Brick Structures Research Articles

Heritage clay brick characterization and assessment with compatible contemporary bricks for retrofitting of heritage monuments

Various mughal architecture clay brick masonry monuments were built in the Punjab state of northern India from the late 14th to late 19th centuries. Nanakshahi monuments (era of 1st Sikh Guru-Guru Nanak Dev Ji) are gigantic clay brick masonry structures constructed of lime and lime surkhi mortar (a powdered form of red burnt clay brick). Currently, this study is focused on identifying a suitable material for repairing and strengthening heritage clay brick monuments. Using the mineralogical composition of heritage Nanakshahi clay bricks (NSCB), the study compares them with contemporary clay bricks (CCB) from the same region, and then compares them to newly prepared clay bricks (NPCB), which have similar composition and dimensions to NSCB. The X-ray fluorescence confirms that the NSCB samples of southeast Punjab have an elemental composition consisting of filler SiO2 and binding elements like Al2O3, Fe2O3, CaO, K2O and MgO. The average density of ancient NSCB and CCB has been found to be similar; the ancient NSCB has a lower water absorption rate and porosity in contrast to the present-day clay bricks. The Initial rate of absorption of an ancient NSCB is quite higher. In comparison to the heritage NSCB, the CCB's compressive strength value is lower and uniaxial compression strength of newly prepared clay bricks (NPCB) of similar mineralogical composition and dimensions is comparable to that of the heritage NSCB from Punjab districts. The significance of the study is to suggest a compatible material for strengthening of heritage clay brick monuments of northern India.

Crack Evolvement of Ancient Brick Masonry Under Uniaxial Compression Fatigue Loading

ABSTRACT Cracking is an essential intuitive indicator of damage in masonry structures. Evaluating the progression of fatigue cracks in ancient brick masonry structures is vital for the preservation and safety of ancient buildings. By conducting amplitude cyclic uniaxial compression tests on ancient brick masonry specimens, using the video image correlate-3d (VIC-3D) technology to collect images of the entire process from loading to failure, the development of fatigue cracks is analyzed and concluded. A reversed S-shaped function for fatigue crack evolution was established based on the fatigue damage mechanism. The model parameters’ physical significance, value range, and their impact on the model curve were discussed. The fatigue damage evolution equation was derived from the fatigue crack evolution model. The research results show that a reversed S-shaped function for fatigue crack evolution covers various types of fatigue crack evolution laws, with strong adaptability and high accuracy. The damage evolution curve established, based on the fatigue crack evolution model, has a reversed S-shaped change rule, and was divided into three stages: the first stage (0 N f ~ 0.1 N f ) fatigue damage grows faster; the second stage (0.1 N f ~ 0.9 N f ) fatigue damage growth is stable, close to linear change; when the cycle ratio exceeds 0.9, it enters the third stage, and fatigue damage increases rapidly.

Assessment of Compressive Strength of Concrete Using the CAPO Test

The CAPO-Test or the Cut and Pull-Out test, also known as the pull-out test, is gaining popularity as a method for estimating the compressive strength of existing concrete structures due to its reliability, less structural damage compared to core collection, and quick in-place strength. The manufacturer of the pull-out machine has provided a general correlation for assessing the in-place concrete strength of stone chip-based concrete. Many of the concrete buildings in Bangladesh are made of brick chip-based concrete. In a few projects in Bangladesh, the CAPO test has been used to assess the concrete strength of existing structures. However, the reliability of this test for concrete made of brick chips has yet to be investigated. 20 columns from five distinct structures, which varied in age from 14 to 45 years at the time of testing, underwent the CAPO and core tests for this study. Based on the fundamental findings of this investigation, a general correlation has been established regarding concrete composed of brick chips. According to the findings, the CAPO-Test f or concrete with brick chips shows estimated strengths using the proposed correlation varies between 0% and 30% of the core strength. No prior research has been identified on evaluating the concrete strength of existing structures containing brick chips using the CAPO test; therefore, this study supports the CAPO-Test's reliability in conducting in-situ concrete strength assessments of brick chip-based structures. Journal of Engineering Science 15(1), 2024, 1-10

Damage assessment method of clay brick masonry load-bearing walls under intense explosions with long duration

The vulnerability of clay brick masonry load-bearing (CBML) walls under low-intensity explosions has been extensively investigated. In recent years, large-scale explosions have raised wide concerns about the destructive effect of intense explosions. Intense explosions induced by large TNT equivalent explosives usually cause severe damage to building structures within several kilometers. Although the damage of building structures under intense explosions and normal low-intensity explosions might be different, the differences have yet received any attention in previous studies. Therefore, this study numerically investigates the dynamic performance of CBML walls under intense explosions with long duration (IELD). Firstly, the numerical model is validated by reproducing experimental records. Then the verified model is utilized to investigate the dynamic response and dynamic modes of CBML walls under IELD. Based on the identified failure mechanism, the effects of several parameters such as axial compression ratio, compressive strengths of masonry materials and wall geometry on the damage degrees of CBML walls are analyzed in detail. The damage index based on the residual axial loading capacity of CBML wall is proposed for damage evaluation. The damage assessment method is established for CBML walls under IELD, which can help to evaluate the damage level of clay brick masonry structures under far-field intense explosive scenarios.

Safety and behavior of implantable electronic devices during cremation

BackgroundThe current standard of practice for cremating patients with cardiac implantable electronic devices (CIEDs) is surgical explantation before cremation to mitigate the risk of device explosion. This surgery may conflict with patient or family beliefs, whereas cremation of CIEDs may create occupational hazards. ObjectiveThis study sought to establish an ex vivo model for screening CIED behavior during cremation. MethodsSeven CIEDs underwent testing including projectile/sound testing, impact testing, and gas analysis. In the projectile test, devices were heated until thermal failure (explosion) and filmed with a high-speed camera and microphone. For impact testing, brick structures were built to assess damage after explosion. Gas chromatography–mass spectrometry identified released gases. Findings were compared with occupational health standards, where available. ResultsThe implantable loop recorder and leadless pacemaker produced minimal kinetic energy and impact risk with thermal failure. The remaining devices demonstrated explosive disintegration at thermal temperatures <500°C. The pacemakers and implantable cardiac defibrillators produced sound levels >120 dB and resulted in damage to brick structures. Small quantities of benzene and hydrogen fluoride were produced but at quantities within acceptable occupational exposure limits in a cremation chamber. ConclusionAll tested CIEDs experienced explosion at temperatures below crematorium standards. The smallest devices produced minimal risk of damage or injury, suggesting that they may safely remain in situ during cremation, whereas the larger devices produced more kinetic energy, testing chamber damage, and louder explosions, suggesting potential risk with cremation. Cadaveric testing in full-sized cremation chambers is required to determine real-world risk.

Indoor temperature and CO[formula omitted] in South African primary school classrooms: Inspecting brick, container, and prefab structures

In the resource-constrained education sector in South Africa, infrastructure deemed temporary or backup elsewhere is used as permanent classrooms, mainly in areas of low income. Temperature and CO2 levels, substantial determinants of air quality, have not been studied across different classroom types, despite their direct impact on children’s cognitive performance and comfort. We measure CO2 and temperature every 11 min in 24 classrooms at two schools in Stellenbosch, South Africa. Container classrooms with and without insulation, mobile (prefabricated) classrooms, and brick classrooms of different configurations are included. Measurements were concurrently sampled over twelve months, across multiple seasons with relevant metadata, including ambient weather conditions. We analyse temperature and CO2 concentrations for classroom types and classroom categories and compare school days with non-school days. The results show that temporary classrooms (container and mobile) have substantially worse thermal environments, even when air conditioning is available. The CO2 concentrations in container classrooms are substantially worse, whereas mobile classrooms have better conditions comparable to brick classrooms. We conclude that container classrooms have the worst temperatures and ventilation, prefabricated classrooms have acceptable ventilation but poor thermal qualities, and brick classrooms have the best thermal environment and ventilation.

Medieval and Restoration Bricks: Water Transport (Hygric) and Microstructural Properties – A Compatibility Study

ABSTRACT The aim of this work was to analyze and ascertain the physical, hygric and mechanical properties of historical bricks, in order to deepen knowledge about the properties of existing historical building brick structures. Laboratory tests, such as density, water absorption and compressive strength, were conducted. In order to assess the microstructural characteristics of the tested bricks, mercury intrusion porosimetry (MIP) tests were performed. These tests were conducted on clay bricks from four medieval buildings (14th Century) of great historical significance, as well as on those currently produced, in order to identify the similarities and differences between specific groups of material properties. The results of this study and previous research will form a basis for creating a database of complete information in terms of physic, hygric and mechanical properties of historical bricks from different time periods, from the Middle Ages to modern times. The results will supplement modeling programmes utilizing materials specific to Polish construction periods, which can help simulate, as closely as possible, humidity transfer in real conditions. Moreover, the results will lead to the development of a useful tool for selecting materials in restoration processes, that will correspond with those used historically.

Optimization of Composition of Waterproofing Material Based on Modified Fine-Grained Concrete

The purpose of the research described in this article was to optimize the compositions based on hydraulic-modified binder and construction waste for waterproofing and repair of concrete or brick structures in contact with the ground, as well as the study of properties and development of the basis of the methodology for selecting the composition of such a waterproofing system. Processing of the results of the experiment was carried out by statistical and analytical methods. The research was based on a method for determining the adhesive strength of a waterproofing coating, based on the determination when the insulating layers are torn off. As a result of the calculation and experimental verification, the composition of the waterproofing material was obtained, which corresponds to an adhesive strength of 3.8 MPa; the strength of the waterproofing layer was 36–37 MPa, as well as the amounts of the main components: acrylic resin 3.9%; finely ground concrete waste 80 kg/m3; plasticizer consumption (0.38…0.39%) at the optimum moisture content of the base surface (9.7…9.8%).

Research on the Indoor Thermal Environment of Several Traditional Chinese Residential Buildings

To study the indoor thermal environment characteristics and influencing factors of traditional Chinese residential buildings, the existing research studies on the indoor thermal environment of traditional residential buildings were collected and organized, and the relevant measured data was extracted using GetDate software. After data analysis, the construction characteristics of brick and wood structures, wood structures, and raw soil structures were summarized. The indoor and outdoor temperature changes of the residential buildings in summer and winter were revealed. Finally, the indoor thermal environment characteristics and influencing factors of three types of traditional residential buildings were summarized. The research results can provide a reference for the construction and low-carbon renovation of traditional residential buildings.

Sustainable Geopolymer Structural Insulation Panels Obtained with the Addition of Power Plant Ash and Furnace Slag with Potential Uses in the Fabrication of Specialized Structures

The paper describes the process of obtaining geopolymer composites using raw materials from critical waste, i.e., mixed power plant ash and furnace slag powder. Using such geopolymer composites, structural insulation panels were made in the laboratory, which were subjected to tests specific to construction applications. At the same time, some special properties, such as sound insulation and electromagnetic shielding properties for special applications, were tested. The results obtained from the functional tests led to the conclusion that the panels made of geopolymer composites provided both sound and electromagnetic attenuation values clearly superior to those obtained from autoclaved cellular concrete, brick, or concrete structures, which encourages us to suggest such material concepts for complex shielding purposes. The sustainability of the technology for producing such geopolymer composites was fully demonstrated from the economic, environmental, and social perspectives.

Information Acquisition and Seismic Damage Prediction of Masonry Structures in Rural Areas Based on UAV Inclined Photogrammetry

Using a novel methodology that integrates incremental dynamic analysis (IDA) and unmanned aerial vehicle positioning (POS) analysis, this study aims to assess the seismic risk of brick structures in rural China. This method can collect a lot of data and accurately anticipate seismic damage by combining UAV oblique photography with IDA analysis. Because rural China has many masonry structures, the project will design unique seismic risk mitigation strategies. High-resolution cameras on Unmanned Aerial Vehicles capture realistic photographs of rural brick buildings. The collected data is carefully examined to reveal architectural and structural elements. The project uses dynamic post-processing software from the CHC Geomatics Office to improve UAV-reference station position accuracy. This program analyzes UAV POS data disparities. The findings allow rural Chinese brick buildings to be assessed for seismic sensitivity during unexpected ground shaking occurrences. UAV tilt-photography reduces manpower and expenditures, improving inquiry efficiency. This combination improves seismic risk response. The IDA and UAV POS analysis are essential for earthquake preparedness and risk mitigation. This data-driven method informs lawmakers, urban planners, and disaster management authorities worldwide, improving earthquake engineering and catastrophe resilience programs. This work improves seismic threat assessment and masonry structure fortification, making earthquake-prone buildings safer. Thus, rural communities benefit from it.

Fine proportions of demolition waste recyclates in terms of functionality and application possibilities in building mixtures

A specific component of demolition waste from concrete and brick structures is the fines that remain after processing into granular recyclate and after sorting out the coarser fractions. In addition to brick and concrete recyclate, this can also include materials such as glass, ceramics (tiles, sanitary ware...), rubber and ornamental stone. These fine-grained wastes in this paper, a systematic review of fine-grained recyclates is elaborated with specification of their nature (inert-active) and a summary of their properties, or their modifications, to achieve the declared functionality. At the same time, an overview of the application possibilities (types of construction mixtures) in which the fines can contribute to the achievement of specific properties (e.g. self-compacting concretes, decorative plaster, mortars, railway concrete sleepers...).

Results of the latest interdisciplinary research conducted in the Church of St. James in Sandomierz

The article is a summary of interdisciplinary research conducted in the 13th-century Dominican Church of St. James in Sandomierz in May 2022. The research included an archaeological survey located at the junction of the presbytery and the nave, followed by an architectural and historical-artistic analysis of the discovered walls and architectural details. The aim of the work was to obtain new materials regarding the beginnings and subsequent transformations of the church of St. James. In addition to traditional research and documentation methods, digital technologies were used, i.e. digital photography, laser scanning and photogrammetry. The stages of archaeological work recorded in this way could be incorporated into the existing digital 3D model of the entire monastery complex. Archaeological methods, as well as preserved source materials (textual and iconographic) were used to date individual structures. Due to later excavations (related to reconstructions and burials), the relationship between the layers recorded in the excavation did not create a clear sequence and cannot be the basis for findings regarding chronology. The initial dating was therefore based on the relationship between the walls and on the dimensions of the discovered bricks. It was established that the brick foundation marked as k. 43/44 may come from the 13th century and constitute a fragment of the unpreserved choir partition of the church – this hypothesis will require verification in the future. Additionally, a previously unknown, possibly medieval wall with a NS course (k. 3) on the line of pillars between the naves was uncovered, as well as a vaulted ceiling of the vestibule of the crypt under the Martyrs’ Chapel. The discovered architectural details include a fragment of a 13th-century ceramic molding, perhaps coming from the choir partition, and stone floor slabs. The discovered brick structures, architectural details and traces of numerous secondary excavations prove that the examined part of the church has undergone numerous transformations over the centuries and was intensively used for burials.

ОЦЕНКА МОРОЗОСТОЙКОСТИ КЛАДОЧНЫХ СТЕНОВЫХ ИЗДЕЛИЙ С УЧЕТОМ МЕТОДИКИ ВЛАГОНАСЫЩЕНИЯ В РОССИЙСКИХ НОРМАХ И СТАНДАРТАХ.

In order to improve the Russian codes in the field of brick and masonry structures, a comparative analysis of frost resistance assessment of masonry wall products of wide application in construction practice was carried out. The Russian codes revealed inconsistencies in the assessment of frost resistance of masonry products. In particular, in SP 15.13330.2020 [2] and GOST 7025-91 [4] one index F for determining the frost resistance of ceramic, silicate products, as well as the frost resistance of concrete, expanded clay and cellular concrete blocks, which misleads consumers and designers. In order to eliminate the noted inaccuracies, the article gives proposals for adjustments to SP 15.13330 and GOST 7025.

Half-scale shaking table tests of two brick and wood buildings: Effect of the engineered cementitious composites strips retrofit system

In order to study the feasibility of using the retrofit system of engineered cementitious composites (ECC) strips for strengthening Chinese rural brick and wood structures. Two half-scale buildings, one was the unreinforced building and the other was reinforced by ECC strips, were placed on the shaking table to apply various levels of seismic excitations. The comparisons between the unreinforced building and the retrofit building were analyzed regarding the natural frequency, maximum responses of acceleration and displacement, as well as the dynamic characteristics, torsion effect, global hysteresis response, and seismic behavior evaluations. Test results demonstrated that the ECC strips retrofit system significantly enhanced the stiffness, ductility, damage tolerance, and reduced the seismic displacement response of the structure. Meanwhile, the retrofit building was able to dissipate more energy with increasing magnitudes of earthquake excitation. Such an in-depth analysis provides a reference for the application of ECC strips to retrofit brick and wood structures.

Mesoscale analysis of fracture process in brick masonry structures

This paper deals with mesoscale analysis of masonry structures, which involves fracture propagation in brick units as well as along the masonry joints. The brick–mortar interfaces are incorporated in standard finite elements by employing a constitutive law with embedded discontinuity. Macrocracks in bricks are modelled in a discrete way using the same methodology, without any a-priori assumptions regarding their orientation. The proposed approach is computationally efficient as it does not explicitly require the discretization of joints. The accuracy of the approximation is first assessed by comparing the solution with a detailed mesoscale model incorporating interface elements. Later, a numerical study is conducted involving simulation of various experimental tests on small masonry assemblages, as well as single-leaf masonry walls, with running bond pattern, subjected to in-plane loading. The results clearly demonstrate the predictive abilities of the proposed simplified approach.

High-strength AlCoCrFeNi2.1 eutectic high entropy alloy skeleton with hollow brick wall structures by selective laser melting

In this work, a hollow brick wall structure was introduced into the preparation of AlCoCrFeNi2.1 EHEA to realize a skeleton structure by taking advantage of the good castability of eutectic high entropy alloys (EHEAs) and high cooling rate of selective laser melting (SLM). The effects of processing parameters on eutectic microstructure and mechanical properties of SLM-ed AlCoCrFeNi2.1 EHEA skeletons were investigated. With increasing volume energy density (VED), the microstructure along the building direction evolved from cellular structure to the coexistence of cellular and lamellar structures. The phases in the SLM-ed AlCoCrFeNi2.1 EHEA skeletons contained BCC/B2 and FCC phases. Under the VED of 137.25 J/mm3, SLM-ed skeletons with hollow brick wall structures had a compressive strength of 241.2 ± 4.2 MPa. The mechanical properties from tensile tests exhibited a yield strength of 1349.4 ± 12.4 MPa and an ultimate tensile strength of 1529.5 ± 12.8 MPa. The superior performance of the selective laser melting method was attributed to fine grain strengthening, dislocations strengthening, and heterogeneous structure of FCC and BCC/B2. This work provides possibilities for microstructure design and performance improvement of EHEAs and expands the avenue for developing advanced high-strength lightweight structural and energy-absorbing alloys.

An analytical model for determining realistic tensile strength and fracture toughness of fired clay bricks

The crack resistance of fired clay bricks is crucial for the safety design of brick masonry structures and needs to be evaluated reasonably. However, the realistic fracture parameters are extremely difficult to predict owing to the porous and defective characteristics of bricks. Thus, this paper aims to determine the tensile strength (ft) and fracture toughness (KIC) independent of size for fired clay bricks, which are rarely reported in previous studies. The fracture mechanisms of the bricks were elucidated using the fracture tests on brick specimens having varied sizes and notch lengths. Considering the material heterogeneity and discontinuity, the maximum fracture load (Fmax) correlates linearly with ft and KIC according to boundary effect model. ft and KIC can be predicted directly once only Fmax is determined from the test. The results showed that the predicted ft and KIC were generally independent of notch length and specimen size. Using statistical analysis, the means and upper and lower limits of ft and KIC were determined. Moreover, the predicted ft and KIC of bricks proved to be suitable for recycled brick aggregates with particle sizes of 5–40 mm. Thus, the crack resistance of the brick aggregates was clarified based on the proposed analytical model.

Advancements in Thermoluminescence Dating: A Case Study of Medieval Brick Structures in Azerbaijan

The study aimed to improve the precision of dating historical landmarks, specifically the Ballabur castle in Lenkaran, Azerbaijan Republic, using the thermoluminescence dating (TL) method. The annual dose rate, calculated with a -spectrometer equipped with a hyper-pure germanium detector, was found to be 2.98±0.19 mGy/year. By employing an online dose rate and age calculator, the sample's age was determined to be 920±50 years, consistent with the historical estimates of this region.&#x0D; &#x0D;

Out-of-plane flexural behavior of brick masonry strengthened with engineered cementitious composites embedded in the horizontal mortar joint

Unreinforced masonry (URM) structures exhibit high vulnerability under out-of-plane loads. Engineered cementitious composite (ECC) is suitable for the reinforcement of URM structures due to its excellent mechanical properties. This study presents a promising method to strengthen brick masonry structures using ECC embedded in the horizontal mortar joints. In order to investigate the flexural behavior of brick masonry strengthened by the proposed method under one-way horizontal bending loads, a total of nine groups of masonry specimens were tested under four-point bending loads, including one group of un-strengthened specimens and eight groups of ECC-strengthened specimens. The mix proportion and reinforcement ratio of the ECC were considered as variables in the experimental schemes. The failure mode, load–displacement curves, stiffness, strength, energy dissipation capacity, and ductility of the specimens were discussed. The test results demonstrate the effectiveness of this strengthening system in improving the out-of-plane performance of URM structures. The tensile properties of the ECC were closely related to the out-of-plane flexural behavior of the strengthened specimens. The flexural performance of the strengthened specimens generally improved as the tensile properties of the ECC increased. The maximum mid-span loads and corresponding displacements increased by 34%-171% and 33%-163%, respectively, compared to the control specimens. Furthermore, the flexural stiffness of the strengthened specimens was enhanced by a maximum of 63%. The flexural strength and energy dissipation capacity of the strengthened specimens increased with the reinforcement ratio of the ECC. The maximum flexural strength and energy dissipation capacity of ECC-strengthened specimens were 2.39 and 7.01 times higher than those of un-strengthened specimens, respectively. In addition, the results showed that the maximum bending moments of un-strengthened and strengthened specimens could be better predicted by the existing theoretical model.