Search Results (11)

This paper presents the results of research conducted as part of a bilateral cooperation project between National Research Council (Italy) and Chinese Academy of Cultural Heritage (China) for the conservation of the earthen walls of Ancient Ulanbay City (Xinjiang, China). In 2007 and 2012, conservation interventions were carried out on the remains of the ancient walls, focusing on areas at risk of collapse. This involved the construction of new adobe masonry (sun-dried earthen bricks and mud mortar) to support the ancient rammed-earth walls, which required consolidation treatments due to their exposure to weathering. In order to support the site’s conservation efforts, several nanoproducts were selected for testing as consolidants for the adobe bricks. Nano-silica (NanoEstel) and nano-lime (Calosil E25), with and without ethyl silicate, and a nano-calcium oxalate-functionalized ethyl silicate (SurfaPore FX WB) were tested and compared with commonly used products for surface consolidation. Ethyl silicate was applied alone as a reference treatment. The mixtures tested in this research had not been previously explored, thus offering new opportunities to identify suitable solutions for the consolidation of earthen structures exposed to environmental conditions. In this study, adobe bricks were sampled from the archaeological site, and the effectiveness of each treatment was assessed based on changes in chromatic appearance, cohesion, and water behaviour. The results showed different behaviours of nanoproducts. Nano-silica, alone or especially in combination with ethyl silicate, is overall more effective than nano-lime for the consolidation of earthen materials, thanks to its greater compatibility with these materials. Full article

As an important tangible carrier of historical and cultural heritage, ancient city walls embody the historical memory of urban development and serve as evidence of engineering evolution. However, due to prolonged exposure to complex natural environments and human activities, they are highly susceptible to various types of defects, such as cracks, missing bricks, salt crystallization, and vegetation erosion. To enhance the capability of cultural heritage conservation, this paper focuses on the ancient city wall of Jingzhou and proposes a multi-stage defect-detection framework based on computer vision technology. The proposed system establishes a processing pipeline that includes image processing, 2D defect detection, depth estimation, and 3D reconstruction. On the processing end, the Restormer and SG-LLIE models are introduced for image deblurring and illumination enhancement, respectively, improving the quality of wall images. The system incorporates the LFS-GAN model to augment defect samples. On the detection end, YOLOv12 is used as the 2D recognition network to detect common defects based on the generated samples. A depth estimation module is employed to assist in the verification of ancient wall defects. Finally, a Gaussian Splatting point-cloud reconstruction method is used to achieve a 3D visual representation of the defects. Experimental results show that the proposed system effectively detects multiple types of defects in ancient city walls, providing both a theoretical foundation and technical support for the intelligent monitoring of cultural heritage. Full article

As an important part of traditional Chinese architecture, Fuzhou’s ancient houses have unique cultural and historical value. However, over time, environmental factors such as efflorescence and plant growth have caused surface damage to their gray brick walls, leading to a decline in the quality of the buildings’ structure and even posing a threat to the buildings’ safety. Traditional damage detection methods mainly rely on manual labor, which is inefficient and consumes a lot of human resources. In addition, traditional non-destructive detection methods, such as infrared imaging and laser scanning, often face difficulty in accurately identifying specific types of damage, such as efflorescence and plant growth, on the surface of gray bricks and are easily hampered by diverse surface features. This study uses the YOLOv8 machine learning model for the automated detection of two common types of damage to the gray brick walls of Fuzhou’s ancient houses: efflorescence and plant growth. We establish an efficient gray brick surface damage detection model through dataset collection and annotation, experimental parameter optimization, model evaluation, and analysis. The research results reveal the following. (1) Reasonable hyperparameter settings and model-assisted annotation significantly improve the detection accuracy and stability. (2) The model’s average precision (AP) is improved from 0.30 to 0.90, demonstrating good robustness in detecting complex backgrounds and high-resolution real-life images. The F1 value of the model’s gray brick detection efficiency is improved (classification model performance index) from 0.22 to 0.77. (3) The model’s ability to recognize the damage details of gray bricks under high-resolution conditions is significantly enhanced, demonstrating its ability to cope with complex environments. (4) The simplified data enhancement strategy effectively reduces the feature extraction interference and enhances the model’s adaptability in different environments. Full article

Many regions of the world have traditional dwellings, which not only represent the main form of residential architecture, but also carry the local vernacular culture, display the region’s unique architectural style, materials and technology, and have important historical and cultural value. Due to environmental factors, traditional dwellings often suffer from architectural damage that threatens the stability of their structure and affects their esthetics value, resulting in a significant number of abandoned and demolished houses. In order to scientifically and effectively solve the damage problems of traditional dwellings, based on the theory of architectural pathology, the following diagnostic method for damage manifestation and the characteristics of traditional houses is proposed: “Architectural Pathology Appraisal–Pathological Environment Analysis–Mechanical Properties Testings”. The traditional dwellings in the ancient city of Guangfu were used as a case study for the practical application of the methodology for analyzing the main types and causes of the damage of the dwellings by examining the damage information of the dwellings, collecting the environmental data of the damaged walls, and testing the mechanical properties of the damaged walls. The results show that the main damage type in the ancient city dwellings of Guangfu is dampness damage, with corrosion deterioration, wall alkali flooding, and the moisture infiltration phenomenon as the manifested symptoms, and the damage is mainly concentrated in the lower part of the wall. In addition, the humidity and moisture content in the lower part of the wall is higher than that in the upper part of the wall, and the compressive strength of the damaged part of the wall is lower than that of the undamaged part. The humid environment of the old town contributed significantly to the destruction of the dwellings, and water intrusion led to a reduction in the strength of the dwellings’ bricks. Through the diagnostic method of building pathology, the causes of Guangfu dwellings’ damage are identified, and scientific and targeted damage intervention suggestions are made. This is expected to provide guidance for the treatment and prevention of building pathology in the ancient city of Guangfu and serve as a reference for the diagnosis and treatment of pathology in traditional dwellings in other areas. Full article

Ancient Ardaxšīr Khwarrah, today known as Shahr-e Gur, situated near the modern town of Firuzabad in Fars, Iran, holds historical significance as the inaugural capital city of the Sasanian Empire. During archaeological excavations conducted in 2005 by an Iranian–German team directed by Mas‘oud Azarnoush and Dietrich Huff, a mud-brick complex was uncovered, revealing a remarkably well-preserved stretch of wall painting and a polychrome painted floor. The discovery prompted the hypothesis of a potential funerary context dating back to the Sasanian period. Both the wall painting and painted floor have suffered extensive deterioration attributed to the environmental conditions of the archaeological site, which was inscribed on the UNESCO World Heritage List in 2020. To address the urgent need for preservation and further understanding of the site’s artistic and structural elements, an emergency diagnostic project was initiated. Non-invasive investigations were carried out on the wall and floor by optical digital microscopy and portable energy-dispersive X-ray fluorescence. Additionally, representative minute samples underwent analysis through various techniques, including micro-X-ray fluorescence, polarised light microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, micro-Raman spectroscopy, micro-Fourier Transform Infrared Spectroscopy, gas chromatography-mass spectrometry and pyrolysis coupled with gas chromatography-mass spectrometry. The palette of the floor and mural paintings were identified to contain red and yellow ochres, lead-based pigments, carbon black and bone white. The unexpected presence of Egyptian blue mixed with green earth was recognised in the green hues of the wall painting. The detection of protein material in both the wall painting and polychrome floor indicates the use of “a secco” technique, thereby shedding light on the artistic practices employed in Ardaxšīr Khwarrah. Full article

As a result of environmental and human influences, several types of surface deterioration emerge on historic buildings, resulting in a decline in the quality of these structures and even threats to their safety. In the conventional approach, assessing the surface damage on a structure involves the time-consuming and labor-intensive judgment and evaluation of trained professionals. In this study, it is suggested that the YOLOv4 machine learning model be used to automatically find five types of damage to historical gray-brick buildings. This would make the job go more quickly. This study uses the gray-brick wall buildings in the buffer zone of the global cultural heritage in Macau as an example. In total, 1355 photographs were taken on-site of the gray-brick walls, and the five most common types of damage were identified. By slicing and labeling the photos, a training set of 1000 images was created, and through 200-generation model training, the model can accurately identify and effectively identify the damage state of the gray bricks and enhance the quality judgment and evaluation of the exterior walls of historical buildings. Experiments allow us to reach the following conclusions: (1) The damage to the gray-brick ancient buildings in Macau is affected by the subtropical maritime climate. Missing paint, stains, and cracks are the main contributors to gray-brick wall damage. (2) Machine learning can help determine the type of damage to old gray-brick buildings, which is useful for managing and protecting historical buildings. (3) The model in this study can identify five types of damage: missing, cracking, plant or microbial erosion, yellowing, and pollution on the exterior walls of ancient gray-brick buildings. It is helpful to accurately identify and evaluate the damaged condition of the gray-brick wall and formulate corresponding protection schemes. Full article

The Fatimid state was established in Egypt in 969 and lasted until the end of the dynasty in 1171. During the Fatimid rule in Egypt, a large set of monuments were erected. A significant portion of these monuments were shrines dedicated to the descendants of the Prophet Muhammed, especially in Aswan. Groundwater rising, at present, has introduced severe deterioration to the ancient earthen mud-brick architecture of the Fatimid tombs in Aswan city (Egypt). However, monitoring the influence of anthropogenic and environmental aspects on the deterioration issues in Fatimid tombs has not yet been considered. To this end, the scope of this pilot study is to investigate the structural stability and weathering vulnerability of the building materials of mud-brick structures in the Fatimid Cemetery before restoration labor. This was achieved using an integration of remote sensing (Landsat 8 and SRTM-DEM) and hydrogeological datasets in the Geographic Information System (GIS), along with a physicochemical and mineralogical analysis of various materials (the bearing soil, wall plasters, and Muqarnas) from the affected cemeteries. The morphological and mineralogical compositions of the collected samples were analytically examined by using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) and CT scan. Moreover, geotechnical studies were conducted for the perched soil water and subsoil, including the analysis of the physiochemical composition and heavy metals using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results of multitemporal analysis of land use/land cover (LULC) changes displayed the growth and appearance of wetlands near the Fatimid tombs area over the last decades, boosting the geo-environmental risks from soil water rising. Furthermore, the detailed analytical investigations of building materials and soil foundations showed that this unique and substantial ancient Islamic archaeological site of Egypt shows weak geotechnical properties, and it is highly sensitive to natural and anthropogenic stressors. This innovative methodology can produce novel recommendations and results to the Ministry of Antiquities in Egypt and the Heritage Commission in Saudi Arabia for the adequate restoration of monuments. Full article

The preservation and restoration of heritage sites have always been of key focus in the field of cultural relics. Current restoration methods mainly involve physical or chemical techniques, which are in many cases intrusive, destructive, and irreversible. Hereby, we introduce a novel biological strategy (microbial-induced carbonate precipitation (MICP)) to repair natural and simulated surface cracks on six hundred years’ old wall bricks (part of the Nanjing City Min Dynasty ancient wall, China). X-ray micro computed tomography (X-ray micro-CT) was employed to non-destructively visualize the internal structure of the MICP-treated brick cubes. The results showed that MICP can effectively repair both natural and simulated cracks present on the brick’s surface. The compressive strength of the MICP-treated brick cubes was significantly higher than that of the untreated control cubes (33.56 ± 9.07 vs. 19.00 ± 1.98 kN, respectively). MICP significantly increased the softening coefficient and decreased the water absorption rate (p < 0.05), indicating that the water resistance of the wall bricks can be improved after treatment. The 3D images from X-ray micro-CT, a method that could non-destructively assess the internals of such cultural structures, showed that MICP can effectively repair ancient relics, promoting durability and limiting degradation without affecting the structure. X-ray diffraction analyses showed that MICP generates the same calcite form as that of original bricks, indicating that MICP filler is compatible with the ancient city wall brick. These findings are in line with the concept of contemporary heritage preservation. Full article

Among all geophysical techniques, electrical resistivity and magnetic surveying as an integrative approach has been used widely for archaeological prospection at different scales of investigations. In this study, DC resistivity (1D vertical sounding and/2D/3D ERT) and magnetic surveys (total and gradient) as a multi-scale approach was applied in a highly terraneous archaeological site (Tell) with a case study to characterize and image the various archaeological assets at different depths with different spatial resolutions. Four critical zones of great interest within the considered Tell were surveyed. At the heart of the study area, three layers were depicted clearly from 1D resistivity sounding. A thick conductive zone of mostly clay is sandwiched between two resistive layers. The topmost layer contains construction debris (dated back to the Islamic Era), whereas the deeper layer could be related to Gezira sand on which the probable Pharaonic temple was constructed. A long 2D ERT profile using Wenner Beta (WB) and Dipole–Dipole (DD) arrays with a 5-m electrode spacing identified shallow high resistivity anomalies that could be related to construction ruins from fired bricks. Additionally, it succeeded in imaging the turtleback-shaped deeper resistive layer of mostly sand. At an elevated rim to the east and west of the Tell, total and vertical magnetic gradient maps clearly delineated different archaeological structures: the walls of the rooms of ancient Islamic settlers and the walls of water tanks from the Byzantine Era. Magnetic modeling assuming 2.5-dimensional magnetic models constrained by the 2D ERT inversion models could be used to create a realistic representation of the buried structures. Toward the northern part of the Tell, the joint application of the quasi-3D ERT inversion scheme and the magnetic survey revealed an anomaly of a well-defined geometric shape of an archaeological interest thought to be a crypt or water cistern based on nearby archaeological evidence. The overall results of the geophysical survey integrated with the image of some partially excavated parts provided the archaeologists with a comprehensive and realistic view of the subsurface antiquities at the study area. Full article

Adobe constructions were widespread in the ancient world, and earth was one of the most used construction materials in ancient times. Therefore, the preservation of adobe structures, especially against seismic events, is nowadays an important structural issue. Previous experimental tests have shown that the ratio between mortar and brick mechanical properties (i.e., strength, stiffness and elastic modulus) influences the global response of the walls in terms of strength and ductility. Accurate analyses are presented in both the case of unreinforced and reinforced with fiberglass mesh when varying the mechanical properties of the materials composing the adobe masonry structure. The main issues and variability in the behavior of seismic resisting walls when varying the mechanical properties are herein highlighted. The aim of the overall research activity is to improve the knowledge about the structural behavior of adobe structural members unreinforced and reinforced with fiberglass mesh inside horizontal mortar joints. Full article

Materials that store the energy of warm days, to return that heat during cool nights, have been fundamental to vernacular building since ancient times. Although building with thermally rechargeable materials became a niche pursuit with the advent of fossil fuel-based heating and cooling, energy and climate change concerns have sparked new enthusiasm for these substances of high heat capacity and moderate thermal conductivity: stone, adobe, rammed earth, brick, water, concrete, and more recently, phase-change materials. While broadly similar, these substances absorb and release heat in unique patterns characteristic of their mineralogies, densities, fluidities, emissivities, and latent heats of fusion. Current architectural practice, however, shows little awareness of these differences and the resulting potential to match materials to desired thermal performance. This investigation explores that potential, illustrating the correspondence between physical parameters and thermal storage-and-release patterns in direct-, indirect-, and isolated-gain passive solar configurations. Focusing on heating applications, results demonstrate the superiority of water walls for daytime warmth, the tunability of granite and concrete for evening warmth, and the exceptional ability of phase-change materials to sustain near-constant heat delivery throughout the night. Full article