Building Elements Research Articles

Investigation of the Mechanical and Physical Properties of Structural Lightweight Concrete Produced with Expanded Clay Aggregate from Söğüt Region

The use of mild materials shows an increasing tendency in industrial areas. These materials are also preferred to reduce the unit weight of the building elements in the construction sector. Various light aggregates are used to produce light concrete with a lower density than normal concrete, and the properties of these light aggregates significantly affect the properties of the concrete. In this study, the use of expanded clay aggregate (ECA) produced in the Söğüt region in structural lightweight concrete was examined. Expanded clay, sand, and crushed stone aggregate were used as aggregates in concrete mixtures. The mixture granulometry was kept the same for each group. For this purpose, 60 samples were prepared for a total of 4 mixtures with different contents. Slump and unit volume weight tests were carried out on fresh concrete samples, and compressive, flexural, and splitting tensile strength tests were carried out on 7- and 28-day-hardened concrete samples. Some of the concrete mixture samples were subjected to tests after being kept in the curing pool for 7 days, and some for 28 days. As a result of the experiments, the unit weight and compressive strength values obtained from the samples produced with ECA as coarse and fine aggregate in order to achieve the highest strength target are 1413 kg/m³ and 30 MPa, respectively. The same values were found to be 1652 kg/m³ and 39 MPa in the samples produced with river sand as fine aggregate and ECA as coarse aggregate. In the samples produced using ECA as fine aggregate and crushed stone aggregate as coarse aggregate, these values were also found to be 1689 kg/m³ and 50 MPa.

3D printing earth: Local, circular material processing, fabrication methods, and Life Cycle Assessment

Additive manufacturing with earth is an emerging, though largely uncharacterized, approach to fabricating low embodied carbon structures. It is critical to establish methods for processing 3D printed, locally sourced earthen materials in different environments to validate large-scale earthen additive manufacturing as a tool to address a growing global need for housing and climate-resilient architecture. We present a set of reproducible design guidelines for sourcing, processing, and characterizing locally sourced earthen materials. Soil type, moisture and fiber content, particle size distribution, and unconfined compressive strength are determined. Additionally, novel bridging, cantilevering, and hydrostatic pressure (formwork) testing methods are developed to link design constraints for full-scale printed structures to material characteristics. Modular and conformally printed full-scale wall prototypes are printed with a 6-axis robotic system. A Life Cycle Assessment of the prototypical earth printing system is conducted, establishing a point of comparison to the climate impact of other construction systems, including rammed earth, concrete masonry units, and 3D printed mortar. We demonstrate that printing highly functional building elements with repeatable mechanical characteristics is possible using locally sourced earth mixtures. By illustrating a range of reproducible material and geometric possibilities, we expand the design space of additive earth and its applications.

Sound transmission loss of vertical building partitions designed to meet shear structural requirements

Vertical partitions often include structural building elements designed to meet shear requirements. Shear partitions are designed to resist lateral load due to wind or seismic activity and are required in many regions throughout North America. Nightingale et al. completed a 70-assembly series quantifying the effect of shear OSB on the sound transmission loss (STL) of both wood- and steel-framed single-stud assemblies in the National Research Council Canada (NRCC) research report NRCC-45018. This research study builds on the NRCC research with a test of over 200 wood and steel assembly partitions. This research study includes single-, staggered-, and double-stud framing as well as various forms of shear treatment such as OSB Plywood installed on one or both sides of the partition, attachment with various nail attachment patterns, and steel strapping. The effect of these partition elements on the STL will be presented and discussed. Additionally, the effect of sound isolation treatment, such as additional mass, resilient channels, resilient sound isolation clips, and constrained-layer damping will be presented and discussed.

A hybrid test method for measurement of airborne sound transmission loss of building partitions and elements

Single-number ratings, such as sound transmission class (STC), outdoor to indoor transmission class (OITC), and weighted sound reduction index (Rw), have been widely used to indicate the sound transmission properties of the building elements. The required transmission loss values over the frequency spectrum can be obtained from the two reverberation rooms test method (ASTM E90, ISO 10140), field measurement method (ASTM E966), or intensity method (ISO 15186). The limitations of the number of testing facilities that can provide the diffused field, minimum cut-off frequency, and other standard laboratory requirements, made the sound transmission loss measurement a costly and time-consuming procedure. In this study, alternative methods to measure the sound pressure and intensity have been investigated. The main objective of this research was to eliminate the complicated requirements of the diffused field and the room absorption measurement by averaging the direct sound amplitude at several angle of incidents and using the intensity probe to measure the sound intensity. In conclusion, the sound transmission loss, STC, and OITC values of double-glazed windows obtained from the hybrid method have been compared with predictions from the existing theory and the ASTM E90 standard test results.

Digital Marketing in the Age of Cyber Threats: A Comprehensive Guide to Cybersecurity Practices

As digital marketing strategies become increasingly integrated into business models, unique vulnerabilities to cyber threats make cybersecurity essential. This descriptive study provides a detailed analysis of cybersecurity for digital marketing, which is rapidly evolving with technological advancements and consumer behavior transitions. The integration of tools like Search Engine Optimization, social media, and online advertising and their susceptibility to cyber risks are investigated. Critical cybersecurity threats in digital marketing, including phishing attacks, malware and ransomware, data breaches, and Distributed Denial of Service attacks, are explored, emphasizing their potential impact on business operations, customer trust, and brand reputation. The study further explores best practices in cybersecurity tailored to the digital marketing area, advocating for regular software updates, comprehensive employee training, stringent data encryption protocols, strong password policies, multi-factor authentication, and periodic security audits, highlighting the importance of data backups and adherence to data protection laws in maintaining legal and ethical standards. The role of Artificial Intelligence and Machine Learning is investigated, emphasizing how these technologies enhance cybersecurity measures through proactive threat detection and efficient incident management. Additionally, the study examines the rising consumer concerns and awareness regarding data privacy and security in digital marketing, reflecting how these concerns influence business practices and the increasing demand for transparency and data control among consumers. Necessitating continuous vigilance and adaptation to protect against ever-evolving cyber threats, effective cybersecurity is indispensable in digital marketing for protection against cyber threats and as a vital element in building and maintaining consumer trust and loyalty.

Structures incorporating damping devices: Are we correct in our design thinking?

The use of discrete damping devices in New Zealand buildings is increasing as designers seek to limit damage to both architectural and structural building elements in moderate earthquakes. The overall damping of the structure becomes a combination of inherent material damping, hysteretic damping from yielding of building elements at specific locations and damping from discrete devices. For over 60 years, engineers have used simplified analysis procedures (e.g., modal response spectrum analysis) to predict building response under seismic actions. The design of structures incorporating viscous dampers requires a paradigm shift in approach as the force each damper resists is a function of the relative velocity between its ends. Popular pseudo-static design methodologies promote the use of a viscous strut in the analysis model to represent them. However, it is incorrect to use elastic, mode-based analysis for a structure incorporating damping devices and relying on significant inelastic behaviour. This paper elucidates the complex mechanics of damper-structure interaction by reviewing some of the established classical, modal‑based, simplified analysis techniques used in seismic design. A series of numerical investigations demonstrate how these techniques are usually invalid for structures that incorporate viscous dampers because they violate the laws of physics. The reason why mode-based techniques are invalid is explored with reference to the imaginary components of the natural modes of vibration and the effect on them of significant inelasticity within the structure. The dynamic characteristics of viscous dampers challenge conventional design approaches such as displacement-based design. This paper establishes that nonlinear time-history analysis is the only meaningful way of predicting the dynamic response of a structure incorporating viscous dampers when significant inelastic behaviour of the structure is expected.

Privacy preserved and decentralized thermal comfort prediction model for smart buildings using federated learning.

Thermal comfort is a crucial element of smart buildings that assists in improving, analyzing, and realizing intelligent structures. Energy consumption forecasts for such smart buildings are crucial owing to the intricate decision-making processes surrounding resource efficiency. Machine learning (ML) techniques are employed to estimate energy consumption. ML algorithms, however, require a large amount of data to be adequate. There may be privacy violations due to collecting this data. To tackle this problem, this study proposes a federated deep learning (FDL) architecture developed around a deep neural network (DNN) paradigm. The study employs the ASHRAE RP-884 standard dataset for experimentation and analysis, which is available to the general public. The data is normalized using the min-max normalization approach, and the Synthetic Minority Over-sampling Technique (SMOTE) is used to enhance the minority class's interpretation. The DNN model is trained separately on the dataset after obtaining modifications from two clients. Each client assesses the data greatly to reduce the over-fitting impact. The test result demonstrates the efficiency of the proposed FDL by reaching 82.40% accuracy while securing the data.

Study of the Effects of Natural And Man-Made Origin On the Technical Condition of Architectural Monuments

The results of research into the dynamic characteristics of technical objects under the influence of loads of natural and man-made origin are presented. The object of research is the phenomenon of propagation of vibrations in the load-bearing elements of construction structures. One of the problems in the inspection and monitoring of construction objects is the assessment of the dynamic action on the load-bearing elements of the structure. The external influence of dynamic phenomena of natural and man-made origin on the condition of the load-bearing structures of the Cathedral "Sophia of Kyiv" was studied. The revealed phenomena of the transmission of vibrations of the general system of the building made it possible to formulate the reasons for the appearance of defects. The obtained research results can be used in the development of numerical and experimental methods and algorithms for assessing the technical condition of load-bearing elements of buildings and structures under the action of dynamic loads of various sources.

SiN integrated photonic components in the visible to near-infrared spectral region.

Integrated photonics has emerged as one of the most promising platforms for quantum applications. The performances of quantum photonic integrated circuits (QPIC) necessitate a demanding optimization to achieve enhanced properties and tailored characteristics with more stringent requirements with respect to their classical counterparts. In this study, we report on the simulation, fabrication, and characterization of a series of fundamental components for photons manipulation in QPIC based on silicon nitride. These include crossing waveguides, multimode-interferometer-based integrated beam splitters (MMIs), asymmetric integrated Mach-Zehnder interferometers (MZIs) based on MMIs, and micro-ring resonators. Our investigation revolves primarily around the visible to near-infrared spectral region, as these integrated structures are meticulously designed and tailored for optimal operation within this wavelength range. By advancing the development of these elementary building blocks, we aim to pave the way for significant improvements in QPIC in a spectral region only little explored so far.

Modern Restoration Methods For Damaged Historical Buildings As A Result of Military Aggression. Case of Educational Institutions

As a result of the military operations taking place on the territory of Ukraine, thousands of buildings and structures have suffered significant damage and destruction. A substantial share of such buildings belongs to immovable cultural heritage sites, such as historical buildings of local and national significance; frequently, including educational institutions such as kindergartens, schools, lyceums etc. Damaged buildings are subject to restoration by repairing or strengthening their building structures, restoration, or conservation. There is a large number of repair materials and technologies for conducting restoration works, which are regulated by the requirements of DSTU B V.3.1-2:2016. However, while performing repair work on the structures of historical buildings, it is necessary to focus on the DSTU-NB B B.3.2-4 requirements. Among the most common types of damage to historical buildings caused by blast waves, splinters etc., are cracks in the masonry of wall structures and foundations; cracks in the joint of structures; knocking out fragments of masonry with damage to facing; damage to the elements of the floor and covering; systematic soaking of foundations etc. An essential aspect of restoring historical buildings is the maximum preservation of their historical and cultural significance with minimal interventions in the structure of structures and their appearance. The article considers modern methods of restoring the operational suitability of historical building elements, namely repair of cracks by injection and impregnation; strengthening the walls of buildings with the help of external reinforcement with carbon tapes and installation of high-strength rods in stone walls; restoration of stonework using special mixtures; strengthening of reinforced concrete and metal span elements with high-strength carbon fabrics, or lamellas (FRP); installation of waterproofing of walls subjected to systematic locking from the middle of the building.

Biospinning of hierarchical fibers for a self-sensing actuator

Artificial muscles, skin, and flexible electronics all benefit from smart actuators. However, developing actuators with high self-driving/sensing capabilities, as well as the real-time feedback function, remains a difficult issue. Herein, we reported a hierarchical fiber actuator with a desirable function. The fiber actuator was created by parallel wet-spinning sodium alginate (SA) and polypyrene (PPy)/graphene oxide (GO) (PPy/GO), which was then twisted to form a hierarchical structure. The constructed hierarchical fiber actuator demonstrated IR irradiation (150 W) and humidity responsiveness (90RH%), as well as a real-time feedback function, allowing autonomous and remote control in difficult situations. Meanwhile, such fiber has a synergistic response to both IR and humidity, which have a strong linear relationship (y = -0.150x + 0.004 and y = -0.217x + 0.007), and can be used for remote controllable fixed-point transportation in complex environments as well as real-time detection feedback in fixed-point environments. The hierarchical fibers are easily incorporated into a variety of actuators and detecting devices, including a breathing sensor and a self-sensing weightlifter. In the field of artificial muscle functions, hierarchical fibers have the potential to be a significant building element for next-generation actuators.

Structural and Technological Aspects of Conservation of Street Art on Buildings Damaged During the War

Using the example of graffiti created by famous artists on the walls of buildings and structures damaged during hostilities in Kyiv and its suburbs, the article analyzes and summarizes the factors influencing the lifespan of street artworks. Special conditions for dismantling graffiti and changing the exposure are considered. Examples of measures taken to preserve art objects are given. The study provides recommendations for additional protection of building structures, which are the basis of murals, taking into account their condition and degree of destruction. The authors provide photographic materials and results from some of the most common objects. Also provided are constructive schemes for strengthening the building elements or their fragments and options for technological solutions for protection, preservation and further dismantling. The article also includes materials from already implemented projects: applications of street art, which were saved using these other methods and techniques.

PETROARCHAEOLOGICAL STUDY OF MEDIEVAL RUINS OF BZOVÍK FORTIFIED MONASTERY

The article represents the results of the complex petroarcheological study focused on the building material with respect to the restoration of the old fortified monastery Bzovík (Central Slovakia). The aim of the study was to determine the original building material and to suggest the best solutions of the building recovery. The petroarcheological study enabled to describe the present state of the used rocks, their resistance and several types of mortars. The aim of the study was determining the material of building We found that the majority of the building stones are from the Neogene volcanics of the Štiavnica stratovolcano. Mainly effusive and extrusive activity of andesite volcanism. Distinguish the original and more new additional building elements, suggest suitable procedures and materials with respect to the sanitation of the building complex.

Quantum Molecular Devices.

Miniaturization has been the driving force in contemporary technologies. However, two main obstacles limit further progress: additional reduction in size has reached its quantum limit, and lithography has reached its threshold. Future progress requires tackling three challenges: chemical synthesis of a complete device, active cooling for exploiting quantum characteristics, and quantum coherent control for operation. Chemical synthesis replaces the current top-bottom approach to manufacturing with bottom-up synthesis from elementary building blocks. New ultracold synthetic methods should be developed. An additional challenge is the active cooling of molecules, where the bottleneck is entropy removal. Notably, the current solution, namely, diffusion, is too slow. A coherent approach offers a possible solution; specifically, quantum coherent control is the method of choice for manipulating ultracold matter. Finally, the many degrees of freedom of molecules should be an asset that allows the design and implementation of complex tasks such as sensing communication and computing.

Multiscale analysis of recycled coarse aggregate concrete under the synergistic action of KH560 and PVA fibers

Considering the long-term working performance of the waste concrete building elements, this study used 3-Glycidoxypropyltrimethoxysilane (KH560) and Polyvinyl alcohol (PVA) fibers to modify the recycled concrete (RC) with the aim of improving the mechanical and long-term properties of RC. In this study, the mechanical properties of recycled coarse aggregate (RCA) concrete before and after modification were systematically investigated. The macroscale results showed that KH560 compensates for the reduced compressive strength of RCA concrete due to PVA fibers. The synergistic effect of PVA and KH560 substantially increased the flexural and shear strength of RCA concrete, with a maximum increase of 22.6% in flexural strength when the RCA substitution rate was 80%. The results of three microscopic tests (SEM / FTIR/XRD) revealed that KH560 increased the content of cement gel, which then optimized the internal pore structure of RCA concrete. The chemical reaction between KH560 and cement produced SiKH560-OKH560-SiCSH. At the nano-scale, computational analysis methods in atomistic modeling techniques were employed to model PVA fibers, cement and KH560, and the dynamic and static simulation results of the model were combined to discover a consistent SiKH560-OKH560-SiCSH chemical bond between KH560/CSH and both old and new CSH, Additionally, the findings revealed the coexistence hydrogen and ionic bonds. KH560 improves the interaction between PVA fibers and cement by forming numerous hydrogen bonds, and resolves the weak interface between the new and old cement through stable chemical bonds.

High-rise building foundation design of the Lakhta Center

The foundation is the most significant element of buildings. The foundation structure closely relates to the general construction of the building frame and is largely determined by soil conditions. High-rise buildings are complex engineering structures with increased requirements for strength, stability and durability. Therefore, their safety and durability depend on strength, deformity and stability of foundation. These principles allow creating foundations of the higher quality, bearing capacity, reliability, and durability.Purpose: Optimization of production processes in the construction of foundation structures of super tall buildings and structures.Research findings: The structural design of the Lakhta Center 462 m high in Saint-Petersburg, which is the tallest building in Europe. A particular attention is paid to the design and construction of the foundation. Key results can prove operation and design of high-rise buildings designed for weak and unstable soils.Value: Determination of the most significant factors influencing the choice of production processes during the construction of super-tall buildings.

Technical State, Renovation Need and Performance of Renovation Solutions of Estonian Wooden Log Houses

The wooden log house serves as a prevalent architectural archetype in rural regions of several Nordic and Baltic countries. To ensure the long-lasting nature of these buildings, proper maintenance is imperative. However, in order to meet the evolving expectations of residents and minimize the environmental impact, a deep renovation is currently required. To successfully achieve the goals of this renovation wave and effectively address the personal needs of the homeowners, it is crucial to develop systemic renovation solutions that can be offered through a digital renovation passport. Consequently, the purpose of this study is to identify common damages, renovation requirements, and evaluate current renovation practices. The findings will serve as a crucial resource for the development of a digital renovation passport. In our study, we utilize rural wooden log houses (comprising 208 houses, 4 years of data) as our research subject. The building elements that are most in need of renovation are the external walls, roofs, and foundations, which require renovation in 77%, 63%, and 63% of the buildings, respectively. The primary cause of damage to the vulnerable structures is excessive moisture. Additionally, decay in the foundation can be attributed to factors such as erosion of mortar, frost, insufficient plinth height, inadequate foundation depth, and inadequate moisture protection. Recommendations provided by consultants primarily focus on restoring and preserving the dwellings' original architectural appearance. As a result, they are deemed insufficient in terms of improving energy performance and indoor climate. This lack of comprehensive consultation is concerning as it fails to consider the potential for cost efficiency, minimizing disruption to occupants, and achieving a comprehensive end result. The absence of recommendations for enhancing indoor climate, energy efficiency, general living quality, and reducing the building's carbon footprint performance the necessity for such renovation solutions and the importance of educating professionals and homeowners. The study's novelty lies in the establishment of statistical probabilities for damages and their causes, as well as the assessment of renovation and maintenance needs and the quality of existing recommendations. Results are scaled to the Estonian building stock, showing the renovation need on national scale. The findings can be incorporated into the digital renovation passport, along with specific renovation goals related to a given house.

Reinforcement of Traditional Wood-Frame Tabique Walls Using Wood-Based Panels

ABSTRACT In many regions of Portugal wooden-frame walls, known as tabique walls, are commonly found in old buildings. This type of wall is a traditional building element made of raw materials such as earth, wood and stone. These walls are generally used as non-structural elements (partitions) but are also used as structural solutions. Their maintenance in service must be based on the comprehension of their construction system and the materials involved, as well as sustainable reinforcement solutions. This study presents a reinforcement solution based on the application of wood-based panels (MDF and plywood) applied to their faces (sheathing). To assess this solution (reinforced and unreinforced), wall specimens were subjected to in-plane shear testing. The results showed a substantial increase in rigidity, even in cases where the reinforcement takes place after the wall has suffered some damage.

Modelling Prefabricated Construction Safety

Prefabricated construction is expanding and taking over traditional construction with more intervention of prefabricated building elements. Despite prefabricated construction reducing health and safety risks compared to conventional construction, there is still a risk that needs to be addressed. This article aims to investigate prefabricated construction safety through accident analysis. The accident data was retrieved through governmental resources and covered accident claims, safety costs, vulnerable occupations, and injuries (including type, cause, prior activity, and site of injury). Prefabricated construction safety is then simplistic and predictively modelled. The most common trend has been reported with graphical representation and relevant discussion. Furthermore, the trends are forecasted by using the ARIMA model (p, d, q) based on key performance parameters. The conclusion has been driven by the current status of prefabricated construction safety. This study is a pioneer in modelling prefabricated construction safety to enhance understanding of accidents and forecasting through optimization.

Incorporating Context into BIM-Derived Data—Leveraging Graph Neural Networks for Building Element Classification

The application of machine learning (ML) for the automatic classification of building elements is a powerful technique for ensuring information integrity in building information models (BIMs). Previous work has demonstrated the favorable performance of such models on classification tasks using geometric information. This research explores the hypothesis that incorporating contextual information into the ML models can improve classification accuracy. To test this, we created a graph data structure where each building element is represented as a node assigned with basic geometric information. The connections between the graph nodes (edges) represent the immediate neighbors of that node, capturing the contextual information expressed in the BIM model. We devised a process for extracting graphs from BIM files and used it to construct a graph dataset of over 42,000 building elements and used the data to train several types of ML models. We compared the classification results of models that rely only on geometry, to graph neural networks (GNNs) that leverage contextual information. This work demonstrates that graph-based models for building element classification generally outperform classic ML models. Furthermore, dividing the graphs that represent complete buildings into smaller subgraphs further improves classification accuracy. These results underscore the potential of leveraging contextual information via graphs for advancing ML capabilities in the BIM environment.