bluuebunny/crossref_metadata_2025 huggingface dataset:
Anatomycal, morphological and biochemical features of Pinus sibirica needles on recultivated and non-recultivated ash dump sites in the Middle Urals
Authors: Chukina Nadezhda , Lukina Natalia , Glazyrina Margarita , Filimonova Elena , Uchaev Anton , Nekrasova Olga
Published: September 2024

The article presents the results of anatomical, morphological and biochemical study of Pinus sibirica Du Tour needles of fly ash dumps and natural habitats in the Middle Urals. The study has shown that there was an increase in the area of resin ducts, as well as a decrease in the total nitrogen content in the needles of P. sibirica on ash dumps, compared with control habitats. An increase in the content of phenols and proline in the needles which indicates a response to stress, was also observed on the nonrecultivated ash dump unlike natural forest phytocenoses and recultivated ash dump. The revealed changes in the studied characteristics of P. sibirica needles are associated with the specific physico-chemical parameters of the technogenic substrate: an alkaline reaction of the medium as well as low content of clay particles and total nitrogen. Recultivation measures, namely covering the ash with strips of clay soil, contributed to the improvement of substrate parameters and the creation of more favorable conditions for plant growth.
Composition of woody plant litter in urbanized plant communities
Authors: Tsandekova Oxana
Published: September 2024

The article presents the analysis results of the litter composition of woody plants growing in urbanized plant communities. The research object was plant litter sampled under the canopy of such woody plants as Acer negundo L., Betula pendula Roth, Padus avium Mill. We determined the phytomass reserve and the level of nitrogen and phosphorus content in the litter of these tree species. The A. negundo litter had the most intense mineralization due to higher phytomass, nitrogen, and phosphorus accumulation in comparison with trees of the other species. The woody plants under study can be arranged in the following order as the analyzed indicators decrease: boxelder maple > bird cherry > silver birch. The experimental data can be used for biomonitoring studies of natural communities.
Floristic features of the Naryksky State Nature Reserve
Authors: Zueva Olga , Egorov Andrei , Tashev Alexander
Published: September 2024

Naryksky Reserve is located on lands within the boundaries of the Belovsky, Novokuznetsk, and Prokopyevsky municipal districts of Kemerovo Oblast. Three large mining companies are located near the reserve: LLC Resurs, LLC UK Kuzbassrazrezugol, and LLC Razrezdobycha Kuzbass. Studies have shown that 345 species from 204 genera and 67 families grow on the territory. The synanthropization coefficient of the flora is low and averages 3.9%. Four species are classified as invasive with status 2: Amoria hybrida, Conium maculatum, Pastinaca sativa, Plantago lanceolata. Three species grow on the territory of the reserve, included in the 3rd edition of the Red Book of the Kemerovo Oblast: Asarum europaeum, Erythronium sibiricum, Drosera rotundifolia L.
Materials for the moss flora of the Tomskaya Pisanitsa Museum-Reserve
Authors: Nozhinkov Alexei
Published: September 2024

The article provides a preliminary list of mossy species of the territory of the Tomskaya Pisanitsa Museum-Reserve. 36 species were found, including 4 liverworts and 32 leaf-stemmed mosses. The distribution of species by substrate types and growth forms is indicated.
Morphobiological features of Dracocephalum krylovii Lipsky in ex situ conditions in the Kuzbass Botanical Garden
Authors: Vronskaya Oksana
Published: September 2024

One of the methods of preserving the natural gene pool is its ex situ cultivation. For the first time he results of evaluation of morphobiological features of Dracocephalum krylovii at introduction were obtained in the Kuzbass Botanical Garden. The period of flowering and the sum of positive temperatures above 0 °C, effective temperatures above +5 °C, active temperatures above +10 °C, necessary for such phenophases as regrowth, budding, flowering, fruiting were determined as well as the initial stages of Dracocephalum krylovii’s development were studied. During the first year of growth of bions, latent and regenerative periods are distinguished. Under culture conditions an orthotropic elongated sprout is formed in the first year of life, the basal part of which is retracted into the soil and takes part in the construction of the underground perennial shoot structure
Features of the water regime of some species of the genus Dianthus L. in the South-Ural Botanical Garden (Ufa)
Authors: Reut Antonina , Uzyanbaeva Lyaysan
Published: September 2024

The results of studies of the characteristics of the water regime of 18 species of the genus Dianthus L. (D. acicularis, D. anatolicus, D. andrzejowskianus, D. borbassii, D. deltoides f. rubra, D. carthusianorum, D. chinensis, D. crossopetalus, D. giganteus, D. gratianopolitanus, D. hypanicus, D. japonicus, D. knappii, D. nardiformis, D. oshtenicus, D. plumarius, D. seguieri, D. uralensis) in the conditions of the South-Ural Botanical Garden-Institute of the UFRC RAS. The experiments were carried out during the growing seasons 2021–2023 on the basis of the laboratory of introduction and selection of flower plants. During the research, the seasonal dynamics of such water regime indicators as total water content, water-holding capacity and leaf water deficit were determined. The analysis of water regime parameters is based on the method of artificial wilting and the technique of saturation of plant samples. The obtained data were processed using standard statistical methods using Microsoft Excel 2003. It was revealed that as a result of the study, the studied taxa are characterized by high water-holding capacity. All of them are adapted to dry periods under cultivation conditions in the forest-steppe zone of the Bashkir Cis-Urals.
Future readiness of lime-based building materials: From heritage to innovation
Authors: Van Balen Koenraad
Published: September 2024

Construction materials that last more than 500 years, will last 500 years or more if applied today. Learning from the past and particularly from cultural heritage as a knowledge depository and inspiring solution database, has driven us not only to develop preservation strategies but also to develop innovative sustainable and lasting construction materials. In depth research of lime mortar-based constructions integrating todays scientific insights and tools, helps understanding processes of carbonation and their influence on behaviour of masonry. Questioning the paradigm that “modern” building materials developed in the beginning of the 20th century, developed insights on the value of traditional knowledge.
Functionalization of lime mortars and plasters: A biomimetic approach
Authors: Rodrígues-Navarro Carlos
Published: September 2024

Lime mortars and plasters have been used as building materials since the origins of pyrotechnology in the Levant ca. 12,000-14,000 years ago, and currently are experiencing a revival as compatible and sustainable materials in heritage conservation and modern construction. Extensive research has recently explored ways to improve their properties, particularly using Nature as an inspiration. Such a biomimetic approach is enabling the functionalization of lime mortars and plasters via different strategies that are reviewed here and include accelerated setting via enzymatic-like catalyzed carbonation, increased toughness via inter- and intracrystalline additive incorporation, modification of surface wettability and enhanced self-cleaning ability via surface microtexturing and photoactive nanoparticle incorporation, anti-biofouling capacity, increased radiative cooling, or self-healing properties.
Sustainable mortars and plasters from an industrial point of view
Authors: Oertel Tina
Published: September 2024

Sustainability has many facets. We will give insight into the development of sustainable mortars and renders using recycled limestone which attributes to the demand to increasingly replace raw materials from natural resources by recycled materials. Furthermore, we will present newly developed renders with improved thermal insulation properties as a necessity to keep heating energy in our buildings. All along the way, synergies are used by combining findings from university research projects, improvements of the raw materials industry und progress in the dry-mix mortar industry.
Durability of a lime-based rendering system exposed to different environmental conditions
Authors: Škondrić Marina , Zakić Dimitrije , Savić Savić , Topličić-Ćurčić Gordana , Vyšvařil Martin
Published: September 2024

Durability of lime-based mortars is a very interesting topic with many unknowns. The paper deals with the influence of wet-dry cycles, freeze-thaw cycles and exposure to soluble salt solutions on the composite samples consisting of one stone layer and two lime mortar rendering layers. Rendering mortars were composed of lime-putty as a binder, using river aggregate of two different gradations (0/4 mm and 0/0,5 mm) and two different lime:aggregate ratios (1:3 and 1:1) for inner and outer layer, respectively. After reaching the age of 90 days, samples were divided into five groups. Three groups were exposed to five cycles of wetting and drying. One group was exposed only to the deionized water action, another to the 10% NaCl solution, and the third group to the 10% Na2SO4 solution used only during the first cycle of wetting. The fourth group was exposed to four freeze and thaw cycles, while the final group was used as a reference. The results show that exposure to the wetting and drying cycles using water lead to the increase of the mechanical properties of the system, with pull-off strength 5.3 times higher when compared to the reference samples. Exposure to NaCl solution lead to almost unchanged behavior, while exposure to Na2SO4 solution lead to degradation during the final cycle of wetting and drying. Similarly, cracks occurred in the final cycle of the freeze-thaw test. After the finalization of tests, visual examination, XRF, XRD and SEM analysis were performed on the chosen tested samples.
Long-term mechanical properties of lime-pozzolan mortars: The role of amorphous Al2O3
Authors: Vyšvařil Martin , Žižlavský Tomáš , Dvořák Karel , Spychał Edyta
Published: September 2024

Today, lime-pozzolan mortars are being used in the repair of historic buildings, replacing the lime-cement mortars that were previously used in this practice, but were incompatible with historic mortars. It has been observed in laboratory research and also in practice that some lime-pozzolan mortars can lose strength over time. The cause of this behaviour is not fully understood, but the main reason seems to be the instability and breakdown of the aluminate phases. In this paper, the role of amorphous Al2O3 content in pozzolans on the long-term mechanical properties of lime-pozzolan mortars is studied. Lime-pozzolan mortars with 40% replacement of lime with pozzolans with different contents of amorphous Al2O3 (metakaolin, pumice, pozzolanic earth, trass, zeolite) were prepared and the changes in strength, porosity and mineralogical composition of the mortars (determined by XRD and TG/DTA) over time were monitored. Mortars containing pozzolans with a high content of amorphous Al2O3 (over 30% by weight) showed a dramatic decrease in strength, changes in porosity and a decrease in the content of monocarboaluminate (C4AcH11) with a simultaneous increase in the content of vaterite and aragonite. The negative effects of carbonation of the aluminate phases are particularly evident in pozzolans with a high content of amorphous Al2O3.
Material properties of building limes for pointing mortar for renovation and restoration of neo-Gothic churches in Sweden
Authors: Strandberg-de Bruijn Paulien , Balksten Kristin
Published: September 2024

During the neo-Gothic period of the 18th and 19th century, many churches in Sweden were built in brick and natural stone with a traditional lime-based mortar. Moisture- and salt related problems were common in these church buildings, already a few years after they were erected durability problems arose. Examples of these durability problems were internal salt precipitation, leaching of lime-based mortar and other moisture-related deterioration of mortar joints. When these neo-Gothic churches are repointed, this should be done with appropriate traditional lime mortars. However, since the introduction of cement as a material for mortars and renders, the knowledge on lime-based mortars has gradually decreased. Lime as a material for mortar, renders and plasters is still used, but only on a small scale and mostly for work on heritage buildings. There is a knowledge gap regarding material properties and workability of traditional limes. Therefore, the aim of this project was to determine the material properties of lime mortars used for restoration of churches built in brick or natural stone masonry.
Released heat of hydrating particle fractions of Portland cement
Authors: Reiterman Pavel , David Tomáš , Šmilauer Vít
Published: September 2024

Portland cement had belonged to the most used binder world-wide. Besides long tradition of its production, its specific technical properties are highly different in comparison with previous decades. Currently produced Portland cement exhibits similar mechanical properties, however the process of its hydration had slightly different character, inducing new challenges and technical difficulties during its use. The particle size distribution of currently produced cement is highly different in comparison with previous decades, because of optimized grinding process motivated by the reduction of related costs. Hence, the fines create the dominant part of current Portland cement. Present work follows previous research focused on the crack-resistant cement and confirmed direct influence of the fast kinetics of cement hydration on crack induction on drying. This paper deals with an experimental study focused on the hydration heat of selected particle fractions of Portland cement.
The influence of additives on the characteristics of earth-based mortar on the example of ancient stone structures in the Black Sea Basin
Authors: Sobczyńska Ewa , Garbacz Andrzej
Published: September 2024

The article describes the possible ways to modify the parameters of earth-based mortar used for the reconstruction of masonry structures on excavations located in the Black Sea area - archaeological site in Tyritake in Kerch on the Crimean Peninsula and Tanais near Rostov-on-Don in Russia. The structures we meet during these archaeological missions are irregular walls made of lime rock on earth-based mortar, which show a significant degree of disintegration due to the poor properties of the mortar and destructive atmospheric impacts. To carry out their reconstruction, it is necessary to select a mortar with appropriate parameters following conservation principles. Since earth-based mortar does not have sufficient characteristics, various possibilities for modification of its composition were considered, such as the addition of hydrated and hydraulic lime or cement. The compressive strength, adhesion, and durability parameters for unmodified and modified mortars were compared. Also, the issue of compatibility of the new reconstruction mortar with the existing stone material will be highlighted, which is crucial in the selection of material for the reconstruction of historic buildings.
A Research on Developing Zeolite Based Lime Mortars
Authors: Tuter Rukiye , Baccioglu Cem , Ozkan Cansel , Tanacan Leyla
Published: September 2024

Zeolites are aluminosilicate materials that possess a crystalline structure characterized by an interlinked three-dimensional framework of AlO4 and SiO4 tetrahedra. This framework contains open cavities in the form of channels and cages, leading to the designation of zeolites as molecular sieves. The characteristics of molecular sieves enable zeolites to have high adsorption capacity, ion exchange capability, and catalytic properties, which also contribute to improving indoor environmental quality. Zeolites also exhibit pozzolanic reactivity due to their high silica content. These chemical and physical properties of zeolites offer the potential to produce a lime-based mortar with improved mechanical performance, which can also contribute to the physical conditions of the environment with its hygroscopic behavior. For this purpose, under the scope of the research, the pozzolanic reactivity of zeolite obtained from the Manisa Gördes region of Türkiye has been evaluated first. After establishing the pozzolanic property of zeolite, mortar alternatives with different pozzolan/binder ratios, curing conditions, and aggregate sizes are investigated through a combination of physical and mechanical testing methods. Clinoptilolite-type natural zeolite in the form of powder and aggregates, which vary between 0-7 mm (0-2 mm, 2-4 mm, 4-7 mm) particle size, and class CL 90 – S type slaked lime were used to produce zeolite based lime mortars. The different particle sizes of zeolite aggregates were added to increase the moisture adsorption capacity of the mortar.
Analysis of mortar with brake lining waste by electrical impedance spectroscopy
Authors: Silva João B.L. Palma e , Silva Camila T. Ozaki e , Marçula Stephanie C. , Becker Ariane R. , Serna Pedro , Lintz Rosa C.C. , Gachet Luisa A.
Published: September 2024

Several researchers have been committed to developing multifunctional mortars, that is, beyond those usual purposes, such as laying masonry, coating, and sealing. These multifunctional mortars may be able to regenerate, store energy, and self-monitor, among other features. Some of these features involve the need to increase the electrical conductivity of the mortar. In this sense, a cement mortar was produced with gradual replacement of the sand with the brake lining waste, to evaluate the electrical impedance and phase angle in a frequency spectrum from 40 Hz to 100 kHz. The specimens had aluminum electrodes embedded in them to measure the properties in question, in the hardened state. This work is a complement to preliminary research that evaluated compressive strength and impedance only at a frequency of 60 Hz, in mortars with the same mix proportion. The results indicated that increasing the content of brake lining waste when replacing sand was able to reduce electrical resistance, both at low and high frequencies. This reduction was due to the increase in electrical conductivity caused by the composition of the brake lining waste, which gives the waste ohmic characteristics. In addition to improving electrical properties, the use of brake lining waste helps to reduce waste disposal in landfills, as well as reducing the consumption of natural aggregates.
Bacterially-promoted carbonation of lime-based building materials
Authors: Giordano Franco Grosso , Rodriguez-Navarro Carlos , De Belie Nele , Boon Nico
Published: September 2024

Lime-based binders, while historically significant, exhibit low strength and slow hardening, which has led to its replacement by cement. Hardening in lime-based materials occurs primarily through carbonation, whereby Ca(OH)2 reacts with atmospheric CO2 and produces CaCO3 cement. This study explores using bacterial additives to accelerate lime hardening by producing extra CO2. Three bacterial species were isolated and grown in liquid media. In a closed container, lime-mortar specimens were indirectly exposed to a cotton soaked in either bacterial suspension or water. Thermogravimetric analysis after 7 and 14 days indicated increased carbonation in cubes incubated with bacterial suspension, but not significantly. Subsequently, one bacterial suspension was mixed directly with lime. Progression of carbonation was tested with phenolphthalein and after 7, 14 and 21 days faster carbonation was seen in bacteria-containing pastes than those with only culture media. Overall, bacteria can carbonate lime materials but further optimization is needed for practical application.
Biobased mortars in the Mediterranean context: The contribution of the CUBÂTI project within cross-border cooperation
Authors: Fernandez Federica , Mensi Khitem , Campisi Tiziana , Colajanni Simona , Mamì Antonella , Nicolini Elvira , Saeli Manfredi , Germanà Maria Luisa
Published: September 2024

The Mediterranean context is a transition zone between the temperate and tropical belts, developing in some regions between 20° and 40° North and South latitude. Typical flora of the Mediterranean bush includes holm oak, cork oak, heather, myrtle, rosemary, laurel, oleander, orange, prickly pear, caper, and pistachio. The research carried out as part of the cross-border cooperation project CUBÂTI “Culture du bâti de qualité: recherche, innovation et entreprise pour la durabilité,” funded by the Italy-Tunisie Programme 2014-2020, identified some of these plant species, linked to production waste from the agro-food sector of Sicily and Tunisia, to experiment with new additives to be used as reinforcement in plaster mortars. Furthermore, with the objective of improving circular processes and reducing the use of natural resources, we preferred to use local binders that are not resource-intensive, such as gypsum and clay. The activities were conducted through intense collaboration between research institutes and manufacturing companies to intensify technological transfer and raise awareness towards the use of more environmentally sustainable materials. The results obtained from the experimentation, which included durability tests of the developed materials, demonstrated that the controlled addition of plant fibres could be a sustainable way to improve some performances of plaster mortars.
Exploring Lime Mortar Microstructure: Investigating the Impact of Mixed-in Additives and their Role in Salt Efflorescence Inhibition
Authors: Valdez Madrid Dulce Elizabeth , Winardhi Chandra Widyananda , De Belie Nele , Cnudde Veerle
Published: September 2024

This study presents the analysis of the crystallization impact in four lime-based mortar mixtures in order to determine the extent of decay during salt crystallization, affected by the use of additives and change in microstructure. For this purpose, non-destructive micro-computed tomography was used to monitor salt crystallization in lime mortar cores. This technique allowed tracking of salt precipitation after accelerated weathering steps and further enabled the localization of damage due to salt crystallization in both time and space. Results indicate that the internal 3D microstructure of the lime mortars is greatly influenced by the type and the amount of additive used. Polyacrylic acid (PAA) acted as a superplasticizer and air entrainer in the mixture, resulting in the formation of larger air voids, which led to a decrease in compressive strength. Mobilization of salts within the mortar matrix was observed, causing accumulation and cracking of the mortar wall towards the end of the weathering experiment.
Study of the influence of micro- and nano-cellulose on the growth and carbonation kinetics of portlandite crystals
Authors: García Lascurain Paulina Guzmán , Rodríguez-Navarro Carlos , De Giuli Irene , Toniolo Lucia , Goidanich Sara
Published: September 2024

Restoration of historical buildings contributes to the preservation of history and identity of the cities, but also, in the current climate crisis, an alternative solution to reduce the environmental impact of the construction sector, which is one of the main global contributors to green-house gas emissions and waste production. It can be also claimed that the most sustainable building is the one that has already been built. An important aspect to consider for the restoration of built heritage is the use of compatible materials, such as lime-based mortars, that should be preferred over cement. However, their slow setting and hardening (via carbonation), and, in some cases, poor durability prevent their full acceptance and widespread use. One course of action is to improve the quality of the binder via an innovative approach: inclusion of natural organic additives during the slaking process of CaO. This is expected to have a higher impact than their inclusion in the mortar’s mix design. In the present work the analysis of the growth of Ca(OH)2 crystals following their crystallization in the presence of micro- and nano-cellulose is studied, together with the morphological changes that these additives induce on portlandite crystals. Moreover, the study of the carbonation kinetics of the modified portlandite crystals gives insights on the effect that these additives have on the quality of the binder. The promising results highlight the potential of micro- and nano-cellulose as sustainable additives for lime-based binders. Furthermore, these additives can be obtained from industrial wastes, promoting a circular economy.
The design of a shaking table campaign on the out-of-plane response of masonry structures
Authors: Vecchio Dario , Colombo Carla , Vlachakis Georgios , Mendes Nuno , Lourenço Paulo B.
Published: September 2024

Despite the widespread presence in earthquake-prone areas, unreinforced masonry heritage buildings are significantly vulnerable to seismic events. Among the possible failures, the out-of-plane mechanism poses the greatest potential for collapse and involves inherent complexities. In particular, one-way and two-way bending are significantly recurrent yet not fully understood mechanisms, thus requiring further in-depth investigations. Such mechanisms can be idealized as single- or multi-rigid bodies experiencing rotational motions around two pivot points at the base. Albeit engineering applications are still limiting their approach to the use of static tools, the current research studies seek to forecast the dynamic behaviour of structures during the complete time history of any seismic actions. Nevertheless, it is apparent the necessity of experimental evidence to support the development of more advanced models capable of closely predicting the out-of-plane response. This paper presents the design of an extensive shaking table experimental campaign conducted at the Structural Laboratory of the University of Minho (Portugal), within the scope of the STAND4HERITAGE (New Standards for Seismic Assessment of Built Cultural Heritage) project. The campaign envisages the study of the dynamics of dry-joint masonry structures subjected to out-of-plane actions. The goal is to enlarge the experimental database currently available in the literature and to provide data for the validation of analytical and numerical models.
Towards a new method to estimate liquid redistribution coefficients in small fragments of mortar
Authors: Cambray Toby , Marincioni Valentina , Altamirano-Medina Hector
Published: September 2024

Inappropriate replacement mortars in historic buildings often lead to irreparable damage to historic masonry; the influence of the mortar on drying dynamics is crucial to these risks. The chemical and compositional analysis of historic mortar is widely practised for the purposes of formulation of replacement mortars but the compatibility, hygrothermal behaviour and moisture safety mainly depend on the physical properties. The chemistry and composition alone do not give a complete understanding of these functional properties, so physical measurements are necessary. However, it is often the case that only small fragments are available from existing walls due to the thickness of mortar joints, friability of the material and conservation constraints on removing material. While some physical properties lend themselves to measurement with small specimens (pore size distribution, sorption curves), liquid transport is harder to measure accurately for small (<25mm) irregular specimens. A new approach was proposed, combining several established techniques, allowing liquid redistribution to be estimated in such specimens. Specimens were subjected to drying experiments, without the usual constraints to approximate 1D flux (sealing the sides and bottom of a strictly prismatic specimen). The experiment was duplicated in 3D hygrothermal simulation, in which the liquid transport properties were adjusted until the simulation results closely approximated the experimental results. The method was demonstrated on cast cylinders of control materials, and will be developed to cover smaller, irregular pieces in subsequent work.
Automated construction of multi-leaf walls with natural stones
Authors: Wang Qianqing , dos Santos Ketson R. M. , Beyer Katrin
Published: September 2024

This paper introduces an innovative strategy for the construction of multi-leaf walls utilizing raw stones, a significant step forward in sustainable building practices. Our approach leverages advanced computational algorithms and image processing techniques to automatically build walls with irregular stones. By focusing on the physical assembly of these materials, the objective is to optimize their use in creating structurally robust walls. The core of our methodology lies in the efficient arrangement of irregular objects based on image-convolution techniques. The proposed packing algorithm is proven to be efficient and versatile in stacking stones without restriction in the shape and size of units. Evaluations of constructed walls based on geometric indices show that the stone layout meets masons’ rules-of-art. This work presents a scalable wall construction solution that could revolutionize the use of natural stones in construction.
Evaluation method for hygrothermal performance of masonry rendering mortars: Assessing moisture and mould growth risk under brazilian climate conditions
Authors: Cordeiro dos Santos Alexandre , Hamilton Becere Osmar
Published: September 2024

The presence of moisture in environments, when it exceeds certain limits and is associated with specific temperature ranges, can promote the growth of mould fungi inside buildings, compromising the health of occupants and leading to other harmful pathological manifestations affecting building performance. In this context, rendering mortars with paint application show significant potential to mitigate moisture ingress into building walls. This study aims to analyse normative trends related to criteria for water absorption by capillarity and resistance to vapour diffusion in masonry rendering mortars in Brazil. Additionally, we sought to identify gaps in existing standards and propose recommendations to enhance the suitability of rendering materials to the diverse climatic conditions found in the country. In this context, the results of the analysis of the hygrothermal behaviour of a wall rendering system are presented in this paper. The analysis, conducted through computational simulations, considered the climatic conditions of select Brazilian cities. Despite advancements in Brazilian standards, there are still gaps in existing norms regarding standardised criteria that allow for better selection of materials with performance compatible with their climatic context. The criteria outlined and the computational simulation method used were relevant in evaluating rendering materials under selected climatic conditions and have the potential to contribute to the development of more effective guidelines for the construction sector in Brazil.
Integrated Seismic and Energy Retrofitting of Masonry Elements Strengthened with PCM-enhanced GTRM/FRCM systems
Authors: FathiAzar Abbas , Zanjani Mahdi , Peralta Ignacio , Cattari Serena , De Angeli Silvia , Fachinotti Victor , Caggiano Antonio , Lagomarsino Sergio
Published: September 2024

The integration/combination of seismic and energy retrofit measures has been a subject of study for the past decade, exhibiting promising prospects. The main objective of these interventions is to mitigate seismic vulnerability while concurrently enhancing the energy performance and efficiency of new and existing buildings. Integrated approaches can hold the potential for substantial cost savings, time efficiency, and minimal disruption to occupants. The current body of literature emphasizes exploring the benefits of incorporating innovative methods/materials into conventional uncoupled retrofit initiatives. This study focuses on evaluating integrated measures at the panel scale for the prevalent Unreinforced Masonry (URM) typologies in Italy. A design framework has been introduced, aimed at enhancing the seismic capacity of buildings while concurrently improving energy efficiency through the integration of new materials (e.g., highly latent thermal energy storage systems achieved through the integration of Phase Change Materials - PCMs) into retrofit materials. To assess the reduction of the seismic vulnerability, the improvement of the shear strength is estimated by modifying the failure domains, while energy efficiency and thermal-energy storage enhancements are evaluated by using enthalpy-based theories, implemented into open-source software (i.e., FEM-based and through EnergyPlus). Thus, the design variables are those defined by the URM typologies, the adopted retrofitting technique, and the considered envelope. The adopted integrated (seismic and energy retrofitting) solutions will be compared with the standard reference one in terms of the energy consumed by the enclosed building to keep the indoor thermal comfort which also guarantees the target level of structural performance.
Out-of-plane strengthening of slender brickwork masonry partition walls with different types of glass fiber fabrics
Authors: Antolinc David , Klun Martin , Bosiljkov Vlatko
Published: September 2024

Non-structural masonry partition wall represents a relatively high risk for the occupants of the building even when subjected to the moderate earthquake loading due to its slenderness and brittle failure. The risk is higher for older public buildings where the non-structural partition walls are slenderer than in contemporary buildings and the importance of building is higher. Strengthening of the existing non-structural partition walls with glass fiber fabrics and façade meshes offers more sustainable option in comparison to their replacement by means of new drywall gypsum-card board walls and for that reason we conducted several out-of-plane cyclic tests to investigate the behavior of these walls in their weakest direction i.e. out-of-plane. All in all, eleven full scale partition walls were built with regular solid bricks and lime-cement mortar, where eight of them were strengthened with different glass fiber reinforcements and finally all tested under cyclic out-of-plane loading. The bond between the partition wall surface and reinforcing glass fiber fabric was ensured with the use of flexible polyurethane-based adhesive. Therefore, additional specially designed double leap shear-tensile test was conducted to evaluate the bond behavior. The bond between solid brick surface and glass fiber fabric tends to be stiffer in comparison to the option with glass fiber façade rendering mesh reinforcement. Results show that it is possible to provide a cost-effective improvement of the partition wall’s out-of-plane resistance by applying a simple glass fiber façade meshes with the use of flexible polyurethane adhesive.
Comparative study on stabilized oyster shells adobes: Mechanical resistance, durability and GHG emissions assessment
Authors: Arduin Deborah , Caldas Lucas Rosse , Claro Cristiana Costa , Rocha Fernando , Andrejkovicová Slávka
Published: September 2024

Adobes are earth bricks made without compression or firing in casts, usually using local soil. To improve adobe´s durability and mechanical behavior, the adobes allow the addition of various materials to stabilize them. This work compares the technical and GHG (greenhouse gas emissions) of adobes stabilized with potassium hydroxide, commercial lime Portland cement, and cement with hydrated lime, room-temperature cured. The adobe formulation was inspired by traditional mud adobes from the Aveiro region (Portugal), composed of silty clay loam local soil (80 wt.%), stabilized with wheat straw fibers (10 vol.%) and crushed oyster shells as filler, incorporating bio-based material. The adobe samples were assessed after 28 days of curing and after accelerated aging cycles. The mineralogy of the stabilized adobes after 28 days was determined through X-ray fluorescence (XRF) and X-ray diffraction (XRD) analysis. The attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) compared changes after aging cycles. Compressive strength and water erosion tests were performed to assess the stabilization and durability of the adobes. GHG emissions (kgCO2-eq.) of the mixes were provided through the life cycle assessment (LCA) methodology. The results indicate that the adequate type of stabilizer can change regarding the application of the adobes in the building. Lime and cement provided better compressive strength and durability, allowing a broader range of applications with higher GHG in comparison to KOH adobes, which presented restricted applications. This study contributes to encouraging the use of LCA along with durability assessment in earthen materials to promote sustainability in the construction sector.
Slag-based One-part Alkali-Activated Materials for Sustainable Constructions
Authors: Verza Edoardo , Bergamonti Laura , Michelini Elena , Ferretti Daniele , Bandini Simone , Laghi Luca , Aloysio Giulia De , Graiff Claudia
Published: September 2024

This work deals with the development of innovative cement-free plastering mortars with enhanced thermal properties. To this end, one-part alkali-activated slag-based materials were manufactured, by adding aluminum powder as expanding agent to reduce the density and expanded glass to improve thermal insulation. Different recipes were developed by varying the water content and the alkali-activator. The results show that the admixture containing sodium silicate meets the requirements for a lightweight plastering mortar in terms of mechanical strength (class CSII), despite exhibiting slightly elevated thermal conductivity with respect to that required for a type T2 (0.28 vs. 0.20 W/mK). The admixture with potassium silicate shows instead noteworthy values of both density and thermal conductivity, although its mechanical performance is very limited, due to its higher water content. Nevertheless, this last formulation could potentially serve as a viable starting point for the development of a sustainable cement-free construction material for the insulation of the building envelope. Further studies in this direction are currently underway.
Assessment of reinforced overlay for masonry retrofitting: Lime vs cementitious plaster
Authors: Scamardo Manuela , Cattaneo Sara , Crespi Pietro
Published: September 2024

Reinforced overlay is a very common retrofitting technique adopted in existing masonry buildings to improve their performance under seismic action, both in-plane and out-of-plane. The most traditional and widespread approach considers the use of cementitious mortar as plaster with steel meshes as reinforcement. However, cementitious materials may raise compatibility problems with the base material and sustainability issues, thus the use of lime mortar should be preferred. This paper presents the results of an experimental program aimed at assessing the contribution of the reinforced plaster strengthening system in increasing the load carrying capacity of masonry walls, comparing the performance of cementitious and lime mortar plaster. Cyclic diagonal compression tests were performed under displacement control. Unreinforced specimens were also tested as reference for the improvement evaluation. The results showed an improved performance with respect to the unreinforced ones for both the materials (cementitious and lime mortar), in terms of both strength and deformation capacity. The peak load seemed to be not significantly affected by the type of plaster, while higher displacement at the ultimate load was observed in case of lime mortar. Finally, an analytical method formulated to predict the strength of walls retrofitted with cementitious reinforced plaster was applied to check its validity also in case of lime-based plaster.
Characterization of a Bio-Composite Material (Natural Hydraulic Lime/Date Palm Leaflet) for Architectural Restoration
Authors: Kethiri Mohamed Aymen , Tedeschi Cristina
Published: September 2024

This scientific investigation aims to characterize the physical and mechanical properties of a new biomaterial designed for architectural restoration. The biomaterial studied is a composite of natural hydraulic lime (NHL) and date palm fibre. The study reports the first experimental characterization of these restorative materials. A series of mortar compositions were prepared with different particle size (0.5, 1, and 1.5 mm). The results showed that the mortars containing DPL exhibited significant changes in their properties due to variations in particle size. Increased DPLP led to lower density but whereas mechanical strength. This research provides valuable insights into the use of sustainable and renewable building materials, highlighting the benefits of exploiting agricultural waste in the constructional sector. The findings lay the groundwork for future research and innovation in environmentally friendly construction technologies.
Characterization of lime based insulating mortars for existing buildings in the EU market
Authors: Gómez Iborra Iker , Sanz Arauz David
Published: September 2024

There are several lime mortars which have been developed to improve the thermal performance of the facades of existing buildings. They are used as the final coating of a building’s facade thanks to their insulating capacities, weather resistance, vapour permeability, easy application, non-flat substrates adaptability, and/or masonry compatibility. Normally these mortars come into a system to achieve both thermal properties and weathering resistance. The thermally improved mortars, which are lime based, contain an important amount of insulating particles such as cork, diatomaceous earth, expanded clay, expanded perlite or vermiculite, mullite, aerated glass, aerogel, EPS, wood fibres or others. They also may contain pozzolanas and other cementitious particles. They also may contain additives in order to improve its mechanical resistances and/or elasticity. The weathering resistance mortar, the more external one, is suited to complete the mechanical and outdoor resistance properties that the insulated layer lacks. Some of these systems may be obliged to use glass fibre meshes and External Thermal Insulation Composite Systems (ETICS) anchors so they are not as suitable as wanted in historical buildings. In this abstract our main goals are: Acknowledge the reasons to use these mortars, define the multiple layer system that are normally used within these mortars, find which mortars are normally available to be bought in the European Union market, analyse their declared properties and composition, and enlist them according to their potential capacities. Thanks to this paper we will have a better knowledge of the possibilities of lime mortars as insulating material.
Characterization of ready-mixed plasters for the conservation of architectural heritage
Authors: Carangi Maria Cecilia , Corti Cristina , Rampazzi Laura , Tedeschi Cristina
Published: September 2024

Nowadays, the use of ready-mixed mortars is widespread in the choice of materials for the conservation of architectural heritage. These are dry mixtures, which contain binders, aggregates and additives and which require only the addition and mixing with water. Their use makes it possible to avoid errors in the ratios of the components, limits waste and guarantee a constant product quality. On the other hand, there are no standards that require the declaration of all the components in the mixture, which makes difficult to select the most appropriate materials to use on historical substrates. Indeed, the presence of certain additives could alter other properties of the mortars or increase the probability of developing forms of degradation. In addition, the mixtures on the market are frequently labelled as environmentally, human and animal health friendly; but the actual sustainability of these mixtures is difficult to ascertain, because there are still few companies that study the Life Cycle Assessment (LCA) and publish the Environmental Product Declaration (EPD) of their products. In order to deepen the knowledge of this class of materials, this study proposes the characterization of five ready-mixed plasters, all labelled green by the companies. Analyses (X-ray diffraction, infrared spectroscopy, thermal analysis) have been carried out firstly to assess the compatibility of the mixtures with historical materials, to compare the results obtained with what is stated by the companies in the product data sheets, and to assess whether, through routine laboratory analyses, it is possible to certify the sustainability of these materials.
Effects of Organic Additives on Portlandite Microstructure during CaO Hydration
Authors: Pesce Giovanni L. , Pesce Cecilia , Molinari Marco
Published: September 2024

This study evaluates the effect of various organic additives on the microstructure of portlandite crystals during the hydration of CaO. Calcium hydroxide mixed with selected additives was prepared and characterised in terms of crystal size and habit, platelets abundance, and particle size distribution using various techniques such as XRD, SEM and Particle Size Analysis. The results suggest that the microstructure of portlandite is altered by the presence of carbohydrates and sulfonates, showing higher platelets abundance, smaller crystallite size, and higher specific surface area. The presence of hydroxyl-rich carbohydrates induces more marked effects compared to sulfonates. These results show that it is possible to tailor the properties of lime to specific applications in both, the conservation and the construction industry. Furthermore, the results show that it is possible to enable the development of materials specifically dedicated to other applications such as the synthesis of precipitated calcium carbonate and the design of CO2 sorbents, all of which will have the added value of reducing the global anthropogenic CO2 emissions.
Experimental modal and FEM analysis of a historical building
Authors: Rinaldis Dario
Published: September 2024

The CEDRAV building in Cerreto di Spoleto, originally a monastery, was built in the 14th century on the top of a rock ridge. The two seismic events that occurred on September 26th, 1997, with magnitude Ms=5.4 and Ms=6, respectively, caused some damages to it, but the event occurred on 14 October 1997 caused the main damages. This study includes analyses mainly related to the part of the data acquired corresponding to tests and configurations using temporary deployments. The building is very complex and rigid. In fact, translational and torsional frequencies are close to one another, coupling occurs and damping ratio is low. Coupling of the frequencies and the low damping are two factors that cause beating effect when shaking is strong enough. For example, the approximate beating period is computed for the June 28th 2000 earthquake as (taking T1 = 1/9.7 = 0.104 s, and T2 = 1/10.4 = 0.096 s) Tb = 2.5 s, observable in the time history plots. On the basis of the experimental results obtained by means of temporary arrays, a permanent network was designed and installed, which recorded several seismic events. A preliminary analysis in frequency domain, based on the determination of auto and cross power spectral density, has been first performed; subsequently the modal structure identification by means of the Ibrahim time domain technique and the Frequency Domain Decomposition technique in the frequency domain, have been carried out. A frequency domain analysis of the structure has also been performed by means of the Frequency Response Function (FRF) analysis. The experimental results have been finally compared with those obtained from a FEM.