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In conservation science the demand of multifunctional green materials displaying water repellency, consolidation, resistance to organic pollutants and pigments is constantly increasing. This research developed a green nanocomposite exhibiting photocatalytic, hydrophobic, consolidation and self-cleaning properties. This was achieved by synthesizing a TiO2 photocatalyst enriched with carbon dots (C-dots) and successfully incorporated into a tetraethoxysilane nanocomposite modified with nano-calcium oxalate and polydimethylsiloxane. The TiO2/C-dots that were prepared with a simple, low temperature, cost-effective and large-scale procedure were assessed via analytical and spectroscopic techniques and were resulted in anatase structure ranging in size from 10 to 40 nm. Photooxidation measurements displayed that TiO2/C-dots nanoparticles could photodegrade completely Methyl Orange (MO) under UV and visible irradiation after 120 min. The photocatalytic performance of the nanocomposite with TiO2/C-dots resulted promising under UV after longer irradiation time. The degradation of MO was faster on bulk xerogels containing the TiO2/C-dots than the corresponding ones with TiO2. The treatment of concrete, limestone and lime mortars with the nanocomposite proved to be compatible with the substrates in terms of aesthetical aspects. This study demonstrates encouraging potential for large-scale production of a multifunctional protective composite that offers hydrophobicity, self-cleaning properties and consolidation to architectural surfaces.
Dimitrios Stefanakis; Themis Krasoudaki; Anastasios-Ioannis Kaditis; Asterios Bakolas; Pagona-Noni Maravelaki. Design of Novel Photocatalytic Films for the Protection of Architectural Surfaces via the Incorporation of Green Photocatalysts. Coatings 2021, 11, 934 .
AMA StyleDimitrios Stefanakis, Themis Krasoudaki, Anastasios-Ioannis Kaditis, Asterios Bakolas, Pagona-Noni Maravelaki. Design of Novel Photocatalytic Films for the Protection of Architectural Surfaces via the Incorporation of Green Photocatalysts. Coatings. 2021; 11 (8):934.
Chicago/Turabian StyleDimitrios Stefanakis; Themis Krasoudaki; Anastasios-Ioannis Kaditis; Asterios Bakolas; Pagona-Noni Maravelaki. 2021. "Design of Novel Photocatalytic Films for the Protection of Architectural Surfaces via the Incorporation of Green Photocatalysts." Coatings 11, no. 8: 934.
Natural hydraulic lime (NHL) is a material which has received increased interest in the past decade as a binder for the production of mortars. The renewed interest of researchers and builders in natural hydraulic lime is attributed to its enhanced compatibility with many traditional materials, as well as the fact that it is an environmentally friendly material, especially in relation to modern cement. In the present study, two different types of natural hydraulic lime mortars are studied, using NHL2 and NHL3.5 as binder (in accordance to the new classification EN 459-1:2010) and the same river sand, while the influence of different binder to aggregate ratios on mortar characteristics is also investigated. Fresh mortar characteristics are examined immediately after mixing, while hardened mortar characteristics are evaluated at different mortar ages. Specifically, the mechanical performance of the mortars is evaluated through flexural and compressive strength tests, as well as the dynamic modulus of elasticity, which is estimated through ultrasound pulse velocity measurements. Physical performance of the mortars is investigated through the examination of the pore network structure characteristics, via mercury intrusion porosimetry measurements, and through the examination of hygric characteristics, via water absorption tests. The binder to aggregate ratio seems to play an important role in the development of the mechanical and physical characteristics of the mortars, while it influences mortar properties differently according to the type of the binder.
Maria Apostolopoulou; Asterios Bakolas; Meletis Kotsainas. Mechanical and physical performance of natural hydraulic lime mortars. Construction and Building Materials 2021, 290, 123272 .
AMA StyleMaria Apostolopoulou, Asterios Bakolas, Meletis Kotsainas. Mechanical and physical performance of natural hydraulic lime mortars. Construction and Building Materials. 2021; 290 ():123272.
Chicago/Turabian StyleMaria Apostolopoulou; Asterios Bakolas; Meletis Kotsainas. 2021. "Mechanical and physical performance of natural hydraulic lime mortars." Construction and Building Materials 290, no. : 123272.
During the past few years, the construction industry is looking to expand the use of ecological materials, in order to create environmentally friendly buildings, contributing to the sustainability of built environment and limiting the waste of energy. In this direction, earth is seriously reconsidered as a possible building material of extensive use. Additionally, earthen mortars are globally an extremely common type of contemporary and traditional mortar on account of the availability of earth material, its good thermal properties and low embodied energy. However, the main disadvantage of earthen mortars lays in their reduced resistance against water action. In the present paper, the use of natural hydraulic lime (NHL3.5) and ladle furnace slag (LFS) is investigated for the stabilization of earthen mortars, aiming to enhance their water resistance. Different mortar mixes, including stabilized and non-stabilized earthen mortars, are examined in relation to their chemical properties (thermal analysis, DTA/TG), microstructural characteristics (mercury intrusion porosimetry, water uptake tests), and mechanical properties (flexural and compressive strength tests, ultrasound pulse velocity measurements). Shrinkage of the different mortars is also monitored and assessed. Finally, the mortars are subjected to wetting-drying cycles to determine the effect of the stabilizing agents on the mortars’ resistance against water. The results show that both NHL3.5 and LFS, present an excellent stabilizing efficiency, enhancing earthen mortars’ resistance against water, while simultaneously improving their physico-chemical and mechanical characteristics.
Konstantinos Stathopoulos; Maria Apostolopoulou; Asterios Bakolas. Enhancement of water resistance of earthen mortars through stabilization. Construction and Building Materials 2021, 289, 123180 .
AMA StyleKonstantinos Stathopoulos, Maria Apostolopoulou, Asterios Bakolas. Enhancement of water resistance of earthen mortars through stabilization. Construction and Building Materials. 2021; 289 ():123180.
Chicago/Turabian StyleKonstantinos Stathopoulos; Maria Apostolopoulou; Asterios Bakolas. 2021. "Enhancement of water resistance of earthen mortars through stabilization." Construction and Building Materials 289, no. : 123180.
Contemporary artists experimented with a wide range of techniques as it is photography, combined with other materials so as to create images on various surfaces. Nikos Kessanlis (1930–2004), an eminent Greek artist, used photographic and mechanical techniques, involving the application of a photosensitive emulsion on different supports for his artistic creations. This photomechanical technique is called alternative printing. The present study examines a series made by Kessanlis in 1999–2000, composed of eleven panels of photosensitized canvases with the scope to identify the materials used by the artist (canvas, primer, photographic emulsion, protective layer), to understand the artist’s technique and to document the panels overall condition. The series is examined using non-invasive techniques (portable digital optical microscope) and analysis of micro-samples by–micro-Raman spectrometry. Micro-Raman analysis results identified the support, as canvas made by cotton and jute, the primer layer as a combination of titanium white and calcium carbonate and finally the photosensitized layer, as a gelatin silver chloride emulsion. Also further compounds are detected such is silver sulfide, related to the photosensitized emulsion deterioration and soot and lignin, related to the impure environment (air flow inside the metro station) where the series are on display for the last twenty years (Athens metro station). Finally, measurements of air temperature and relative humidity are also performed for a short period near the panels so as to evaluate the environmental conditions of the area. The results have shown extreme daily fluctuations of both factors, characterized by “cycling” that could be related to mechanical and chemical deterioration factors affecting the artwork condition.
Eugenia Stamatopoulou; Manto Sotiropoulou; Maria Karoglou; Asterios Bakolas. Characterization of contemporary artworks made on photosensitized canvas by means of optical microscopy and micro-Raman spectroscopy techniques. Microchemical Journal 2021, 165, 106110 .
AMA StyleEugenia Stamatopoulou, Manto Sotiropoulou, Maria Karoglou, Asterios Bakolas. Characterization of contemporary artworks made on photosensitized canvas by means of optical microscopy and micro-Raman spectroscopy techniques. Microchemical Journal. 2021; 165 ():106110.
Chicago/Turabian StyleEugenia Stamatopoulou; Manto Sotiropoulou; Maria Karoglou; Asterios Bakolas. 2021. "Characterization of contemporary artworks made on photosensitized canvas by means of optical microscopy and micro-Raman spectroscopy techniques." Microchemical Journal 165, no. : 106110.
Decision making for cultural heritage protection is a multi-criteria process, involving many parameters and stakeholders. In this paper is proposed a methodological approach, for the scientific support to decision making, based on advanced software programming interfaces (Matlab and Python). As a case study, the consolidation intervention was selected. Starting point of the proposed methodology is the use of integrated documentation protocols, as a source of the required data for the monument/ object of art, capable of feeding the decision-making system with standard quality/critical parameters and risk indicators. These data are both bibliographic and real experimental values, coming from research in laboratory conditions, as well as from pilot conservation applications on monument scale. The evaluation of the crucial criteria is performed by the "experienced user/ expert" and is thus exploited by the system to adapt their weight factors through mathematical models. Main characteristics of the proposed systems is that is easy to implement, has the ability to expand to other conservation interventions, and it is executable on/compatible with different operating systems, provides a qualitative evaluation of the result.
A. Kioussi; M. Karoglou; E. Protopapadakis; A. Doulamis; E. Ksinopoulou; A. Bakolas; A. Moropoulou. A computationally assisted cultural heritage conservation method. Journal of Cultural Heritage 2021, 48, 119 -128.
AMA StyleA. Kioussi, M. Karoglou, E. Protopapadakis, A. Doulamis, E. Ksinopoulou, A. Bakolas, A. Moropoulou. A computationally assisted cultural heritage conservation method. Journal of Cultural Heritage. 2021; 48 ():119-128.
Chicago/Turabian StyleA. Kioussi; M. Karoglou; E. Protopapadakis; A. Doulamis; E. Ksinopoulou; A. Bakolas; A. Moropoulou. 2021. "A computationally assisted cultural heritage conservation method." Journal of Cultural Heritage 48, no. : 119-128.
High volume fraction carbon nanotube (CNT) composites (7.5–16% vol.) were fabricated by the impregnation of CNT buckypapers into epoxy resin. To enhance the interfacial reaction with the epoxy resin, the CNTs were modified by two different treatments, namely, an epoxidation treatment and a chemical oxidation. The chemical treatment was found to result in CNT length severance and to affect the porosity of the buckypapers, having an important impact on the physico-mechanical properties of the nanocomposites. Overall, the mechanical, electrical, and thermal properties of the impregnated buckypapers were found to be superior of the neat epoxy resin, offering an attractive combination of mechanical, electrical, and thermal properties for multifunctional composites.
George Trakakis; Georgia Tomara; Vitaliy Datsyuk; Labrini Sygellou; Asterios Bakolas; Dimitrios Tasis; John Parthenios; Christoforos Krontiras; Stavroula Georga; Costas Galiotis; Kostas Papagelis. Mechanical, Electrical, and Thermal Properties of Carbon Nanotube Buckypapers/Epoxy Nanocomposites Produced by Oxidized and Epoxidized Nanotubes. Materials 2020, 13, 4308 .
AMA StyleGeorge Trakakis, Georgia Tomara, Vitaliy Datsyuk, Labrini Sygellou, Asterios Bakolas, Dimitrios Tasis, John Parthenios, Christoforos Krontiras, Stavroula Georga, Costas Galiotis, Kostas Papagelis. Mechanical, Electrical, and Thermal Properties of Carbon Nanotube Buckypapers/Epoxy Nanocomposites Produced by Oxidized and Epoxidized Nanotubes. Materials. 2020; 13 (19):4308.
Chicago/Turabian StyleGeorge Trakakis; Georgia Tomara; Vitaliy Datsyuk; Labrini Sygellou; Asterios Bakolas; Dimitrios Tasis; John Parthenios; Christoforos Krontiras; Stavroula Georga; Costas Galiotis; Kostas Papagelis. 2020. "Mechanical, Electrical, and Thermal Properties of Carbon Nanotube Buckypapers/Epoxy Nanocomposites Produced by Oxidized and Epoxidized Nanotubes." Materials 13, no. 19: 4308.
In recent years, the study of high hydraulicity natural hydraulic lime (NHL5) mortars has been in the focus of many researchers, as it is considered a compatible, eco-friendly binding material, which can be used both for the restoration of culturally and historically significant structures, as well as for the construction of contemporary buildings. In the present study, artificial neural networks (ANNs) are used, aiming to simulate and map the development of NHL5 mortars' characteristics, such as compressive strength (CS), ratio of compressive to flexural strength (CS/FL) and consistency (CO), for selected mortar mix parameters, namely the binder to sand ratio (B/S), the water to binder ratio (W/B) and the maximum diameter of the aggregate (MDA) for different mortar specimen ages (AS). To this purpose, databases were developed, integrating experimental data from the international literature. Experimental verification of the developed ANN models revealed satisfactory fitting between theoretical and experimental results. This research highlights the potential of ANNs as a tool which can assist in mortar design and/or optimization, while mapping the development of mortar characteristics can assist in revealing the influence of the different mortar mix parameters on each characteristic. Furthermore, by combining the results of the three developed ANNs (CS, CO, CS/FL) targeted multi-parametric design of mortars can be assisted through a novel approach.
Maria Apostolopoulou; Panagiotis G. Asteris; Danial J. Armaghani; Maria G. Douvika; Paulo Lourenco; Liborio Cavaleri; Asterios Bakolas; Antonia Moropoulou. Mapping and holistic design of natural hydraulic lime mortars. Cement and Concrete Research 2020, 136, 106167 .
AMA StyleMaria Apostolopoulou, Panagiotis G. Asteris, Danial J. Armaghani, Maria G. Douvika, Paulo Lourenco, Liborio Cavaleri, Asterios Bakolas, Antonia Moropoulou. Mapping and holistic design of natural hydraulic lime mortars. Cement and Concrete Research. 2020; 136 ():106167.
Chicago/Turabian StyleMaria Apostolopoulou; Panagiotis G. Asteris; Danial J. Armaghani; Maria G. Douvika; Paulo Lourenco; Liborio Cavaleri; Asterios Bakolas; Antonia Moropoulou. 2020. "Mapping and holistic design of natural hydraulic lime mortars." Cement and Concrete Research 136, no. : 106167.
The multidimensional problems that archaeological sites and cultural heritage assets face demand effective multiple criteria decision-making, regarding risk impact identification and evaluation. There is a great array of risks affecting cultural heritage sites and assets nowadays, including environmental and manmade factors. Risk assessment towards decision-making always considers cultural sites’ and asset’s intrinsic values that determine their cultural significance and thus contribute to conservation planning and management through prioritization of the needs and allocation of the available budget accordingly. Therefore, the aim of this study is to support decision-making for maintenance and conservation interventions in archaeological sites and cultural heritage assets. The paper proposes a risk-based approach utilising the Analytic Network Process (ANP), a multi-criteria decision-making method incorporating both qualitative and quantitative criteria with interdependences and feedback. The proposed approach is tested and validated through an illustrative application regarding a classical monument of an archaeological site of Athens subjected to the conditions of a typical urban environment. The application of this method allows for interdisciplinary, multi-criteria analysis of risk towards interventions decision-making against complex and demanding conservation cases.
Anastasia Kioussi; Konstantinos Kirytopoulos; Maria Karoglou; Asterios Bakolas. A Risk-Based Approach for Assessing Social Sustainability Performance of Cultural Heritage Construction Works. International Journal of Architectural Heritage 2020, 1 -14.
AMA StyleAnastasia Kioussi, Konstantinos Kirytopoulos, Maria Karoglou, Asterios Bakolas. A Risk-Based Approach for Assessing Social Sustainability Performance of Cultural Heritage Construction Works. International Journal of Architectural Heritage. 2020; ():1-14.
Chicago/Turabian StyleAnastasia Kioussi; Konstantinos Kirytopoulos; Maria Karoglou; Asterios Bakolas. 2020. "A Risk-Based Approach for Assessing Social Sustainability Performance of Cultural Heritage Construction Works." International Journal of Architectural Heritage , no. : 1-14.
There is a deep and often impassioned postulation that preservation is virtuous for societal well-being, collective identity and for the environment. This idea is an important paradigm to guide rehabilitation strategies for historic buildings. However, there is a need for data and research in order to validate the contribution of preservation to environmental and cultural sustainability. These research results will support preservation-related decision-making, in which tensions and conflicts with sustainability goals are a routine. Nowadays, there is a strong belief that historic buildings of the 20th century also need to be preserved to create the identities of neighborhoods and cities and suitable strategies need to be applied to extend their lifespan in an environmentally friendly and sustainable way. This research, based on the assumption that integrating sustainability considerations in historic buildings needs a quantifiable approach, selected eight refugee block apartment flats dating back to the interwar period—endowed with architectural, aesthetical and urban history-related values and acknowledged as exceptional examples of Bauhaus architecture in Greece—for an experimental procedure based on life cycle analysis (LCA). Taking into account the deteriorated state of conservation of the buildings, different preservation interventions were analyzed, focusing on the conservation of the initial architectural form of the buildings and critical issues such as the increase in energy efficiency after restoration. The research concludes that this type of assessment can inform urban strategies, making a nexus between preservation and the environmental component of sustainability.
Maria Karoglou; Stella Sofia Kyvelou; Christos Boukouvalas; Chryssa Theofani; Asterios Bakolas; Magdalini Krokida; Antonia Moropoulou. Towards a Preservation–Sustainability Nexus: Applying LCA to Reduce the Environmental Footprint of Modern Built Heritage. Sustainability 2019, 11, 6147 .
AMA StyleMaria Karoglou, Stella Sofia Kyvelou, Christos Boukouvalas, Chryssa Theofani, Asterios Bakolas, Magdalini Krokida, Antonia Moropoulou. Towards a Preservation–Sustainability Nexus: Applying LCA to Reduce the Environmental Footprint of Modern Built Heritage. Sustainability. 2019; 11 (21):6147.
Chicago/Turabian StyleMaria Karoglou; Stella Sofia Kyvelou; Christos Boukouvalas; Chryssa Theofani; Asterios Bakolas; Magdalini Krokida; Antonia Moropoulou. 2019. "Towards a Preservation–Sustainability Nexus: Applying LCA to Reduce the Environmental Footprint of Modern Built Heritage." Sustainability 11, no. 21: 6147.
In recent years, natural hydraulic lime (NHL) mortars have gained increased attention from researchers, not only as restoration materials for monuments and historical buildings, but also as an eco-friendly material which can be used as binder to formulate mortars for contemporary structures. In the present study, an extended database related to NHL mortars is compiled, related to all three NHL grades (NHL5, NHL3.5, NHL2) and soft computing techniques namely artificial neural networks (ANN) are utilized to reveal the influence of the mortar’s mix design on mechanical strength, as well as to predict the compressive strength of NHL mortar mixes. Influence of the binder to aggregate, water to binder and maximum aggregate size on the compressive strength of a mortar at different mortar ages is revealed, for the three grades of natural hydraulic lime, further highlighting aspects of this “new” material, which has been used as a binder since antiquity.
Maria Apostolopoulou; Danial J. Armaghani; Asterios Bakolas; Maria G. Douvika; Antonia Moropoulou; Panagiotis G. Asteris. Compressive strength of natural hydraulic lime mortars using soft computing techniques. Procedia Structural Integrity 2019, 17, 914 -923.
AMA StyleMaria Apostolopoulou, Danial J. Armaghani, Asterios Bakolas, Maria G. Douvika, Antonia Moropoulou, Panagiotis G. Asteris. Compressive strength of natural hydraulic lime mortars using soft computing techniques. Procedia Structural Integrity. 2019; 17 ():914-923.
Chicago/Turabian StyleMaria Apostolopoulou; Danial J. Armaghani; Asterios Bakolas; Maria G. Douvika; Antonia Moropoulou; Panagiotis G. Asteris. 2019. "Compressive strength of natural hydraulic lime mortars using soft computing techniques." Procedia Structural Integrity 17, no. : 914-923.
The aim of this work is to study the influence of calcium hydrated lime (lime putty or hydrated lime powder) to the chemical and physico-mechanical characteristics of lime mortars. The mortars were designed with the same mixing ratio of lime/aggregates and evaluated till 18 months of curing. The carbonation rate is evaluated via DTA/TG, the pore structure by mercury intrusion porosimetry and the hygric properties via capillary rise and water immersion tests. Mortars’ shrinkage and apparent density were also measured along with mechanical strength and static and dynamic modulus of elasticity that were evaluated by using conventional mechanical tests and ultrasonic technique. The obtained results revealed that lime powder mortars present a higher carbonation rate and higher values of compressive strength compared to lime putty mortars. Lime powder mortars also exhibit a unimodal pore size distribution (while lime putty mortars present a bimodal one) and higher capillary rise coefficient and porosity accessible to water in respect to lime putty mortars.
Eleni Aggelakopoulou; Asterios Bakolas; Antonia Moropoulou. Lime putty versus hydrated lime powder: Physicochemical and mechanical characteristics of lime based mortars. Construction and Building Materials 2019, 225, 633 -641.
AMA StyleEleni Aggelakopoulou, Asterios Bakolas, Antonia Moropoulou. Lime putty versus hydrated lime powder: Physicochemical and mechanical characteristics of lime based mortars. Construction and Building Materials. 2019; 225 ():633-641.
Chicago/Turabian StyleEleni Aggelakopoulou; Asterios Bakolas; Antonia Moropoulou. 2019. "Lime putty versus hydrated lime powder: Physicochemical and mechanical characteristics of lime based mortars." Construction and Building Materials 225, no. : 633-641.
The sustainable preservation of monuments requires the use of performing materials which are at the same time compatible with the monument’s historical building materials to ensure structural integrity, adequate performance of the structure in earthquake stresses, and resilience of both restoration and historical materials. This is especially true for cultural heritage assets that have experienced major destruction, demanding extensive reconstruction. The Plaka Bridge in Epirus, Greece, partially collapsed after a heavy rainfall in 2015. It was a supreme example of traditional stone bridge architecture of the region and an important landmark. In the present study, a potential restoration stone from a nearby quarry was examined in terms of compatibility in relation to the dominant historical building stone of the bridge, as well as in terms of mechanical performance, through a variety of in lab techniques. In addition, criteria were set for restoration mortars, taking into account the characteristics of the historical materials, as well as the environment of the bridge. The results of the study regarding the restoration stone and mortars are presented and assessed, in order to select the most appropriate restoration materials for Plaka Bridge in its upcoming restoration, aiming to enhance the overall resilience of the structure.
Maria Apostolopoulou; Ioannis Nikolaidis; Iakovos Grillakis; Myrto Kalofonou; Vasileios Keramidas; Ekaterini T. Delegou; Maria Karoglou; Asterios Bakolas; Kyriakos C. Lampropoulos; Charalampos Mouzakis; Antonia Moropoulou. The Plaka Bridge in Epirus: An Evaluation of New Building Materials for Its Restoration. Heritage 2019, 2, 1136 -1159.
AMA StyleMaria Apostolopoulou, Ioannis Nikolaidis, Iakovos Grillakis, Myrto Kalofonou, Vasileios Keramidas, Ekaterini T. Delegou, Maria Karoglou, Asterios Bakolas, Kyriakos C. Lampropoulos, Charalampos Mouzakis, Antonia Moropoulou. The Plaka Bridge in Epirus: An Evaluation of New Building Materials for Its Restoration. Heritage. 2019; 2 (2):1136-1159.
Chicago/Turabian StyleMaria Apostolopoulou; Ioannis Nikolaidis; Iakovos Grillakis; Myrto Kalofonou; Vasileios Keramidas; Ekaterini T. Delegou; Maria Karoglou; Asterios Bakolas; Kyriakos C. Lampropoulos; Charalampos Mouzakis; Antonia Moropoulou. 2019. "The Plaka Bridge in Epirus: An Evaluation of New Building Materials for Its Restoration." Heritage 2, no. 2: 1136-1159.
The Temple of Apollo Pythios, built in the Hellenistic era (3rd–1st century BC), is located in the ancient Acropolis of Rhodes. It was excavated during the Italian occupation and reconstructed by the Italians in the period 1937–8. The method of the “scenographic” restoration was the “mixed structure” technique using a core of reinforced concrete in combination with new biocalcarenite stones and the integration of very few ancient architectural members. Its proximity to the sea and the corresponding salt decay phenomena, aggravated by the erroneous reconstruction methodology and materials, have further deteriorated its state of preservation. Today, the four columns, epistyle and entablature of the Italian interventions demand immediate restoration actions to ensure the monument’s sustainability. This can only be achieved through a combined study of the performance of potential restoration materials and assessment of their compatibility with the historical materials. In the present study, the characteristics of the Temple’s historical porous stones are presented along with the characteristics of five quarry stones, aiming to evaluate which quarry stone is the most appropriate for use in the upcoming restoration. Restoration mortars are designed and evaluated in respect to both the historical materials and the quarry stones, aiming to select the optimum restoration mortar, which can achieve the required level of performance and compatibility and ensure sustainability of the structure as a whole.
Maria Apostolopoulou; Vasileios Keramidas; Niki Galanaki; Myrto Kalofonou; Chariklia Skoula; Maria Karoglou; Ekaterini T. Delegou; Charalampos Mouzakis; Asterios Bakolas; Antonia Moropoulou; Maria Pikoula; Anna Kalagri; Eleni Farmakidou; Maria Michailidou. A Study on the Historical Materials of the Apollo Pythios Temple in Rhodes and the Evaluation of Potential Restoration Materials. Heritage 2019, 2, 988 -1022.
AMA StyleMaria Apostolopoulou, Vasileios Keramidas, Niki Galanaki, Myrto Kalofonou, Chariklia Skoula, Maria Karoglou, Ekaterini T. Delegou, Charalampos Mouzakis, Asterios Bakolas, Antonia Moropoulou, Maria Pikoula, Anna Kalagri, Eleni Farmakidou, Maria Michailidou. A Study on the Historical Materials of the Apollo Pythios Temple in Rhodes and the Evaluation of Potential Restoration Materials. Heritage. 2019; 2 (1):988-1022.
Chicago/Turabian StyleMaria Apostolopoulou; Vasileios Keramidas; Niki Galanaki; Myrto Kalofonou; Chariklia Skoula; Maria Karoglou; Ekaterini T. Delegou; Charalampos Mouzakis; Asterios Bakolas; Antonia Moropoulou; Maria Pikoula; Anna Kalagri; Eleni Farmakidou; Maria Michailidou. 2019. "A Study on the Historical Materials of the Apollo Pythios Temple in Rhodes and the Evaluation of Potential Restoration Materials." Heritage 2, no. 1: 988-1022.
One of the main issues in the field of Monument Protection is the degradation of limestones as a result of the action of various weathering mechanisms. The modification of widely used silicon-based materials for stone consolidation is intended to overcome the well-known drawbacks of these materials, such as shrinkage and cracking tendency during drying. The addition of nano-dispersions into a silica matrix aims to enhance their effectiveness in several ways, by improving their properties and their viscoelastic behavior. The objective of the current research was the application and evaluation of Si-based modified nanocomposites of optimized composition. The materials were applied to two types of porous stone and the assessment of their compatibility and performance was carried out by using both laboratory techniques and methods (SEM, MIP, TMA, Water Absorption by Capillarity, determination of Water Vapor Permeability) and non-destructive techniques (Ultrasound Velocity determination, Colorimetry). To study the resistance of the treated samples to soluble salt crystallization, accelerated aging tests were performed in sodium sulfate cycles. The modified consolidants consist of an ethyl silicate matrix reinforced with colloidal silica (SiO2) nano-particles and titania (TiO2) particles. Based on the results, the consolidating material does not significantly alter the characteristics of the microstructure and the appearance of stones, allowing the passage of water vapor, while increasing their mechanical properties. Furthermore, the accelerated ageing tests revealed that the treated samples have a higher resistance to the action and crystallization of soluble salts in comparison to untreated.
E. Ksinopoulou; A. Bakolas; A. Moropoulou. Consolidation effectiveness of modified Si-based nanocomposites applied to limestones. Materials and Structures 2018, 51, 156 .
AMA StyleE. Ksinopoulou, A. Bakolas, A. Moropoulou. Consolidation effectiveness of modified Si-based nanocomposites applied to limestones. Materials and Structures. 2018; 51 (6):156.
Chicago/Turabian StyleE. Ksinopoulou; A. Bakolas; A. Moropoulou. 2018. "Consolidation effectiveness of modified Si-based nanocomposites applied to limestones." Materials and Structures 51, no. 6: 156.
The aim of this research is to design and produce concrete for the restoration of Byzantine monuments. Mixes with different binders, pozzolanic additions and aggregates were produced. The chemical (hydraulic products, consumption of Ca[OH]2), the physical characteristics (apparent density, porosity accessible to water through capillaries and capillary rise coefficient), the compressive and flexural strength, the static and dynamic modulus of elasticity were evaluated. From the obtained results, it is drawn that a light-weight concrete with low value of elasticity modulus was produced by mixing hydrated lime, artificial pozzolan (2.5% p.w.), ceramic fragments and sand. The chemical and the physico-mechanical characteristics of this concrete fit with the ones of the authentic concrete, ensuring the compatibility to building materials.
Eleni Aggelakopoulou; Asterios Bakolas; Antonia Moropoulou. Design and evaluation of concrete for restoration interventions on Byzantine monuments. Journal of Cultural Heritage 2018, 34, 166 -171.
AMA StyleEleni Aggelakopoulou, Asterios Bakolas, Antonia Moropoulou. Design and evaluation of concrete for restoration interventions on Byzantine monuments. Journal of Cultural Heritage. 2018; 34 ():166-171.
Chicago/Turabian StyleEleni Aggelakopoulou; Asterios Bakolas; Antonia Moropoulou. 2018. "Design and evaluation of concrete for restoration interventions on Byzantine monuments." Journal of Cultural Heritage 34, no. : 166-171.
In order to evaluate the pozzolanic activity of a natural pozzolan (NP) of rhyolitic composition, several pastes were prepared by mixing the pozzolan with hydrated lime, in different ratios. The pastes were stored in standard conditions (RH = 99 ± 1%, T = 25 ± 1 °C) and evaluated using thermal analysis (TG-DTA), X-ray diffraction, compressive strength tests and mercury intrusion porosimetry, up to 270 days of curing. The obtained results showed that the compounds formed are CSH and C4ACH11 (monocarboaluminate). The calcium hydroxide consumption increases as the initial amount of the natural pozzolan in the paste augments. As the NP/lime ratio increases, the open total porosity and total cumulative volume decrease, while the bulk density increases. The maximum strength development is obtained for NP/lime ratio of 2.
Asterios Bakolas; Eleni Aggelakopoulou. Pozzolanic activity of natural pozzolan–lime pastes and physicomechanical characteristics. Journal of Thermal Analysis and Calorimetry 2018, 135, 2953 -2961.
AMA StyleAsterios Bakolas, Eleni Aggelakopoulou. Pozzolanic activity of natural pozzolan–lime pastes and physicomechanical characteristics. Journal of Thermal Analysis and Calorimetry. 2018; 135 (6):2953-2961.
Chicago/Turabian StyleAsterios Bakolas; Eleni Aggelakopoulou. 2018. "Pozzolanic activity of natural pozzolan–lime pastes and physicomechanical characteristics." Journal of Thermal Analysis and Calorimetry 135, no. 6: 2953-2961.
The rehabilitation of the Holy Aedicule of the Holy Sepulchre in Jerusalem, completed in March 2017, aimed to address the deformation problems encountered after its most recent reconstruction in 1810. A diagnostic study performed by the National Technical University of Athens (NTUA), indicated the cause of the deformations and revealed the Aedicule’s structural layers. The results permitted the design, selection and application of compatible and performing restoration mortars, while the assessment of their application was achieved through a multispectral approach and in combination with an integrated analysis throughout the rehabilitation project. The results acquired through analytical and non destructive techniques show that compatibility was ensured and the structure was adequately strengthened and concludes in a methodological approach regarding all stages of a rehabilitation project of a complex multilayered monument.
Maria Apostolopoulou; Ekaterini Delegou; Emm. Alexakis; M. Kalofonou; Kyriakos Lampropoulos; E. Aggelakopoulou; A. Bakolas; A. Moropoulou. Study of the historical mortars of the Holy Aedicule as a basis for the design, application and assessment of repair mortars: A multispectral approach applied on the Holy Aedicule. Construction and Building Materials 2018, 181, 618 -637.
AMA StyleMaria Apostolopoulou, Ekaterini Delegou, Emm. Alexakis, M. Kalofonou, Kyriakos Lampropoulos, E. Aggelakopoulou, A. Bakolas, A. Moropoulou. Study of the historical mortars of the Holy Aedicule as a basis for the design, application and assessment of repair mortars: A multispectral approach applied on the Holy Aedicule. Construction and Building Materials. 2018; 181 ():618-637.
Chicago/Turabian StyleMaria Apostolopoulou; Ekaterini Delegou; Emm. Alexakis; M. Kalofonou; Kyriakos Lampropoulos; E. Aggelakopoulou; A. Bakolas; A. Moropoulou. 2018. "Study of the historical mortars of the Holy Aedicule as a basis for the design, application and assessment of repair mortars: A multispectral approach applied on the Holy Aedicule." Construction and Building Materials 181, no. : 618-637.
Water capillary absorption is one of the main water uptake mechanisms in building materials, affecting their overall durability. Thus, the investigation of their capillary rise kinetics can be very useful as regards understanding buildings behavior, contributing to the increase of their durability and their service life. For this reason, a first-order mathematical model was used describing the capillary water uptake under dynamic environmental conditions (different air velocity, air temperature, and relative air humidity) for various natural and artificial building materials. This model successfully fits the experimental data. From the results, it was found that both building materials’ intrinsic characteristics and environmental conditions influence the capillary rise kinetics. In order to assess the validity of the proposed model, a comparison with a similar model was performed. The fitting of the utilized model was more accurate because of the incorporation of the environmental parameters into it. Finally, the proposed model was utilized in order to predict the capillary water uptake under hypothetical extreme weather real-case scenarios. It was found that the proposed model can successfully predict the capillary water uptake under different real-case environmental conditions. The applicability of this semi-empirical model, using parameters with physical meaning, could make it suitable for use in building simulators. This model can contribute to risk assessment tools, dealing with various challenges related to climate change and its effect upon built environment.
Nikos Karagiannis; Maria Karoglou; Asterios Bakolas; Magdalini Krokida; Antonia Moropoulou. The influence of dynamic environmental conditions on capillary water uptake of building materials. Journal of Building Physics 2018, 42, 506 -526.
AMA StyleNikos Karagiannis, Maria Karoglou, Asterios Bakolas, Magdalini Krokida, Antonia Moropoulou. The influence of dynamic environmental conditions on capillary water uptake of building materials. Journal of Building Physics. 2018; 42 (4):506-526.
Chicago/Turabian StyleNikos Karagiannis; Maria Karoglou; Asterios Bakolas; Magdalini Krokida; Antonia Moropoulou. 2018. "The influence of dynamic environmental conditions on capillary water uptake of building materials." Journal of Building Physics 42, no. 4: 506-526.
Incompatible restoration mortars used extensively in recent years have inferred irreversible damage to the original building stones of masonries. Recent research has led to the development of compatibility criteria for the restoration mortars in relation to historical materials, through the reverse engineering approach. In the restoration of historical stone masonries, apart from the issue of compatibility which is mainly of a physicochemical nature linked to ensuring breathability and avoiding preferential percolation of salt solutions to the original building stones, the issue of restoration mortars’ mechanical performance is of equal importance to achieve sustainability. An integrated methodological approach is presented aiming to the selection of the optimum compatible and performing restoration mortar for conservation/restoration interventions. The Kaisariani Monastery and the bridge of Plaka in Greece, as well as the Holy Aedicule in Jerusalem, serve as case studies in order to illustrate the methodological approach.
M. Apostolopoulou; E. Aggelakopoulou; A. Bakolas; A. Moropoulou. Compatible Mortars for the Sustainable Conservation of Stone in Masonries. Advanced Materials for the Conservation of Stone 2018, 97 -123.
AMA StyleM. Apostolopoulou, E. Aggelakopoulou, A. Bakolas, A. Moropoulou. Compatible Mortars for the Sustainable Conservation of Stone in Masonries. Advanced Materials for the Conservation of Stone. 2018; ():97-123.
Chicago/Turabian StyleM. Apostolopoulou; E. Aggelakopoulou; A. Bakolas; A. Moropoulou. 2018. "Compatible Mortars for the Sustainable Conservation of Stone in Masonries." Advanced Materials for the Conservation of Stone , no. : 97-123.
Maria Apostolopoulou; Elissavet Drakopoulou; Maria Karoglou; Asterios Bakolas. Methods of Consolidation and Protection of Pentelic Marble. ASMOSIA XI, Interdisciplinary Studies on Ancient Stone, Proceedings of the XI International Conference of ASMOSIA 2018, 749 -759.
AMA StyleMaria Apostolopoulou, Elissavet Drakopoulou, Maria Karoglou, Asterios Bakolas. Methods of Consolidation and Protection of Pentelic Marble. ASMOSIA XI, Interdisciplinary Studies on Ancient Stone, Proceedings of the XI International Conference of ASMOSIA. 2018; ():749-759.
Chicago/Turabian StyleMaria Apostolopoulou; Elissavet Drakopoulou; Maria Karoglou; Asterios Bakolas. 2018. "Methods of Consolidation and Protection of Pentelic Marble." ASMOSIA XI, Interdisciplinary Studies on Ancient Stone, Proceedings of the XI International Conference of ASMOSIA , no. : 749-759.