Safety Of Buildings Research Articles

Calibration strategies for long-term strain forecasting in high-rise building columns

Concrete exhibits long-term time-dependent behavior due to creep and shrinkage that impacts the safety and serviceability of high-rise buildings. These rheological effects are difficult to predict due to their random nature, dependence on environmental conditions, and loading history. Current methods include the use of creep and shrinkage tests of structure-specific concrete samples to update compliance and shrinkage, and sophisticated numerical models for prediction of the long-term structural behavior. However, creep and shrinkage tests are time-consuming, and simulation requires reliable numerical models and often proprietary solvers that are not available to the structural health monitoring (SHM) practitioner. Further, uncertainty propagation in complex numerical models is rarely seen in the relevant literature. In contrast, data-driven prediction methods using SHM data and simplified analytical models have shown to be successful for prestressed concrete bridges. In this work, we investigate calibration strategies of creep and shrinkage models using SHM data toward data-driven forecasting of long-term time-dependent behavior of high-rise buildings. A calibration strategy is identified that enables significant and consistent improvement of forecasting of long-term time-dependent behavior. It is also shown that continuous calibration can provide good predictions at least 30 days ahead. First-order analytical uncertainty propagation formulas are also provided. The calibration strategies are evaluated on data from two residential high-rise buildings in Singapore. Recommendations to the SHM practitioners are also given.

Design and Management of a Spatial Database for Monitoring Building Comfort and Safety

As the impacts of climate change on urban environments and buildings become more and more prominent, building comfort and structural safety monitoring becomes crucial. However, efficiently storing and managing the multi-source monitoring data generated during the long-term monitoring process has been an urgent challenge. In order to solve the above problems, this paper designs and develops a spatial database management system for building comfort and structural safety monitoring based on standard database development tools. A conceptual model of a spatial database for building comfort and structural safety monitoring is proposed, and the entities, attributes, and connections in the model are discussed to transform the E-R conceptual model into a logical model supported by an object-relational spatial database management system. Based on this conceptual and logical model, a mainstream backend framework was adopted and combined with common database and programming language tools and BIM (Building Information Modeling) technology for development to establish a spatial database management system with data storage, management, analysis, and visualization functions. We designed building monitoring experiments and proved through the experiments that the database management system can stably store, analyze, and manage the monitoring data and visualize the display, with the advantages of a fast response speed and low error rate. The spatial database system improves the storage and management efficiency of building comfort and structural safety monitoring data, eliminates redundant data, and realizes comprehensive analysis and management of building comfort and structural safety monitoring data. It provides data support for building comfort and structural safety assessment, helps users analyze the formation mechanism and evolution law of the urban heat island effect, assesses the interrelationship between climate change and urban building morphology, and constructs an urban thermal environment that is more adaptable to climate change.

Experimental and numerical study on a high-rise building with transfer slab

To evaluate the seismic performance of a high-rise building with transfer slab, a scaled model with a ratio of 1:15 is fabricated and shake table tests are conducted to investigate the seismic damage of the scaled model, in which the frequent, fortification, rare, and extremely rare multidimensional seismic excitations for different design targets are considered. The experimental results are analyzed and discussed to compare and validate the numerical results, including peak acceleration and inter-story displacement response. Through the discussion of experimental and numerical results, a qualitative evaluation was conducted for the seismic performance of high-rise buildings with transfer slabs. Results show that the numerical results agree well with the experimental responses, which reveal that the design performance goals under different seismic excitations can be achieved. Note that the shear-wall structure above the transfer slab undergoes elastic-plastic behavior before the frame structure below the transfer slab, ensuring the safety of the bottom frame structure. The seismic performance of the prototype building was qualitatively evaluated under rare and extremely rare earthquakes, which provide reliable basis for structural safety of the high-rise building with transfer slab. The achievements also contribute to the design of high-rise buildings with transfer slab and ensure the safety of occupants and minimize damage in the event of earthquakes.

Experimental investigation on a FRCM bio-composite for sustainable retrofitting of masonry buildings

Strengthening masonry structures by using green and natural materials has received increasing attention. Natural fibers can be obtained from vegetables, animals or mineral sources and can be used to meet modern buildings safety standards and to reduce carbon dioxide emissions. This paper presents a novel method to strengthen masonry buildings through the application of a mortar coating reinforced with natural fibers made of a jute or a basalt grid. This class of materials is known as Fiber Reinforced Cementitious Matrix (FRCM). FRCM composites can produce an increment in the mechanical properties of masonry members and contribute to the thermal-acoustic insultation of the building envelope. The mortar coating is made of a hydraulic lime: to increase thermal properties this was admixed with short spelt fibers. Both matrix (lime mortar) and fibrous material were initially mechanically and thermally characterized. Laboratory tests have been carried out to study the bond characteristics between the FRCM composite and brickwork masonry. It was found the low mechanical properties of jute fibers are aggravated by a low FRCM-to-masonry bonding, making difficult to use this material for structural retrofit. On opposite, basalt fibers exhibit high mechanical properties and their use in conservation is surely promising and interesting.

Methods of assessing the seismic resistance of building structures and nuclear power plant structures in Lira-SAPR program

This article proposes a methodology for assessing seismic resistance and determining the reserve of seismic resistance, taking into account the interaction of the structure with the foundation for buildings and structures of power units, strength and deformation criterion of workability, etc. During verification calculation, three criteria of strength of workability, compiled according to the General principles of ensuring reliability and structural safety of buildings and structures, were considered. The seismic calculation was performed according to the linear-spectral theory of seismic resistance. In LIRA-SAPR program, considerationoftheinfluenceofthebaseisimplementedaccordingtoBuildingnorm DBN B.1.1-12-2014. Building Construction in seismic areas of Ukraine.
 The method of calculating the value of the ultimate seismic resistance of HCLPF and the method of constructing damage curves are proposed. To determine the integral parameter HCLPF, which characterizes the level of seismic resistance of this element, a calculation analysis of the seismic resistance of elements of operating nuclear power plants was carried out within the framework of the method of ultimate seismic resistance. The methodology and verification examples for determining the values of FS and HCLPF parameters for reinforced concrete structuresin LIRA-SAPR programare proposed.

A Deep Anomaly Detection System for IoT-Based Smart Buildings

In recent years, technological advancements in sensor, communication, and data storage technologies have led to the increasingly widespread use of smart devices in different types of buildings, such as residential homes, offices, and industrial installations. The main benefit of using these devices is the possibility of enhancing different crucial aspects of life within these buildings, including energy efficiency, safety, health, and occupant comfort. In particular, the fast progress in the field of the Internet of Things has yielded exponential growth in the number of connected smart devices and, consequently, increased the volume of data generated and exchanged. However, traditional Cloud-Computing platforms have exhibited limitations in their capacity to handle and process the continuous data exchange, leading to the rise of new computing paradigms, such as Edge Computing and Fog Computing. In this new complex scenario, advanced Artificial Intelligence and Machine Learning can play a key role in analyzing the generated data and predicting unexpected or anomalous events, allowing for quickly setting up effective responses against these unexpected events. To the best of our knowledge, current literature lacks Deep-Learning-based approaches specifically devised for guaranteeing safety in IoT-Based Smart Buildings. For this reason, we adopt an unsupervised neural architecture for detecting anomalies, such as faults, fires, theft attempts, and more, in such contexts. In more detail, in our proposal, data from a sensor network are processed by a Sparse U-Net neural model. The proposed approach is lightweight, making it suitable for deployment on the edge nodes of the network, and it does not require a pre-labeled training dataset. Experimental results conducted on a real-world case study demonstrate the effectiveness of the developed solution.

Prediction of the Deformation of Heritage Building Communities under the Integration of Attention Mechanisms and SBAS Technology

The protection of heritage building communities is of important historical significance, the occurrence of a landslide is related to the safety and stability of the heritage building, and ground monitoring and forecasting are the key steps for the early warning and timely restoration of the heritage building. This study utilizes remote sensing technology to monitor the ground of a cultural heritage building, and employs a Long Short-Term Memory (LSTM) network for prediction. Firstly, we conducted ground subsidence monitoring within a specific time series of the study area using heritage remote sensing images and SBAS-InSAR technology. Following the subsidence monitoring, and incorporating an attention mechanism, we effectively localized and extracted features of heritage building clusters within the region. This approach efficiently addresses the challenge of feature identification resulting from the dense distribution of buildings and the similarity between various objects. The results indicate that the maximum subsidence rate in the research area reached −60 mm/year, reached a maximum uplift rate of 45 mm/year, and that the maximum cumulative subsidence reached −65 mm. Secondly, for the multi-level, multi-scale, and class-specific objects in remote sensing images, the LSTM network enables adaptive contextual information during deep and shallow feature extraction. This allows for better contextual modeling and the correlation between predicted and actual results reaches a 0.95 correlation, demonstrating the accurate predictive performance of the LSTM network. In conclusion, both LSTM and SBAS technologies play a crucial role in decision-making for heritage buildings, facilitating effective early warning and disaster mitigation.

Effect of roof design on wind load of buildings through numerical simulation

When the wind blows against a building, the resulting force acting on the building at a particular elevation is called the wind load. Measuring and minimizing the wind load is crucial to ensure the safety of buildings. Therefore, the objective of this study is to investigate the effect of a buildings roof design on the wind load by evaluating and comparing the wind pressure differences p that different building models experience by leveraging Computational Fluid Dynamics (CFD) simulations. The 3D CAD (Computer-Aided Design) software SolidWorks was used to construct building models of identical dimensions with the exception of roofs harboring different shapes and angles. By exerting a wind velocity through flow simulation, flow trajectories and cut plot graphs of wind velocity and pressure surrounding the building models are generated. Wind pressure differences p for each situation were calculated and compared based on the CFD results. Wind tunnel experimentation with building models will also executed to test the computed data and prove its reliability and applicability. The data shows that, among all tested roof designs, the barrel-vaulted roof exhibits the minimum pressure difference (of 171.15 Pa) between the windward and the leeward surface and experiences the least wind load and resists strong wind most effectively. It reduces up to roughly 15% of wind load compared to the worst case tested. For symmetric triangular gable roof designs, the greater base angle leads to greater wind load. Overall, this study provides the theoretical basis and scientific evidence for the building designs of the next generation.

Application of Bayesian network and genetic algorithm in construction safety evaluation

Developing a safety evaluation model for construction is of utmost importance due to the increasing prevalence of safety issues on construction sites in a rapidly growing sector. Consequently, this research integrates a clonal genetic algorithm (CGA) and a Bayesian network (BN) into the current building information modelling technology for building construction to establish a comprehensive safety evaluation model for building construction. To develop a framework for assessing building safety, this study initially filters the factors impacting building safety through an advanced evolutionary algorithm. Subsequently, a BN is employed to understand the structure and parameters of the model. When compared with both a back-propagation neural network (BPNN) model and a genetic-algorithm-optimised neural network model, the CGA–BPNN model shows a network training error of approximately 0.09%. Additionally, the target error value is observed to be around 0.02%, and the genetic cross-over probability of the CGA–BPNN model amounts to 0.6629. These results indicate the small algorithm error and appropriate training time of the model, as well as higher accuracy. The CGA–BPNN model filters the evaluation indexes in the BN and assigns appropriate weights to assess accurately the safety status of the construction project.

Spatial-temporal simulation for hospital infection spread and outbreaks of Clostridioides difficile

Validated and curated datasets are essential for studying the spread and control of infectious diseases in hospital settings, requiring clinical information on patients’ evolution and their location. The literature shows that approaches based on Artificial Intelligence (AI) in the development of clinical-support systems have benefits that are increasingly recognized. However, there is a lack of available high-volume data, necessary for trusting such AI models. One effective method in this situation involves the simulation of realistic data. Existing simulators primarily focus on implementing compartmental epidemiological models and contact networks to validate epidemiological hypotheses. Nevertheless, other practical aspects such as the hospital building distribution, shifts or safety policies on infections has received minimal attention. In this paper, we propose a novel approach for a simulator of nosocomial infection spread, combining agent-based patient description, spatial-temporal constraints of the hospital settings, and microorganism behavior driven by epidemiological models. The predictive validity of the model was analyzed considering micro and macro-face validation, parameter calibration based on literature review, model alignment, and sensitive analysis with an expert. This simulation model is useful in monitoring infections and in the decision-making process in a hospital, by helping to detect spatial-temporal patterns and predict statistical data about the disease.

View from the CEO: The Institution in 2023 – a hive of activity

IStructE CEO, Yasmin Becker, looks back on a busy 2023 including the Building Safety Act, RAAC, and equality, diversity and inclusion.

Comprehensive factor analysis and risk quantification study of fall from height accidents

Working at heights poses frequent and significant risks, demanding scientific approaches for investigating fall-from-height (FFH) incidents and proposing preventive measures to enhance building safety. Nevertheless, ongoing research on analyzing the causal factors behind fall-from-height accidents lacks a comprehensive qualitative and quantitative assessment of the interplay between these factors. To bridge this gap, this study introduces an integrated risk analysis model. Utilizing incident reports and leveraging the multi-case rootedness theory, the model initially identifies influential elements. Subsequently, employing the Grey Decision Making Laboratory (Grey-DEMATEL) and Interpretive Structural Modeling (ISM) techniques, a hierarchical network is constructed, followed by the transformation of this hierarchical network model into a Bayesian Network (BN) model using GeNie2.0 software. Ultimately, the study was based on data from 420 accident cases and analyzed the causes and diagnosis of the accidents. The findings indicate that A5 (Low-security awareness) is the most significant factor contributing to falls from great heights and that the connection between the components is dynamic and non-linear rather than simply independent and linear. Furthermore, the study established a likelihood of occurrence of such incidents of up to 57 % and ranked the probability of occurrence of each contributing component in the case of a fall from height. This study presents a scientifically valid method for analyzing fall-from-height accidents. Experimental results confirm the model's applicability, empowering contractors to improve safety management by accessing precise risk information and prioritizing preventive measures against interrelated accidents. The model facilitates informed decision-making for contractors to effectively mitigate fall-from-height risks and establish a safer working environment.

Assessment of Safety of Masonry Buildings near Deep Excavations: Ultimate Limit States

It is a common practice to construct new buildings in the close vicinity of existing buildings. New buildings require deep excavations, which cause non-uniform displacement of the ground, causing a negative impact on the safety and technical conditions of adjacent buildings, including masonry buildings. The fundamental condition to verify structural safety is the knowledge of impacts and the load-bearing capacity of non-strengthened or strengthened structures. Safety is provided via strengthening the structure against deformations related to the ground displacement or by reducing non-uniform displacements of the building structure. This paper focuses on strengthening the ground and underground parts of masonry buildings. It also describes general requirements for providing safety of buildings according to the standard Eurokode 0 and the simplified method for protecting building structures with the use of steel tie rods. Based on the design methods for masonry structures specified in Eurocode 6 and the know-how of the authors in the field of protecting buildings in mining areas, the original method was proposed to determine the required area of reinforcement in the form of steel rods. Also, the original methods were introduced to verify ULS for inclined walls primarily under vertical load and shearing of pillars between openings. In addition to these analytical methods, this paper also illustrates methods for strengthening the ground and underground parts of masonry buildings. Presented in this paper, original solutions used to determine the strengthening of masonry structures and original models used to verify ULS for deflected walls primarily under vertical load can be directly employed in the design practice. The standard criteria were applied and the effects of building deflections, which are not specified in Eurocode 6, were considered.

Analysis of fire risk and fire prevention of architectural heritage: A case study of mount wutai in China

As precious historical and cultural heritages in China, ancient architecture belongs to non-renewable resources. However, in recent years, fires in ancient buildings occurred from time to time, causing irreparable losses to Chinas precious historical and cultural heritage. In order to explore the existing problems of fire safety in ancient buildings and better prevent fire accidents, this paper starts with an introduction of the structural characteristics of ancient buildings in China, and then, on the premise of combining the characteristics of geographical culture, architectural structure, and materials of Wutai Mountain temple group, the paper also analyzes the fire risk of ancient buildings. According to the practical work experience in fire protection of Mount Wutai, feasible and reasonable fire protection measures of ancient buildings are put forward, including the enhancement of fire resistance of building materials, the related equipment and system, and the safety management, so as to minimize the fire risk and fire loss and achieve the purpose of protecting gorgeous ancient building civilization.

Numerical simulation and safety distance analysis of slope instability of ionic rare earth tailings in different rainy seasons

A significant number of ionic rare earth tailings slopes were generated during the process of rare earth mining and the factor of safety of these slopes continued to decrease under the action of rainfall. This study focussed on a specific tailings slope located in Dayu County, Ganzhou City. Through the utilization of MatDEM numerical simulation software, the variations in infiltration distribution and destabilization evolution of the tailings slope between different seasons were comparatively examined. The results indicated that during the rainy season (May to June), increased rainfall led to increased rate of water infiltration, consequently reducing the stability of the slope and exacerbating landslide damage. Furthermore, the study provided analyses of safety distances under different seasons of rainfall, taking into account the geographical location of the tailings slope in Dayu County, Ganzhou City, and the results of the analyses provided theoretical foundation into ensuring the safety of buildings and residents downstream of the slope.

Study of outdoor rainwater drainage pollution in a hospital

Abstract The outdoor rainwater drainage pollution in a large general hospital poses considerable threats to the environment and our health. A systematic analysis method was summarized in the investigation practice. Results showed that the pipe network damage caused by uneven geological settlement was the main reason for the pollution of the rainwater pipe network in the hospital. Countermeasures such as settlement repair and geological foundation reinforcement, rainwater and sewage pipeline transformation, the repair of mixed connection of rainwater and sewage pipes and polluted water sources, drainage health safety in isolated areas, and emergency storage tanks were discussed. After implementing the measures, the NH3-N measured value was within 0.82 mg/L, and the average removal rate was 97.4%. The chemical oxygen demand (COD) concentration also decreased significantly with an average of 12 mg/L and the average removal rate was 91.8%. The results show that the reconstruction can effectively deal with the problem of outdoor rainwater drainage pollution in the hospital. The study has specific engineering reference significance for medical building drainage system's health and safety research.

Fire Safety for buildings and constructions - Performance based design approach and the parameters should be considered in Viet Nam

Performance based design is an approach that being supported in several countries for constructions design in general, and design of fire safety for buildings in particular. However, in the aspect of authority, to pursue this design approach it is needed to provide relevant regulations that replace to current prescriptives onces. By reviewing major features of performance based standards that are applied in some countries, this paper would like to figure out and suggest the parameters should be considered and clearified for establishing the regulations on performance based design for fire safety of building that correspond to the specific features of Viet Nam.

Fire safety for buildings and constructions – Performance based design approach and the parameters should be considered in Vietnam

Performance based design is an approach that being supported in several countries for constructions design in general, and design of fire safety for buildings in particular. However, in the aspect of authority, to pursue this design approach it is needed to provide relevant regulations that replace to current prescriptives onces. By reviewing major features of performance based standards that are applied in some countries, this paper would like to figure out and suggest the parameters should be considered and clearified for establishing the regulations on performance based design for fire safety of building that correspond to the specific features of Viet Nam.

Fire safety for buildings and constructions – Performance based design approach and the parameters should be considered in Vietnam

Performance based design is an approach that being supported in several countries for constructions design in general, and design of fire safety for buildings in particular. However, in the aspect of authority, to pursue this design approach it is needed to provide relevant regulations that replace to current prescriptives onces. By reviewing major features of performance based standards that are applied in some countries, this paper would like to figure out and suggest the parameters should be considered and clearified for establishing the regulations on performance based design for fire safety of building that correspond to the specific features of Viet Nam.

A Comparative Review of the Statutory Periodic Building Inspection Implementation in the Klang Valley Region, Malaysia and Hong Kong, China

Government response to building calamities using certain approaches depends on the types of building failures. Such approaches are the Periodic Building Inspection (PBI) in Malaysia and the Mandatory Building Inspection Scheme (MBIS) in Hong Kong. Both statutory requirements are meant to maintain the safety and structural integrity of buildings, and MBIS is selected for comparison with PBI because of the many parallelisms between the applications of both laws. Since it was made a statutory requirement in 1994, studies have found that PBI implementation by various local authorities in the Klang Valley region, Malaysiawas insufficient. Comparing both statutory requirements offer insight and understanding into the compliance issues and solutions, therefore, benefiting the PBI from the proposed improvements. To achieve the aforementioned goal, the following objectives are proposed: a) To compare both statutory periodic building inspections; b) To identify gaps and best practices in both statutory periodic building inspections; and c) To propose improvements for PBI implementation. This research involves data gathering and comparative reviews of prior studies on PBI and MBIS. The study's outcomes suggest significant similarities in the challenges faced during the implementation of both statutory periodic inspections. These challenges encompass unclear legal procedures, insufficient government participation, and weak enforcement. Building owners in both localities also encounter hurdles related to financial limitations, gaining consensus from residents, and selecting suitable engineers. Hong Kong's targeted inspection using a risk-based approach prioritycan be emulated by local authorities in Malaysia.Hong Kong's approach of allowing other qualified professionals like registered architects and building surveyors to perform initial visual inspections could also be applied in Malaysia. KPKT should consider providing financial support to low cost building owners, similar to the initiatives of the Hong Kong Housing Society (HKHS) and Urban Renewal Authority (URA). Local authorities and KPKT need to refine their service delivery through improved inter-departmental collaboration and heightened engagement with building owners. Revisions to Act 133, mirroring enforcement methods in Hong Kong, would be beneficial. Additionally, efforts should be made to raise public awareness about the significance of conducting PBI.