particles which could provide{\textellipsis}

Fig. 11. Free-form architecture with UHPFRC concrete: (A) Curved panels of the Louis{\textellipsis}

Fig. 12. (A) Aircraft hangar, Orvieto, architect-engineer Pier Luigi Nervi, 1935; (B) A{\textellipsis}

Fig. 13. Cartoon depicting a paradigm for transformative evolution of research on{\textellipsis}

}, issn = {00088846}, doi = {10.1016/j.cemconres.2018.05.002}, url = {https://www.sciencedirect.com/science/article/pii/S0008884618300802}, author = {Henri Van Damme} } @article {620, title = {Earth concrete. Stabilization revisited}, journal = {Cement and Concrete Research}, volume = {114}, year = {2018}, month = {Dec-2018}, pages = {90 - 102}, abstract = {

Not surprisingly, with the increased awareness of environmental issues, construction with raw (crude, unbaked) earth (subsoil) is gaining renewed interest. However, it suffers from a poor image and from the difficulty to meet modern productivity standards and to pass some durability tests designed for industrial materials. The recent trend is to overcome these drawbacks by \“stabilizing\” the material most often with Portland cement (PC). Here we show that stabilization with PC is in general neither technically nor environmentally advisable. It brings only moderate mechanical improvement at a high environmental cost. Rather than massively transforming crude earth into a low quality concrete, it would be more appropriate to adapt the architectural practice and/or to look for milder ways to improve properties. In this respect, the recent successful attempts to improve the workability and the strength of raw earth by controlling the dispersion of its fine fraction seem to be particularly promising.

}, issn = {00088846}, doi = {10.1016/j.cemconres.2017.02.035}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0008884616308365}, author = {Henri Van Damme and Houben, Hugo} } @article {588, title = {From cellulose to kerogen: molecular simulation of a geological process}, journal = {Chemical Science}, volume = {8}, year = {2017}, month = {Dec-01-2017}, pages = {8325-8335}, abstract = {

The process by which organic matter decomposes deep underground to form petroleum and its underlying kerogen matrix has so far remained a no man\&$\#$39;s land to theoreticians, largely because of the geological (Myears) timescale associated with the process. Using reactive molecular dynamics and an accelerated simulation framework, the replica exchange molecular dynamics method, we simulate the full transformation of cellulose into kerogen and its associated fluid phase under prevailing geological conditions. We observe in sequence the fragmentation of the cellulose crystal and production of water, the development of an unsaturated aliphatic macromolecular phase and its aromatization. The composition of the solid residue along the maturation pathway strictly follows what is observed for natural type III kerogen and for artificially matured samples under confined conditions. After expulsion of the fluid phase, the obtained microporous kerogen possesses the structure, texture, density, porosity and stiffness observed for mature type III kerogen and a microporous carbon obtained by saccharose pyrolysis at low temperature. As expected for this variety of precursor, the main resulting hydrocarbon is methane. The present work thus demonstrates that molecular simulations can now be used to assess, almost quantitatively, such complex chemical processes as petrogenesis in fossil reservoirs and, more generally, the possible conversion of any natural product into bio-sourced materials and/or fuel.

}, issn = {2041-6520}, doi = {10.1039/C7SC03466K}, url = {http://xlink.rsc.org/?DOI=C7SC03466K}, author = {Atmani, Lea and Christophe Bichara and Roland Jean-Marc Pellenq and Henri Van Damme and Adri CT Van Duin and Raza, Zamaan and Truflandier, Lionel A. and Ama{\"e}l Obliger and Kralert, Paul G. and Franz-Josef Ulm and Jean-Marc Leyssale} } @book {636, title = {Springer Series in Geomechanics and GeoengineeringAdvances in Laboratory Testing and Modelling of Soils and Shales (ATMSS)Measurement of Mechanical Properties of Thin Clay Films and Comparison with Molecular Simulations}, series = {Springer Series in Geomechanics and Geoengineering}, year = {2017}, pages = {78-84}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, address = {Cham}, abstract = {

Here, we focus on the hydromechanical behavior of self-standing clay films with a thickness of a few dozen microns. We measure their elastic and creep properties and how those properties depend on the interlayer cation and on the relative humidity (or water content). Those experimental results are compared with the elastic and creep behavior of nanometric clay particles, which we characterize by molecular simulations. Significant qualitative differences between the behavior of the clay films and that of the clay particles are observed, which suggests that the hydromechanical behavior of the clay films is significantly impacted by their mesostructure (i.e., by how the clay particles or tactoids are arranged in space). Upscaling the hydromechanical behavior of the clay films from that of the clay particles may be challenging.

}, isbn = {978-3-319-52772-7}, issn = {1866-8755}, doi = {10.1007/978-3-319-52773-410.1007/978-3-319-52773-4_8}, url = {http://link.springer.com/10.1007/978-3-319-52773-4}, author = {Benoit Carrier and Matthieu Vandamme and Roland Jean-Marc Pellenq and Henri Van Damme}, editor = {Ferrari, Alessio and Laloui, Lyesse} } @article {217, title = {Effect of Water on Elastic and Creep Properties of Self-Standing Clay Films}, journal = {Langmuir}, volume = {32}, year = {2016}, month = {Feb-09-2016}, pages = {1370 - 1379}, abstract = {

We characterized experimentally the elastic and creep properties of thin self-standing clay films, and how their mechanical properties evolved with relative humidity and water content. The films were made of clay montmorillonite SWy-2, obtained by evaporation of a clay suspension. Three types of films were manufactured, which differed by their interlayer cation: sodium, calcium, or a mixture of sodium with calcium. The orientational order of the films was characterized by X-ray diffractometry. The films were mechanically solicited in tension, the resulting strains being measured by digital image correlation. We measured the Young\&$\#$39;s modulus and the creep over a variety of relative humidities, on a full cycle of adsorption-desorption for what concerns the Young\&$\#$39;s modulus. Increasing relative humidity made the films less stiff and made them creep more. Both the elastic and creep properties depended significantly on the interlayer cation. For the Young\&$\#$39;s modulus, this dependence must originate from a scale greater than the scale of the clay layer. Also, hysteresis disappeared when plotting the Young\&$\#$39;s modulus versus water content instead of relative humidity. Independent of interlayer cation and of relative humidity greater than 60\%, after a transient period, the creep of the films was always a logarithmic function of time. The experimental data gathered on these mesoscale systems can be of value for modelers who aim at predicting the mechanical behavior of clay-based materials (e.g., shales) at the engineering macroscopic scale from the one at the atomistic scale, for them to validate the first steps of their upscaling scheme. They provide also valuable reference data for bioinspired clay-based hybrid materials.

}, issn = {0743-7463}, doi = {10.1021/acs.langmuir.5b03431}, author = {Benoit Carrier and Matthieu Vandamme and Roland Jean-Marc Pellenq and Bornert, Michel and Ferrage, Eric and Hubert, Fabien and Henri Van Damme} } @article {247, title = {Evolution of organo-clay composites with respect to thermal maturity in type II organic-rich source rocks}, journal = {Geochimica et Cosmochimica Acta}, volume = {195}, year = {2016}, month = {Dec-15-2016}, pages = {68 - 83}, abstract = {

Among the proposed pathways of sequestration and progressive transformation of organic matter (OM) during burial, the sorptive protection mechanism explains the strong relationship between total organic carbon (TOC) and mineral surface area (MSA) noted in numerous black shales around the globe. The complete mechanistic framework of preservation and evolution of OM in organo-mineral complexes remains, however, an enigma. On one hand, smectite layers composing the clay fraction are known to have a major influence on available surface area. OM maturation occurs, on the other hand, concurrently with the smectite illitization that provokes the closure of the interlayer spaces. The potential of smectite layers in the sequestration and preservation of organic molecules and the fate of these molecules with respect to the smectite illitization were therefore addressed. Here, the mineralogy of three organic-rich source rocks of various maturities was characterized in regards with the geochemistry of their OM. A thorough examination of the clay minerals present in the clay matrices provided evidences of mixed layer minerals containing smectite and illite layers with an increasing illite component with respect to maturity. The comprehensive interpretation of the X-ray diffractograms and analytical electron microscopy results suggested the presence of organic molecules in the inter-particulate and possibly the interlayer spaces of the smectite-rich components in immature source rocks. This eventuality was further supported by the presence of intercalated clay-organic nanocomposites observed by transmitted electron microscopy coupled with energy dispersive spectroscopy. Textural observations also showed that the increased illite content found in the overmature sample led to the reorganization of the OM and the clay particles into nano-scale aggregates. These results clarify the geochemical mechanism beyond the reported relationship between TOC and MSA and allow generalizing it to various organic-rich source rocks. Eventually, the understanding of the close organo-clay association raises prospects on the prediction of the evolution of the mechanical properties of economically valuable source rocks with respect to maturity.

}, issn = {00167037}, doi = {10.1016/j.gca.2016.09.008}, author = {Berthonneau, Jeremie and Grauby, Olivier and Muhannad Abuhaikal and Roland Jean-Marc Pellenq and Franz-Josef Ulm and Henri Van Damme} } @proceedings {333, title = {Creep of Clay: Numerical Results at the Scale of a Layer and Experimental Results at the Scale of Thin Self-Standing Films}, journal = {10th International Conference on Mechanics and Physics of Creep, Shrinkage, and Durability of Concrete and Concrete StructuresCONCREEP 10}, volume = {CONCREEP 10: MECHANICS AND PHYSICS OF CREEP, SHRINKAGE, AND DURABILITY OF CONCRETE AND CONCRETE STRUCTURES }, year = {2015}, month = {Sep-17-2015}, pages = {531-536}, publisher = {American Society of Civil Engineers}, address = {September 21{\textendash}23, 2015, Vienna, AustriaReston, VA}, abstract = {

This work focuses on the creep of clay-based materials, which exhibit significant analogies with cement-based materials. Here, we studied the creep of clay at two scales and with two techniques: numerically (with molecular simulations) at the scale of a clay layer (nm), and experimentally at the scale of thin self-standing clay films (few dozen m). At the scale of the clay layer, numerical simulations showed that the shear rate was constant over time and an affine function of the shear stress. Creep experiments showed that, after a transient period, the creep function of our thin self-standing clay films was a logarithmic function of time. A comparison of the results obtained at the two scales shows that the origin of the logarithmic feature of clay creep must at least partly originate from a scale greater than that of an individual clay layer. By analogy, such result is likely to hold for cementitious materials, which are also known to creep logarithmically with respect to time in the long term: the origin of this logarithmic feature is likely to stem at least partly from a scale greater than the scale of an individual C-S-H layer.

}, doi = {10.1061/978078447934610.1061/9780784479346.064}, author = {Benoit Carrier and Matthieu Vandamme and Roland Jean-Marc Pellenq and Henri Van Damme}, editor = {Hellmich, Christian and Pichler, Bernhard and Kollegger, Johann} } @article {163, title = {Diffusion of Interlayer Cations in Swelling Clays as a Function of Water Content: Case of Montmorillonites Saturated with Alkali Cations}, journal = {The Journal of Physical Chemistry C}, volume = {119}, year = {2015}, month = {May-14-2015}, pages = {10370 - 10378}, abstract = {
Abstract Image

Swelling clays act as ion-exchange membranes owing to the presence of extra-framework ions surrounded by water molecules. A better understanding of the motion of the ions present in the pore space is required to predict the diffusion properties in these solids. Since water molecules tend to adsorb both on ions and clay surfaces, they moderate the interactions between the ions and the framework. The hydration of ions therefore has an impact on their diffusion properties. In this paper, the MX-80 montmorillonite considered for nuclear waste disposal applications has been selected and studied using an approach combining measurements of complex impedance spectroscopy and water adsorption isotherms. The number of charge carriers has been estimated, and the diffusion coefficient for interlayer cations at various hydration states was determined. The evolution of the diffusion coefficient is subsequently correlated with the effect of the opening of the interlayer space and its hydration state. The resulting picture sheds light on the reversible or irreversible character of ion exchange. Finally, our results obtained from the difference between the interlayer diffusion coefficients extracted from conductivity measurements and those obtained at the macroscopic scale is discussed in terms of the textural parameters.

}, issn = {1932-7447}, doi = {10.1021/jp512986d}, author = {Salles, Fabrice and Douillard, Jean-Marc and Bildstein, Olivier and El Ghazi, Samira and Prelot, B{\'e}n{\'e}dicte and Zajac, Jerzy and Henri Van Damme} } @article {162, title = {Fractal analysis of surface roughness of montmorillonite clay self-supported films: Effects of exchanged cations and of mechanical tensile stress}, journal = {Colloids and Surfaces A: Physicochemical and Engineering Aspects}, volume = {486}, year = {2015}, month = {Dec-05-2015}, pages = {38 - 44}, abstract = {

In this paper, surface roughness of self-supported montmorillonite clay films was studied by the use of fractal analysis to study its links with various inter-foliar cations, mechanical properties, and permeability. The Hurst exponent of fractional Brownian motion was estimated by maximum likelihood from optical images in reflection mode. Images corresponding to films with different inter-foliar exchanged cations visually show significant texture variations. It is confirmed by a continuous decrease of H parameter toward less correlated textures as one goes from the samples exchanged with monovalent ions to those exchanged with divalent and finally trivalent ions. The same films were analyzed while they were submitted to mechanical tensile stress. The films exchanged with the most charged cations or less hydrated ones do not show any evidence of texture change and the H parameter is almost constant. Concerning the permeability study, less permeable parent cakes \– with hydrated monovalent cations \– lead to relatively smooth and less disturbed surface films with high H parameter. In the opposite, very permeable cakes give birth to anti-persistent relief.

}, issn = {09277757}, doi = {10.1016/j.colsurfa.2015.09.001}, author = {Zabat, M. and Harba, R. and Henri Van Damme} } @article {185, title = {The Maya blue nanostructured material concept applied to colouring geopolymers}, journal = {RSC Adv.}, volume = {5}, year = {2015}, month = {Nov-2015}, pages = {98834 - 98841}, abstract = {

Maya blue is an ancient nanostructured pigment synthetized by assembling indigo, a natural dye, with palygorskite, a microfibrous clay mineral. The novelty of our approach is to mimic \“pre-Columbian nanotechnology\” and to functionalize geopolymers with a sepiolite-based hybrid organic\–inorganic nanocomposite inspired from the Maya blue. It is acid- and UV-resistant, as confirmed by the stability of Maya mural paintings over time. We synthesized analogous pigments, using methylene blue (MB) and methyl red (MR) as organic dyes and sepiolite as fibrous clay mineral. We used an aqueous and a solid-state method, both leading to encapsulation of dye monomers into the clay micropores, as confirmed by UV-vis spectroscopy. This nanostructured pigment was then included into a geopolymer matrix at room temperature. The stability of the new material to UV and acid was tested. It was confirmed that it is the prior encapsulation of the dye into sepiolite that leads to the stability of the pigment in the geopolymer matrix. This first study opens the way to numerous possibilities for functionalizing inorganic binder materials with organic elements that would be otherwise sensitive to thermal treatment in conventional ceramic processing.

}, doi = {10.1039/C5RA14076E}, author = {Ouellet-Plamondon, Claudiane and Aranda, Pilar and Favier, Aur{\'e}lie and Habert, Guillaume and Henri Van Damme and Ruiz-Hitzky, Eduardo} } @article {114, title = {Elastic Properties of Swelling Clay Particles at Finite Temperature upon Hydration}, journal = {Journal of Physical Chemistry C}, volume = {118}, year = {2014}, month = {May-01-2014}, pages = {8933-8943}, type = {Article}, abstract = {
Abstract Image

The knowledge of mechanical properties of swelling clays on the scale of the clay layer is of crucial importance to build predictive hydromechanical macroscopic constitutive laws in a bottom-up approach. In this work, we computed the elastic properties of particles of a swelling clay (i.e., montmorillonite) by molecular dynamics simulations. Because of the softness of the material in the direction orthogonal to the clay layer with increasing water content, the computation of the whole stiffness tensor was not trivial: we needed to implement the elastic bath method,1 which allows us to attenuate thermal strains and compute the stiffness via strain fluctuations in isothermal\–isobaric simulations. We investigated the effect of water content, temperature, and the interlayer cation on the elastic properties of swelling clays. In particular, we showed that the out-of-plane stiffness coefficients computed at 300 K differed significantly from the same coefficients computed at 0 K. The out-of-plane coefficients were very sensitive to both temperature and water content. In contrast, the dependence of the in-plane coefficients to temperature was slight. Moreover, the decrease of the in-plane coefficients with water content could be entirely explained by the change of geometry of the system due to the swelling of the interlayer space. The interlayer cation impacted the elastic properties of montmorillonite only in the driest states.

}, issn = {1932-7447}, doi = {10.1021/jp412160e}, author = {Benoit Carrier and Matthieu Vandamme and Roland Jean-Marc Pellenq and Henri Van Damme} } @article {46, title = {ESEM Study of the Humidity-Induced Swelling of Clay Film}, journal = {Langmuir}, volume = {29}, year = {2013}, month = {Oct-02-2013}, pages = {12823{\textendash}12833}, abstract = {
Abstract Image

We measured the humidity-induced swelling of thin self-standing films of montmorillonite clay by a combination of environmental scanning electron microscopy (ESEM) and digital image correlation (DIC). The films were about 40 \μm thick. They were prepared by depositing and evaporating a suspension of clay and peeling off the highly oriented deposits. The rationale for creating such original samples was to obtain mesoscopic samples that could be used to bridge experimentally the gap between the scale of the clay layer and the engineering scale of a macroscopic clay sample. Several montmorillonite samples were used: the reference clay Swy-2, the same clay homoionized with sodium or calcium ions, and a sodium-exchanged Cloisite. The edges of the clay films were observed by ESEM at various relative humidity values between 14\% and 95\%. The ESEM images were then analyzed by DIC to measure the swelling or the shrinkage of the films. We also measured the adsorption/desorption isotherms by weighing the film samples in a humidity-controlled environment. In order to analyze our results, we compared our swelling/shrinkage and adsorption/desorption data with previously published data on the interlayer spacing obtained by X-ray diffraction and with numerical estimates of the interlayer water obtained by molecular dynamics simulation. The swelling and the hysteresis of this swelling were found to be comparable for the overall macroscopic films and for the interlayer space. The same correspondence between film and interlayer space was observed for the amount of adsorbed water. This suggests that, in the range of relative humidities values explored, the films behave like freely swelling oriented stacks of clay layers, without any significant contribution from the mesoporosity. The relevance of this result for the behavior of clayey sedimentary rocks and the differences with the behavior of nonoriented samples (powders or compacted powders) are briefly discussed.

}, doi = {10.1021/la402781p}, author = {Benoit Carrier and Wang, Linlin and Matthieu Vandamme and Roland Jean-Marc Pellenq and Bornert, Michel and Tanguy, Alexandre and Henri Van Damme} }