Stone Structures Research Articles

HYDROPHYSICAL PROPERTIES OF HEAVY-DUTY CONCRETE WITH A COMPLEX MODIFIER FOR HYDROMELIORATIVE CONSTRUCTION

Heavy concrete is widely used as the main structural material in irrigation and drainage construction, ensuring high reliability and safety of the complexes during operation. The main quality criteria for heavy concrete are their operational characteristics. The binder was Portland cement of class CEM I 42.5N. The dispersed composition, technological and strength characteristics of cement and cement stone obtained from it were determined using sieve analysis, pycnometric method, determination of bending and compressive strength in accordance with standard methods. Natural sand was used as a fine aggregate. Granite crushed stone was used as a coarse aggregate. Water was used to mix the concrete mixture. Melflux 5581 F superplasticizer was used as a plasticizing additive. Microsilica was used as an active mineral additive. Chopped basalt fiber was chosen for dispersed reinforcement of concrete stone. To determine the efficiency of water interaction with the matrix of the developed concrete and, as a consequence, the efficiency of diffusion processes inside the matrix, affecting the destruction of the concrete stone structure and possible moisture loss during irrigation, the porosity of concrete, its water absorption and water resistance were determined. Analysis of the obtained data shows that the introduction of a complex modifier together with basalt fiber reduced the water absorption index by 57.8% compared to the control. The water resistance of the modified concrete in composition 5 increased by 4 loading stages compared to control composition 1. Improvement of hydrophysical properties of modified concrete was established: water absorption decreased by 57.8%; water resistance grade increased by 4 loading stages in comparison with the control composition. After 600 cycles of frost resistance testing, the mass loss was 1.5-1.8%, the strength decrease was 9.1%-10.2%. The proposed modification with a complex additive together with basalt fiber allows obtaining high-quality heavy concrete with improved hydrophysical properties.

A Multicultural Archaeological Site on Bukowa Góra Hill in the Town of Dąbrowa Górnicza, Poland

There is a multicultural archaeological site on Bukowa Góra Hill in Dąbrowa Górnicza in Southern Poland. The chronology of megalith-type stone structures, barrow burial grounds and traces of ore mining extends from the Stone Age to the early Middle Ages.

Towards the Gothic: Design and Construction of the 12th Century Vaults in Notre‐Dame in Paris, and Possible Origins

ABSTRACT The vaults over the choir and nave of Notre‐Dame in Paris play a key role in the development of Gothic vaults—regarding their sheer height and span, and in particular their complex stone structure. A considerable dynamic in the development of new construction details can be seen in solutions that in some cases are still quite distinct from the well‐known constructions of the great Gothic vaults, and that in other cases, although innovative, remain more or less singular. The design of the sexpartite vaults follows a scheme established in the early Gothic and at the same time displays groundbreaking conceptions in geometry and construction. The fire of the roof that in 2019 damaged part of the vaults, but also showed their remarkable structural performance, brought up the necessity of better understanding these structures while also giving deep insight into construction details. The ongoing research presented here correlates geometric analyses based on 3D‐scanning, carried out on the vaults in Notre‐Dame and on comparable structures, observations on construction details on site, and sources such as historical drawings, with large‐scale experiments reproducing the processes of construction, fabrication of building elements, as well as planning and information transfer from design to building. The approach that refers to the built object as its principal source can be characterized as reverse engineering.

Improving the adsorption of cloud concrete stone porous aggregate to phase change materials by alkali modification

In this paper, the pore structure of cloud concrete stone (CCS) was optimized by alkaline hydrothermal treatment to improve its adsorption capacity for phase change materials (PCMs), thus enhancing the heat storage effect of phase change composite aggregates. The results showed that the adsorption rate of CCS modified by alkaline solution for 36 h was 21.49 %, which increased by 30.64 % relative to that without modification. The macroscopic and microscopic morphology showed that the 24-hour modified CCS appeared small cracks in the surface and the internal pores became more numerous. The 48-hour modified CCS appeared exfoliated on the surface and the internal pores and cracks increased. Hydrothermal treatment changes the pore structure of CCS, making it more conducive to the adsorption of PCM.

МЕХАНИЗМ ХИМИЧЕСКОГО ВЗАИМОДЕЙСТВИЯ ОРГАНИЧЕСКОЙ ДОБАВКИ БИОЛОГИЧЕСКОГО ПРОИСХОЖДЕНИЯ С КОМПОНЕНТАМИ КОМПОЗИЦИОННОГО ВЯЖУЩЕГО

A mechanism is proposed for the chemical interaction of an organic additive synthesized from the blood of cattle with the mineral components of a composite binder obtained by the joint mechanical activation of Portland cement and broken ceramic bricks. It has been established that the organic additive, interacting with the cations of inorganic components, forms a structure that is built into the frame, which provides plasticizing properties to the cement paste and contributes to the formation of a uniformly distributed fine-grained structure of the cement stone, which acquires increased strength, which is confirmed by the results of physical and mechanical tests. It has been determined that organic additives D-1 and D-2 are products of enzymatic hydrolysis of inedible bones, hooves, wool, and skin of cattle, differing in the time and conditions of hydrolysis. Additive D-3 is a mixture of polypeptides (oligopeptides), the molecular weight of which is less than the molecular weight of the original blood proteins and amino acids, which uses only protein hydrolyzate of cattle blood with a minimum content of sulfur-containing amino acids: cystine, methionine. As a result of hydrolysis, active amino and hydroxyl groups increase, which act as a surfactant; when interacting with water, these groups form a structure with two hydrosilicate groups: NH2 (amino group) and (carboxyl group), which interact with the minerals of Portland cement, cullet ceramic brick and water, binding it with amino groups. Organic additive D-3, interacting with cations of inorganic components, contributes to the formation of a uniformly distributed fine-grained structure of cement stone, which has increased strength, which is confirmed by research.

Degradation of Concrete Cement Stone Under the Influence of Aspergillus niger Fungi

The concepts of physical and chemical transformations occurring in cement concrete under conditions of microbiological deterioration can be used to control the processes of the destruction of cement concretes in order to ensure the required durability and to predict the service life of products. The study of changes in the structural and phase composition of cement stone made of Portland cement grade CEM I 42.5N in the process of fungal deterioration for 6 months when moistened, as well as a sample of a concrete wall exposed to fungal microorganisms for 20 years, was carried out. Diffractograms of the studied cement stone samples contain a large number of pronounced narrow peaks and indicate a highly crystalline structure of phases with the presence of an X-ray amorphous phase of calcium hydrosilicates and tobermorite gel in the cement stone. Changes in the structure of cement stone under the influence of fungi are confirmed by the data of a derivatographic analysis. A decrease in the content of calcium hydrosilicates and ettringite, as well as other crystalline phases in cement stone, leads to a decrease in compressive strength by about 15% over 6 months of fungal degradation. Similar changes after 20 years of exposure to microorganisms suggest deterioration in the strength characteristics of concrete.

A glimpse into daily life in an Ottoman harbour: Evidence from a cesspit in Ainos (Türkiye)

The daily life of non-elite people from the past is usually hard to evaluate, since historical sources largely concentrate on the upper classes. This knowledge can be gained by archaeological excavations and use of geo- and bioarchaeological methods. In 2021, geophysical prospections in Enez (Türkiye) revealed a circular stone structure. The excavators identified a latrine probably used from 17th until the 19th century. Palynological, palaeoparasitological and archaeobotanical methods have been applied for understanding the diet, hygiene and diseases of the people using the latrine. The cesspit was a closed round structure with walls made of stones. It had no contamination from outside and was filled with liquid or semi-liquid content with dissolved salts and organic matter derived from urine, faeces, kitchen waste, dung and other rubbish. Results show a broad diet including wheat, chili peppers, olives, spices, a wide range of fruits, meat, fish and oysters. This sanitation did not protect the inhabitants of the house from intestinal parasites in the forms of helminths whipworm, roundworm and the protozoan Giardia duodenalis that causes diarrhoea. The data highlight the special role played by the harbour of Ainos in the establishment and possible expansion of new food products from the New World.

Landscape positioning of Neolithic mustatil stone structures along the margins of the Nefud Desert, Saudi Arabia

Monumental rectangular stone structures called mustatils are an important emerging feature of the Holocene archaeological record of northwestern Arabia. To date, few have been excavated, with available radiocarbon dates suggesting an age range of ca. 5400–4200 BC. Here we present a rigorous spatial analysis to identify the patterning and landscape context of 169 mustatils in the southern and western margins of the Nefud Desert. This included: (1) a systematic survey of satellite imagery to identify mustatils; (2) viewshed analysis to examine location and landscape visibility; (3) a point process model to understand how diverse environmental and landscape variables affect mustatil locations; (4) mark correlation function to assess spatial patterning of mustatils based on their size. Results indicate that mustatil locations are determined most by proximity to water (likely locations of enhanced surface water occurrence under the enhanced humidity of the Mid-Holocene), on east facing slopes, close to rocky areas, at elevations between 880 and 950 masl, and on or near topographic ridges (positive topographic position index). Viewshed analysis showed that mustatils are preferentially located in areas that have good views, but not the best that are available, indicating complex landscape positioning that balances a range of topographic and behavioural factors. Using a rank permutation method with size (length) of mustatils as a proxy for labour mobilization we show that mustatils within clusters are not arranged hierarchically based on size, and were likely built by non-stratified groups of people. Our analyses show that people were choosing multiple factors when deciding where to build mustatils, and that the distribution of mustatils may relate to different groups of people resulting in the construction of complex ritual landscapes. As one of the earliest examples of large-scale monumental stone structure construction in global prehistory, understanding mustatils can enlighten us on human-environment interaction during the Neolithic.

Monitoring of Architectural Monuments

The article presents the main provisions that it is advisable to follow when organizing and conducting monitoring during the operation of cultural heritage sites. It is noted that the existing regulatory documents do not take into account the specifics of monitoring during operation, but are mainly aimed at protecting the monument from neighboring construction.Criteria are proposed to control the technical condition of historical buildings. Among them is the rate of development of long-term precipitation, which is considered as an indicator of the intensity of natural and man-made impacts on the building.Among them is the rate of development of long-term precipitation, which is considered as an indicator of the intensity of natural and man-made impacts on the building. It is noted that for stone structures, critical masonry stretching deformations serve as an effective criterion for the preservation of historical buildings, since in calculating the interaction of structures and foundations they are the primary criterion for calculating the second group of limiting states. In relation to it, the criterion of absolute precipitation and relative difference of precipitation is secondary. It is shown that over time, for buildings built on weak water-saturated clay soils, an increase in the unevenness of precipitation occurs. Special attention is paid to taking into account the accumulated uneven precipitation of buildings of historical development. The article presents the most characteristic types of deformations of buildings, among which in St. Petersburg the bend is most common, which is due to the regularity of building and rebuilding sections of urban neighborhoods.Monitoring is also considered as a reliable means of diagnosing the technical condition of the monument. The monitoring function is considered as a means of controlling the limitations of the monument’s operability, which continues to be operated in conditions of limited operational technical condition.

제주 돌문화 고찰

Jeju stone culture is a representative culture of the Jeju people, reflecting their perception of stones symbolized through their life experiences. In religious legends or geomantic tales, stones possess sacredness or function as objects of taboo and exorcism. In natural legends, stones as megaliths symbolize the tragedies of Jeju people's lives. In human legends, stones emphasize women's chastity and virtue. In folk songs, stones are borrowed or used as metaphors to express thoughts and emotions. As inanimate objects, stones represent solidity and dullness, and the metaphorical emotions are firmly pessimistic. Stone tools take advantage of strong friction, water resistance, and fire safety. In agriculture, the batdam (farmland stone walls) signifies the recognition of ownership and a boundary. As historical relics, stone structures like jatseong for raising livestock highlight the entire island as a national ranch. In folk beliefs, stones are worshiped and prayed to, with examples like dolmireuk (stone Maitreya) or bultap (stone pagoda) being objects of devotion for the desire to bear and raise children and for healing illness.

Developing the composition of fine-grained concrete from the waste of the mining and processing enterprise

The object of this study is fine-grained concrete from the waste of mining and processing plants. These wastes are fine-grained dusty sands of polymineral composition. Their use as an aggregate for concrete is restrained by high water consumption, which does not make it possible to obtain sufficient strength for concrete. Therefore, the problem to be solved was the substantiation of the composition of fine-grained concrete from these wastes with mineral and chemical additives, which would ensure obtaining physical-mechanical and hydrophysical properties reasonable for the production of construction articles. The composition of fine-grained concrete from the waste at the Poltava Mining and Processing Plant and slag Portland cement in a ratio of 3:1 and additives of micro silica (15 % of the cement mass) and polycarboxylate superplasticizer (2 % of the cement mass) with W/C=0.5 was obtained. The compressive strength of this concrete reaches 40 MPa, which exceeds the strength of fine-grained concrete of a similar composition on natural fine-grained sand by 3 times. This is due to a greater degree of cement hydration, a greater number of formed hydration products, the presence of silica and quartz particles, a more uniform alternation of gel, silica particles, and crystal hydrates in the structure of cement stone. As a result, the structure contains a larger number of electro heterogeneous contacts between particles and grains that have negative (quartz, calcium hydro silicates) and positive (crystal hydrates of portlandite, hydro aluminates and calcium hydrosulfoaluminate) surface charges. This is what determines the achieved strength and water resistance of fine-grained concrete. The resulting composition of fine-grained concrete is recommended for the production of construction articles.

Conservation of stone heritage buildings: Exploring the algicidal properties of biologically-synthesized nano-silver

The degradation of stone heritage buildings by pioneer plants such as algae is a major challenge in heritage conservation research worldwide. At present, there is a lack of effective algaecides to inhibit the growth of algae on stone structures, prompting an urgent need to explore effective green methods to remove algae colonizing on surfaces of stone heritage buildings. Therefore, we explored the use of aqueous and alcoholic extracts of four plant leaves (Cinnamomum cassia leaf, Syzygium aromaticum leaf, Thymus mongolicus leaf and Pogostemon cablin leaf) to prepare silver nanoparticles. By optimizing the synthetic parameters, we optimized the yield of the nanoparticles and examined their algicidal activities through in-vitro and in-situ experiments. The experimental results showed that the chlorophyll-a concentrations of algae treated with nano-silver synthesized from the alcoholic extract of Cinnamomum cassia leaf decreased approximately threefold, and the algae removal rate reached 71.34%. Meanwhile, nano-silver treatment made the color of the stone chips colonized with algae close to the color of the uncolonized algae, which demonstrated that the nano-silver can effectively remove the algae colonized on the stone chips. This study confirms that nano-silver synthesized from plant leaves offer a viable strategy as a ‘green’ algaecide for stone heritage buildings.

Scandinavian Erratics in the Cultural Heritage Sites of Western Poland

In north-western Poland, cultural and historical structures were erected using erratic boulders of Scandinavian origin. These structures have yet to be subjected to detailed analysis with the aim of determining their origin, type of erratic boulders and rock abundance of a given petrographic type. This topic has not been addressed by art historians in previous studies of similar structures. The objective of this paper is to present five illustrative examples of stone structures that are closely related to cultural heritage in north-western Poland. A comprehensive inventory of the stone material is presented, categorised according to petrographic types. This is accompanied by a guide to the erratics. Furthermore, this article addresses the principles of geoethics and the concept of sense of place, with the objective of fostering a sense of pride in cultural heritage among residents and viewers. The objective was to identify the current and potential future geosystem services that erratic boulders can provide at the aforementioned locations. The survey methods were non-intrusive and included a comprehensive analysis of the stone material at eye level. Furthermore, in addition to graphic and photographic archiving, the petrographic type of rock and the type of indicative erratics were identified in carefully designed test fields. The results were subjected to basic statistical calculations. The results obtained represent a new corpus of knowledge that can be employed in the sustainable development of the five regions through the utilisation of a tool such as geotourism. It is anticipated that the implementation of innovative initiatives aimed at fostering geoenvironmental awareness and providing educational benefits, such as disseminating knowledge about the petrography and history of the sites (including the evolution of stone workshops and techniques), the role of historic buildings in strengthening attachment to roots, and their promotion in the media and on the internet, will result in the attraction of a more diverse group of tourists with interests beyond the current tourist and recreational offerings.

Study on the Compatibility of Acrylic Acid-acrylamide-diethyldiallyl Ammonium Chloride Copolymer with Cement Slurry in CO2 Environment.

This paper investigates the structure and aggregation stability of acrylic acid-acrylamide-diethyldiallylammonium chloride (FA367), followed by an investigation into the impact of acidic CO2 environments on the interaction between FA367 and cement slurry. The results showed that FA367 formed stable flocculation in cement slurry filtrate, which was not affected by acid gas CO2. With an FA367 concentration of 0.6%, the fluidity of the cement slurry measures 18.1 cm, but this fluidity is lost upon introducing CO2. At 90 °C, the compressive strength after 1, 3, and 7 days is 10.23, 77.48, and 62.97%, respectively, compared to pure cement. However, with the addition of CO2, the compressive strength increases to 27.03, 99.59, and 75.47%, respectively. The interaction between FA367 and cement slurry impedes cement hydration without altering hydration product composition. Instead, it fosters needle-like aggregations between hydration products, affecting the cement stone's compact structure. Upon CO2 introduction, these needle-like structures diminish, resulting in an overall more intact cement stone structure.

Weathering Tests on Raw and Consolidated Vicenza Stone.

The preservation of cultural heritage, particularly historical stone structures, represents a very challenging matter due to several environmental and anthropogenic factors. Vicenza stone, a calcareous rock known for its historical significance and widespread use in architectural masterpieces, requires significant attention for conservation. In fact, as the demand for sustainable and effective preservation methods intensifies, the exploration of innovative consolidation strategies becomes essential. To this end, inorganic consolidants, based on alkaline silicate formulations and nano-silica, were explored for their promising performance in enhancing the surface properties and chemical stability of Vicenza stone. In particular, the durability of treated and untreated Vicenza stone samples was evaluated by means of accelerated weathering tests such as freeze-thaw cycles, salt crystallization and simulation of acid rain. The experimental results revealed that Vicenza stone is very resistant to the effects of freeze-thaw cycles and acid rain; both the accelerated weathering tests did not show significant differences between treated and untreated VS samples. A different behavior was detected for the test for resistance to salt crystallization, whose findings led us to deduce that, for this kind of degradation, it is possible to observe a more beneficial effect of the consolidation treatments on the stone durability.

Electrical resistivity tomography of a masonry bridge: assessing water infiltration on Prebends Bridge, Durham, UK

ABSTRACT Non-invasive imaging methods are a useful tool in informing conservation actions for historical buildings. Electrical Resistivity Tomography (ERT) is widely used in geophysics to image the subsurface but has been seldom used for non-invasive imaging of small-scale masonry structures. Here, we propose an adaptation of the method allowing non-damaging investigation of larger-scale stone structures. We report results of an ERT survey of Prebends Bridge in Durham, a heritage masonry structure constructed in 1778. Our assessment is based on data acquired on the paved top surface of the bridge, which is subsequently modelled and inverted with the use of open-source software. Final images of the internal structure of the bridge reveal areas of lower electrical resistivity, that we interpret as representing regions of water saturation. Locations of low resistivity areas are in good agreement with the structural defects and patches of seepage observed externally. These results will help inform remediation work, to preserve this historical structure from further water damage. In future studies, time-lapse imaging may help to highlight water pathways unambiguously (through comparison of dry/wet periods), while additional electrode arrays installed on the sides/base of the structure could be used to better constrain 3D internal structure.

X-Ray powder diffraction - structure prediction of unknown stone using foolproof and GSAS - Rietveld Refinement

A slightly violetish blue, cone shaped, hexagonally soft sheen, a soft lustre on a surface, and semi/nearly transparent with reasonable weight of a natural stone has been analysed as a part of investigation for determining the components of the stone thereby leading to identify as to whether the stone is in a category of gemstone, radioactive elements, or otherwise. Philips, X-pert Pro, DY993 X-ray Powder Diffractometer has been employed for collecting the powder diffraction data in the Bragg-Brentano geometry using proportional counter in the 5° < 2θ < 85° range at room temperature 300 K. The data, thus, obtained from the XRPD has been used in FullProf and GSAS (General Structure Analysis Software) software with the Rietveld refinement technique for elucidating the possible molecular structure of the unknown stone. In addition to the XRPD technique, the physical and optical parameters such as specific gravity, hardness, luster, transparency, cleavage, streak and other associated minerals have also been measured. This study reveals that the stone is in a category of precious stone which is of mineral deposition Corundum, a blue sapphire. The structure has been determined from Rietveld analysis in space group R-3c, with a= 4.7655 (2) Å and c = 13.0132(3) Å.

Новые памятники археологии на северном побережье Кандалакшского залива Белого моря

The article is devoted to the results of the archaeological expedition of the Kola Scientific Center of the Russian Academy of Sciences on the northern shore of the Kandalaksha Bay of the White Sea near the city of Kandalaksha and on the Kolvitsa River in 2023. Three new archaeological monuments have been recorded: Niva XXIII — boulder pit, Kandalaksha XVI – charcoal pits and Kolvitsa – stone structures. The boulder pit is located on an ancient sea terrace, on the western slope of Mount Volosyanaya, 1 km from the Niva River. Three charcoal pits are located on the northern shore of Malaya Pitkulya Bay, near the southern slope of Mount Krestovaya, not far from the labyrinth. This is the first discovery of such objects in Russian Lapland and they date back to the late 15th–16th centuries. Seven formations of boulders are located on the northern bank of the Kolvitsa River near the rapids. Analogs are known to them in other places of Russian Lapland. There are also boulder pits on the Khlebnaya River and on the coast of the Barents Sea. The dating and ethnicity of the boulder structures are still speculative.

In vitro Biomineralization Ability of Magnesium-Doped Coral Hydroxyapatite Coating Prepared by Pulsed Laser Deposition

Coral hydroxyapatite (CHA) is a calcium phosphate that has a similar inorganic composition to human bone and the porous structure of coral stone. Due to its interconnected network like pore structure, it can serve as a framework for bone conduction. In this study, CHA films and Mg-CHA films were deposited on titanium and silicon substrates by Pulsed laser deposition, and then the films were heat treated respectively. Studies on the adhesion of the coating showed that the heat-treated Mg-CHA film adhered better to the titanium substrate. The experimental study on biomineralization in vitro showed that a small amount of porous structure appeared in the heat-treated Mg-CHA after immersion in SBF for three days, and the porous structure was visible after immersion for seven days. After 14 days, a new apatite layer formed on the surface. This suggested that magnesium undergoes chemical corrosion in SBF, leading to rapid ion exchange, which results in the formation of porous structures and promotes the development of an apatite-like layer. In summary, the heat-treated Mg-CHA films had superior biomineralization properties.

A Romano-British Settlement at Hawbank Field, Skipton

An excavation in early 2021 investigated the remains of Romano-British settlement at Hawbank Field, on the north-eastern edge of Skipton. Activity had begun at least by the second century AD and extended into the late fourth or early fifth centuries, concentrated around a series of ditched and banked enclosures. Stone structures and surfaces and numerous ditches and pits were associated with the Romano-British settlement. Two inhumations were radiocarbon dated to the third-fourth century AD. Fragmentary remains, found alongside the Romano-British features, suggest some activity in the medieval period as the rest of the site was incorporated into an open field system.