Plaster Layer Research Articles

Hubert Goltzius’s Lebendige Bilder Gar Nach Aller Keysern, Emperor Maximilian II, and Renaissance Cycles of Fresco Portraits of Emperors in Palaces in Silesia

At the beginning of the 21st century, there were sensational discoveries in two palaces located in Ciechanowice and Struga in Silesia (Poland). During their renovations, Renaissance fresco cycles of portraits of emperors from the Roman, medieval, and early modern times appeared under the layer of plaster in the representative dining rooms (27 in the palace in Struga and about 50 in the palace in Ciechanowice). They were painted in the 1580s (in Ciechanowice, the date is 1588) by the same unknown artist. This article is the first to attempt to establish the most important facts related to the creation of both fresco cycles. The frescoes were founded by representatives of influential Silesian Protestant nobility: Heinrich von Reichenbach (Ciechanowice) and Abraham von Czettritz und Neuhaus (Struga). Both nobles attended the funeral of Emperor Maximilian II, which took place in Prague in 1577. This is where they purchased a work by the Dutch printmaker, painter, and numismatist, Hubert Goltzius, Lebendige Bilder Gar Nach Aller Keysern […] (published in Antwerp in 1557), whose specially prepared copy had been solemnly presented to Emperor Maximilian II in 1562. The book contains 133 monochrome woodcut illustrations with portraits of emperors in circular frames by the Dutch artist Joss van Gietleughen, which—together with accompanying inscriptions—were used as models for fresco paintings in both Silesian palaces. The foundation of the cycles of portraits of the emperors of the Roman Empire and the Holy Roman Empire of the German Nation in the representative halls of the palaces in Ciechanowice and Struda, which ended with a joint representation of Emperor Maximilian II and the King of Spain, Philip II Habsburg, was a way to show the gratitude of both prominent and wealthy Protestant nobles towards Emperor Maximilian II. During his reign, imperial power was the source and guarantee of religious freedoms for Protestants in Silesia. It is significant that both cycles left out the person of emperor regnant, Rudolf II, who soon after assuming the imperial throne abandoned his father’s tolerant policy towards Protestants. Although the author of both series of frescoes was probably a local painter, they are a unique artistic realization not only in Silesia but also in the whole of Central Europe, and they can only be compared to the popular Renaissance portrait galleries of “famous men” (uomini famosi).

Application of the FDTD Method for Multivariate Analysis of the Influence of Conductivity and the Arrangement of Hollows Inside Bricks on the Values of Electric Field Intensity

The article contains a numerical analysis of the effects of electromagnetic wave propagation in an area containing a non-ideal, non-uniform, and absorbing dielectric. The analysis concerned the influence of the structure of the building material and its electrical parameters on the electric field intensity. The analysis took into account the variability of the number of hollows in the brick, the width of hollows, as well as the arrangement of these hollows relative to each other using the example of two types of bricks. The article also provides the most commonly used values of electrical parameters for building materials (brick, plaster). For this reason, the article includes results for different values of conductivity (0–0.2 S/m). The FDTD (Finite Difference Time Domain) method was used for multivariate analysis. The aim was to verify the correctness of the numerical assumptions adopted. Using the example of the most commonly used wall structure in construction, the results obtained using the FDTD method were compared with values obtained using another numerical method, the finite element method (FEM). The influence of an additional layer of plaster on the considered wall on the electric field was also checked. The analysis showed that a symmetrical arrangement of bricks results in higher values of the electric field by an average of 20%. Of course, this depends on the length of the hollows and the number of holes. The highest field values occur at low conductivities (0–0.04 S/m). A brick wall with a larger number of hollows and a symmetrical brick arrangement shows the highest electric field intensity, especially for hollow sizes (0.009–0.015 m).

Justification of the Efficiency of Application of Plaster for Fire Protection of Concrete Structures

The problem of using concrete for building structures is to ensure their stability and durability during operation within wide limits. Therefore, the object of research was the change in the properties of concrete during a fire and its protection when applying a heat-insulating layer of plaster, which is able to inhibit the temperature when the flame affects the coating. It has been proven that in the process of thermal action on fire-resistant plaster, the process of thermal insulation of concrete consists in the application of materials with low thermal conductivity as part of the plaster on the surface of the material. Similarly, under the influence of the burner flame, a temperature was created on the surface of the sample under the influence of the burner flame with a temperature of more than 800°С for 1800 s, the temperature on the surface of the concrete under the plaster coating did not exceed 120°С, which indicates the formation of a curtain for temperature. In this regard, experimental studies were conducted and it was established that the presence of aluminosilicate microspheres in the plaster leads to the formation of a thermally protective layer on the surface of concrete resistant to mechanical vibrations. According to experimental data, the coefficient of thermal conductivity and thermal conductivity of the plaster was calculated, which is 6.22·10–7 m2/s and 0.142 W/(m∙K), respectively, due to the addition of aluminosilicate microspheres. Thus, there are reasons to assert the possibility of targeted regulation of concrete fire protection processes by using fire-resistant plaster capable of forming a protective layer on the surface of the material, which slows down the rate of heat transfer.

Preparation and Characterization of Anti-Microbial Wound Healing Materials from Natural Origins

Abstract Many types of polymers utilized as wound dressings, Polycaprolactone (PCL) displays high degree of biocompatibility as well as biodegradability, the mechanical strength states PCL in the foreground materials used in wound healing therapies. Current work aims to develop new types of wound plaster dressing, a multiple of natural and medical materials (aloe Vera, calendula and phenobarbital) were used to enhance the anti-microbial behavior as well as pain removal during wound healing period. Aloe Vera gels, Calendula extraction, with phenobarbital drug were precipitates on PCL layer in different percentage. Microstructure observation proves that polycaprolactone polymer is good base material supports dressing constituents, wound dressing homogeneity increased due to chemical reactions between the Aloe Vera and other materials. the main elements of dressing (carbon and oxygen) observed from chemical analysis (EDS) which is also showed that using combination of natural plants (aloe vera and Calendula) with phenobarbital medicine create wound plaster layer with wide range of active elements lead to therapeutic effects including antibacterial, In (FTIR) the results show using mixture of natural additives (aloe, calendula), medicine like phenobarbital in PCL lead to create wound plaster with high (OH) content acts to expedite the skin’s healing process by maintaining the natural level of minerals and hydration at wound area. Hydrophobicity of wound can minimized when adding some hydrophilic materials like Aloe Vera, phenobarbital and calendula, Aloe Vera gel, phenobarbital, as well as calendula decrease the contact angle value. Providing high adhesion between wound plaster and skin tissue. All prepared wound plaster has same and high resistance to Staphylococcus bacteria (40mm).

ADHESIVE ABILITY OF GYPSUM-CONTAINING PLASTER COMPOSITIONS

The traditional material for the construction of buildings in the Northern Black Sea region is a cheap local stone ‒ limestone-shell rock. Most of the buildings in the central part of the city of Odesa, which are of historical and architectural value, are constructed of this material. With proper care and maintenance, these structures can perform their functions for hundreds of years, but as a result of shell rock moisture due to negligent operation and a number of other reasons, the supporting structures are damaged, followed by the collapse of the building. In many cases, the direct cause of the destruction of load-bearing walls is the damage or absence of the outer plaster layer. Repairing walls with cement compounds exacerbates the problem. The article discusses some aspects of the possible use of gypsum-based composite materials for repairing damaged walls of limestone-shell rock buildings. The requirements for the repair composition are formulated. The expediency of using gypsum as a binder for the repair plaster mixture for exterior repairs is substantiated. An ash-gypsum-cement composition was used to increase the water resistance of the plaster. Sufficient water resistance and vapor permeability of the proposed composition were confirmed. This paper presents the results of studying the adhesive strength of the contact of the developed composition with the surface of various materials. Methods and measuring equipment developed at the ODABA were used. The adhesion strength of the proposed mixture with the surface of shell rock is close to the standard strength. The use of the adhesive additive Ceresit CC 81 increases the adhesive strength of the joint of the proposed composition with shell rock by 1.5 ‒ 2 times. The optimal amount of the adhesive additive to be introduced will be determined by the results of a multifactorial experiment to study the effect of a complex of chemical additives of different functional purposes on the properties of the proposed repair composition.

Deep learning for the detection and classification of adhesion defects in antique plaster layers

This paper aims is to show an automated intelligent measurement system for the detection of adhesion defects between architectural antique plaster layers. The method emulates the traditional conservators’ procedure based on acoustical perturbations, auscultation, detection and classification. The system makes use of a hardware device, known in literature as PICUS, for the generation and acquisition of acoustic signals, while the processing of the acquired signals is handled by a deep learning (DL) architecture designed ad hoc. After a brief description of the PICUS system and the acoustic data acquisition procedure, the whole architecture of the DL system is carefully described. The proposed method has been validated by a significant case study. The system shows an accuracy of up to 82% (± 2%) in multi-class classification and up to 99% (± 1%) in binary classification. In particular, the obtained results suggest a satisfactory precision in the detection of areas where stabilization is necessary.

Research on new technology of resource-saving ultra-thin stone curtain wall

Ultra thin stone curtain wall technology is a resource-saving innovation. This article explores the application of ultra-thin stone in building exterior wall decoration, including pasted curtain walls, self insulated walls, AAC walls, and decorative insulation composite board exterior wall insulation systems. This technology has advantages such as thin thickness, light weight, low cost, convenient construction, and excellent self insulation performance. The key construction points include waterproofing, rust prevention treatment, use of high standard adhesives, embedding of steel wire mesh in the plaster layer, and small mortar joint technology. The future development direction should focus on innovation in the production technology of ultra-thin stone panels and new directions for stone products.

Using the methyl cellulose poultice method to remove plaster and burlap - A case study on Triceratops bone

The dinosaur collection at the Natural History Museum, London (NHM) includes a Triceratops skull (NHMUK PV R 3886), purchased from Charles Sternberg in 1909. While most of the skull is on public display in the Dinosaurs gallery, two large sections of the frill (the squamosal bones) had been replicated for the display and the originals left in storage. With much of the fossil bone obscured by plaster of Paris, the original frill sections were deemed of limited use to science in their current form. A work request was received to strip away as much artificial material as possible to determine the extent of the original fossil material. An air scribe fitted with a chisel stylus proved initially effective, but soon revealed an additional obstacle – layers of hessian underneath. The methyl cellulose poultice method was used to swell the hessian, aiding softening of the plaster, and allowing layers to be torn off in strips. The fine layer of plaster remaining on the bone was removed, where possible, with a Split-V ultrasonic tool. This sequence of treatments can be utilised at minimal risk to specimens in similar situations when a hessian and plaster jacket has been applied but a separator layer has been omitted.

Degradation Mechanisms of Mortar and Plaster Layers.

This article presents a case of complex investigation of defects of lime mortar and plaster that have been developing over a period of 48 years in a house in Prague and are strongly influenced by thermal and salt crystallization cycles. The aim of this research was to describe the degradation phenomena of mortars and plasters observed on a narrowly limited part of the building, combining structural elements of different types and ages and to explain the mechanisms of their formation and development. The geometric characteristics of the defects were determined by non-destructive methods, especially optical interference moiré, laser profilometry, photogrammetry, and infrared thermography. Material data were determined on samples by electron microscopy, ion exchange chromatography, and direct moisture content measurements. The results supported the hypothesis of the increase in the deformation of large buckles of detached plasters by the mechanism of buckling caused by loading of the edges with compression generated by volume changes. Direct loading of the boundary surfaces causes the formation of bulges in the confined areas. This study shows the importance of failure analysis of real structures to gain knowledge about the behavior of structures and materials under long-term service conditions.

Ensuring fire safety: compliance tests for the use of polystyrene foam in facades systems

Ensuring fire safety is the most important thing in the construction industry, especially when it comes to facade materials. The inherent flammability of polystyrene foam poses significant safety concerns, especially when integrated into facade systems. Therefore, the main focus is on meeting the strict flammability requirements set for construction products, which are assessed by applying rigorous test procedures. This study focuses on the fire resistance testing of a facade system using EPS 70 with graphite additives. The system has been evaluated according to the strict DIN 4102-20 standards. Tests were conducted under real-world conditions to gain insight into the performance of the EPS 70 in real-world fire scenarios. Temperature measurements were taken at various points in the facade system, including at least 3.5 meters above the combustion chamber. The results showed that the temperature does not exceed 500 °C, so it is possible to quantify the thermal properties of the material and the ability to prevent the vertical spread of fire. After the tests, detailed post-test inspections were carried out to evaluate the internal flame propagation after removing the top layer of plaster. The study confirms that polystyrene foam EPS 70 with graphite additives meets the fire safety requirements of DIN 4102-20, which suggests that it can be used more widely in building facades to improve fire safety in residential and commercial buildings. The study highlights the importance of adhering to installation standards, emphasizing the need for accurate installation practices. It also encourages the development of new composite materials with similar or improved fire safety properties, laying the foundation for further innovations in fire-resistant materials

Numerical Study of the Thermal Behavior of a Wall Containing Phase Change Material (PCM) in a Hot and Dry Climate

Current buildings in Burkina Faso, particularly in the Sahelian zone, built with local materials are energy-intensive and sources of discomfort for the occupants. However, the role of housing is to provide man with shelter which protects him from external climatic conditions and offers him thermal comfort. In this work, we present a numerical study of the thermal behavior of a wall containing a phase change material (PCM) in the Sahelian zone. The MCP used in this study is RT27 paraffin with a melting temperature of 27°C and a latent heat of fusion of 179kJ/kg. The equations obtained were adimensionalized and discredited by the finite element method and solved using COMSOL Multiphysics software version 5.3. To this end, we were interested on the one hand in the study of the evolution of the flow of heat and the temperature at the level of the external and internal walls of the wall. On the other hand, we studied the effect of the location of a layer of PCM mortar, simple plaster or cement plaster on the temperature of the internal wall of the wall. The results show the magnitude of heat flux and temperature is greatly reduced by the incorporation of PCM into the wall.

The Use of Phase Change Materials to Improve the External Walls' Thermal Parameters of Heated Buildings

Currently, it is estimated that the construction sector consumes over 40% of the energy produced and about 50% of the mass of processed materials. As a consequence, there is a challenge to look for alternative material solutions allowing for the storage and conversion of energy. Phase change materials give us such opportunities. Their introduction leads to additional benefits related to thermal parameters. The work presents a short overview of PCMs along with the possibility of their application. Then, as part of the research, the selected phase change material was applied to the internal plaster layer of an external wall to check its activity. The obtained results were compared to the values of reference samples (without PCM). The proposed solution leads to the improvement of the analyzed partitions' thermal parameters.

ВЛИЯНИЕ НА КАЧЕСТВО ПРОИЗВОДСТВА ШТУКАТУРНЫХ РАБОТ ПАРАМЕТРОВ РОБОТА-ШТУКАТУРА

The article considers the main aspects of studying the effective use of plastering machines and mixtures in construction through the use of automated and mechanized systems, units and robots. Theoretical aspect of the study of the process of plaster layer compaction with the help of a vibration platform of a robot plasterer with adjustable parameters. The main design and technological parameters of vibration compaction of the plaster layer and their influence on the efficiency of the process of compaction of vertical walls are revealed. The methods of experimental research are described, as well as experimental installations on which the laboratory experiment was carried out. The use of this technology allows to solve the problem of time costs and increase labor productivity indicators, as well as aspects of economic nature. When changing the physical and mechanical characteristics of the vibration platform its dependence of variation factors allows to form the most favorable conditions for the mechanical effect of vibrations on the efficiency of the process of plastering vertical walls. Plastering mixtures for obtaining a plaster layer are studied, the main physical and mechanical characteristics are analyzed, the requirements to be taken into account in the process of plastering are analyzed. The paper presents a comparison of physical and mechanical characteristics of the vibration platform, reveals the advantages and disadvantages of using different combinations of parameters. It is established that the use of a certain combination or change of one important parameter contributes to the increase of physical and mechanical characteristics in comparison with the traditional method of mechanical action.

Development of lime injection grouts for the stabilisation of detached lime plasters with wall paintings in the unique Romanesque round church in Slovenia

This paper presents the design of lime grouts to stabilise wall paintings from the 13th and 14th centuries in the Romanesque church of St. Nicholas in Selo, Slovenia. Most of the paintings were executed using the secco technique on a single layer of lime plaster made of slaked lime and quartz sand, which was applied to a clay brick masonry base. The thickness of the detached pockets was generally 2 mm to 1 cm, in a few places up to 5 cm, especially in the vault area. Consolidation of detached plaster layers is an irreversible treatment to restore the adhesion between the detached plaster layers. It was therefore important that the grouts met certain criteria in terms of composition and properties in the fresh and hardened state. We developed three grouts that meet general criteria and two specific key requirements, such as low density and sufficient injectability without pre-wetting to prevent new damage and/or the plaster falling off the wall or ceiling during or after the consolidation treatment. The grouts consist of hydrated lime, fillers, polycarboxylate ether superplasticizer (PCE) and water. During the design process, various quartz fillers were tested in different proportions. The reduced density of the grout was achieved by using expanded glass granules as a partial filler substitute. The appropriate injectability of the grout was achieved through the combination of reduced water content and superplasticizer PCE.

The influence of the dowel mounting scheme in facade systems on the thermal protection properties of the enclosing structure

The use of hinged facade systems is a common solution that allows, with the right approach, to effectively solve a wide range of tasks: from issues of thermal protection of buildings and structures to the possibility of giving the building a unique architectural and artistic expression. Such facade systems are multilayer structures, which contain thermal engineering heterogeneities that affect the thermal protection properties of the enclosing structure as a whole. The purpose of the study presented in the proposed article is to study the effect of the dowel fastening scheme in facade systems on the thermal protection properties of the enclosing structure. The facade dowels in the considered enclosing structure will be point thermal inhomogeneities. The object of the study is a hinged facade system with a thin plaster layer. As part of the study, various schemes of fastening thermal insulation boards with facade dowels are considered. The efficiency of using facade dowels, the material of the spacer element of which are innovative materials with a low coefficient of thermal conductivity, is shown.

Photogrammetry for the analysis of plaster technology and ancient painting techniques: A case study on painted plasters from Amarna, Egypt

This paper explores the potential of photogrammetry for the analysis of painted plaster from Amarna, Egypt. The proposed method is applied to two different forms of painted plaster – gypsum floor plaster, and gypsum and mud wall plaster from Amarna in Egypt. The method proposes that the 3D documentation of painted plasters can be used as a non-invasive analytical tool, specifically for studying the stratigraphic structure of plaster layers. Furthermore, the presence of al secco painting techniques is clearly identified, suggesting this method can be implemented for non-destructive analyses and identification of al secco and al fresco painting techniques on plaster, prior to further, more invasive analyses.

X-ray-based examination of artworks by Cy Twombly: art technology and condition of the ‘Original Sculptures’

What are Cy Twombly’s sculptures made of? This article presents an overview of a non-destructive examination conducted on three sculptures by American artist Cy Twombly (1928–2011) as part of an art-technological research project at the Doerner Institut in Munich. The artworks are part of the collection of the Brandhorst Museum and belong to Twombly’s series of so-called ‘Original Sculptures’: assemblages of individual found objects, which the artist covered and modified with layers of plaster and white paint. To develop a long-term preservation strategy, the research focused on understanding the materials and construction methods used in Twombly's sculptures. In collaboration with the Chair of Non-Destructive Testing at the Technical University of Munich, the artworks were inspected using X-ray radiography and computed tomography. The results showed that Cy Twombly used various everyday objects made from wood, plastics, metal, and paper/cardboard to build the assemblages. Unexpectedly, the examinations revealed that the individual parts are solely held together by the coating of plaster and paint, lacking additional mechanical connections. The overall structure thus proved to be very fragile and highly sensitive to physical stresses, whether due to handling, transport, or strains in the microstructure caused by climatic fluctuations. Since little was known about Cy Twombly´s choice of materials and manufacturing details, the results offer valuable insights into the overall artistic process and decision-making of one of the most influential artists of the 20th/twenty-first centuries. Conservators can use the art-technological findings to monitor the sculptures ‘condition and develop or adapt long-term preservation strategies, including aspects such as ambient climatic conditions and handling storage and transport specifications. In addition, the knowledge generated can be used for further research on the specific materials and transferred to other artworks by Cy Twombly.

Reinforced Concrete Columns Insulated by Different Gypsum Layers Exposed to 900°C One Side Fire Flame

This study investigated the effect of high-temperature fire flame on reinforced concrete columns coated with a layer of gypsum insulation. Six samples were cast and cured in a hot water bath at 67°C, covered on one side by 10 and 20 mm thick layers of gypsum plaster. The samples were exposed to a 900°C fire flame in a hydrocarbon fire furnace for one and two hours. The results showed that the gypsum plaster layer prevented a high-temperature rise within the core of the column. The differences between all gypsum-coated columns varied compared to those of the reference samples. The gypsum-coated columns had reduced axial displacements and no spalling and visible cracks on their faces. The improvement in the compressive strength of concrete will be discussed in a future paper. This study was carried out following ACI-318 and ASTM C1529.

Use of Photogrammetry and Terrestrial Laser Scanning to Measure Superficial Weathering Damage on the Façade of Hanfelden Castle, Austria

Hanfelden Castle is one of the few Renaissance castles in Austria, which were subsequently hardly redesigned and changed since the tower building from the 14th century, and the extension in the 16th century to the today's appearance. This includes the façade with plaster layers from the 16th to the 18th century on the south and west side. Under these conditions, the concept for future scientific research of the object should essentially cover two needs: On the one hand, a collection of 3D basic data as complete as possible should be created for further work with the help of geospatial-technological methods, and on the other hand, methodological-technical expertise should also be built up (no substantial investigations have been undertaken in this direction). Additionally, and with regard to the determination of mostly conservation measures- the façade should be preserved - it has been important to check the façade made of plaster, natural stone or brick for the extent of superficial damage - such as weathering, flaking, bulging or bending. Therefore, non-contact 3D measuring systems are compared and applied as an alternative to visual inspection using standard cherry pickers or scaffolding. These so-called geospatial technologies applied in this study include methodological aspects of terrestrial photogrammetry, UAV assisted photogrammetry, and terrestrial laser scanning (TLS). This study used historical data/recordings and photogrammetric results from 1986 as well as newer techniques from the structure from motion (SfM) method (2019, 2022) and terrestrial laser scanning (2019, 2022). The different data recording methods and different result data in a multi-temporal and multi-sensoral approach, comparable for the changes to the facade, were a challenge for the study. Despite the different methodological approaches of the technologies used, the overarching goals of the study were, on the one hand, to detect and map the damage to the facade that has become increasingly apparent over the years. On the other hand, it has been shown that the applied 3D methods used (individually or in combination) represent a time-saving and cost-effective alternative to visual examinations using lifting platforms. The data sets obtained in the campaigns described should be homogenized and summarized in the sense of a historical BIM and serve as a basis for further work on the object. The focus was on multi- and interdisciplinarity as well as on taking into account the needs of science to science and science to public dissemination.

RESTORATION COMPOUNDS FOR TERRAZZITE PLASTER ON THE EXAMPLE OF CULTURAL HERITAGE SITES OF THE 20TH CENTURY (RUSSIA)

Inroduction: Gradual destruction of buildings or structures of historical significance is a natural process that cannot be stopped. Therefore, preservation of architectural monuments is one of the most important areas of restoration activity. Complete replacement of damaged building materials of architectural monuments changes the historical appearance, and thus cultural sites are stripped of their original look. Innovations in the re-creation of historical building materials and technologies help preserve historical continuity. The purpose of the study was to develop a number of compounds of terrazzite plaster mixtures for cultural heritage sites of the 20th century, which, from an aesthetic point of view, will not allow the loss of the natural and picturesque appearance of the monument, and will be able to preserve the “patina of time”. As a result of the research, the authors studied the compositions of the selected samples, proposed restoration compounds of terrazzite plaster, and determined the algorithm for applying an analogue of the historical plaster. In terms of technical and economic indicators, the developed restoration compounds are effective and make it possible to return architectural monuments to their original appearance with minimal costs. Based on the results obtained, conclusions were drawn about the feasibility of using the proposed new components in terrazzite plaster mixtures to increase strength and ensure high-quality adhesion of the old and new plaster layers. The proposed technology contributes to the return of architectural monuments to their original appearance without losing the historical authenticity of the buildings.