Vulnerable Elements Research Articles

EVALUATING THE PHYSICAL VULNERABILITY OF PUBLIC SCHOOL BUILDINGS AGAINST FLOODING IN METRO MANILA, PHILIPPINES

Vulnerability analysis has always been an integral part of disaster risk assessment. This study aims to assess the physical vulnerability of public school buildings against flooding. It discusses the vulnerable elements or attributes, the extent of damages incurred during flood events, the damage response, and the future steps that must be taken to increase flood resiliency. The study used empirical data collection using semi-structured interviews to characterize the common types of public schools and to collate the damage responses. Quantity surveying was performed to measure the amount of damages related to different flood depths. Structural damages to public school buildings are not expected for flood heights ranging from ground level up to ten (10) m. However, damages are incurred by building finishes and fixtures. Floors, walls, and septic system are cosmetically damaged. Vulnerable components include wooden elements like doors, cabinets, blackboards and ceiling, and electrical fixtures such as wiring, lighting, outlets, switches, and fire alarm system. Comprehensive vulnerability description of public school buildings were represented as curves of flood depth vs. damage index. The damage ratio decreases as the number of floors increase. Maximum damage to one-story building is 23.6% while at 15.02% for four-story school building. This study is an attempt to promote further research of the subject matter in developing countries towards flood resiliency in the built environment.

Numerical modeling of a majestic masonry structure: A comparison of advanced techniques

The present study aims to provide a comparative analysis between discontinuous models (DM) and continuous models (CM) for the analysis of majestic masonry structures subjected to seismic events. Specifically, the study models the ‘Santa Maria Annnuziata’ church damaged after the Central Italy earthquake sequence in 2016 and 2017 years. The DM is evaluated using different types of interaction laws between blocks: the Discrete Element Method (DEM) and the Non-Smooth Contact Dynamic method (NSCD). The nonlinearity of the material in the CM, instead, is considered using the Concrete Damage Plasticity model (CDP). To assess the models' effectiveness in identifying vulnerable elements, non-linear dynamic analysis is performed through the main earthquake events recorded nearby the church during the Central Italy earthquake. Following this, the models are subjected to the 7.8- magnitude earthquake that occurred in February 2023 in Turkey to observe the damage evolution under higher magnitude events. The primary objective of this study is to improve the understanding of the strengths and weaknesses of both models and their potential applications in the analysis of historic masonry structures.

Міжнародний досвід повоєнної відбудови житлового фонду та вирішення житлових проблем ВПО

The article analyses the international experience of solving the housing problems of forcibly displaced persons during the post-war recovery of the economy and socio-humanitarian space. The author characterises the role of the state in developing strategies, determining priorities, consolidating efforts, and institutionally ensuring the process of restoring living space, rebuilding housing and social infrastructure, as well as ensuring control over the use of funds, residential premises, and structures, the use of technologies and standards of construction and reconstruction. National priorities have been determined in the organisation of measures to provide housing for victims of hostilities and forced migrants, prioritisation of reconstruction, and new construction tasks. The necessity of accumulation and optimal use of internal resources, as well as the expediency of attracting foreign investments and the use of external financial assistance for the reconstruction of living space, industrial and social infrastructure with observance of systematicity and compliance with the trends of structural, technological and social development, are argued. The paper clarifies the mechanisms of interaction between the government and private investors, stimulation of entrepreneurial activity, encouragement and support of citizens in their actions regarding the independent restoration of housing, and arrangement of adjacent territories. It was found that the excessive bureaucratisation of assessing the damage caused and drawing up an application for assistance significantly slowed down the process of restoring damaged housing, which caused additional budget costs for providing IDPs with temporary housing. Ignoring the historical and cultural differences of the inhabitants of different territories and the accumulation of socially vulnerable and marginal elements led to an increase in social tension at the local level, and people affected by the war formed a permanent dependence on state aid. The need to consider positive and negative foreign experiences in the state management of the post-war reconstruction of the country’s housing stock is substantiated.

Implication of Applying IPCC AR4 and AR5 Framework for Drought-based Vulnerability and Risk Assessment in Bankura and Purulia Districts, West Bengal

In the districts of Purulia and Bankura, this study offers a methodology for spatial assessment of vulnerable and risk-prone areas. These districts are adjacent in space and have identical geographic characteristics (other than the eastern portion of Bankura district). Vulnerability and risk assessment could be used to measure the interactions between individuals and their surroundings. This research aims to pinpoint the areas in these two districts that are particularly susceptible to natural, social, and meteorological disasters. The natural and climate-induced factors considered are rainfall distribution and vegetation conditions. The social factors are agricultural dependence, percentage of farmers, female population, labor dependence on agriculture, and literacy rate. The potential impacts of developmental and environmental degradation processes can be examined and assessed by classifying regions according to their vulnerability and risk levels. The fundamental factors impacting susceptibility and risk, which are recognized, and the associated thematic-based outputs are produced in this study based on the persistent phenomenon of drought within these two districts. The elements of vulnerability selected for this study are exposure, sensitivity, and adaptive capacity (IPCC AR4) and risk, which is the combined outcome of hazard, exposure, and vulnerability (IPCC AR5). The aim of this research is to create a simplified, scalable assessment model for evaluating both vulnerabilities and threats, which can help with drought mitigation. It has been observed from the results that the western portion of the study area (Arsha, Purulia-I, Baghmundi blocks of Purulia district) with relatively higher risk and vulnerability needs more attention for reducing the vulnerability and risk than the eastern part. As a result, this research can serve as a platform for district-level prioritizing efforts, emergency response protocols, and policy interventions aimed at reducing disaster susceptibility (mostly drought) in Bankura and Purulia districts.

MECHANISMS OF IMPLEMENTATION OF THE POLICY OF SELECTIVE REGULATION OF COMMODITY MARKETS IN THE POST-WAR PERIOD

MECHANISMS OF IMPLEMENTATION OF THE POLICY OF SELECTIVE REGULATION OF COMMODITY MARKETS IN THE POST-WAR PERIOD

Rocking Analysis of Towers Subjected to Horizontal Forces

In seismic-prone areas, ecclesiastical masonry complexes have shown very high vulnerability, as detected after the last Italian earthquakes, such as those that occurred in L’Aquila (2009), Emilia-Romagna (2012), Central Italy (2016), and Ischia (2017). Partial collapses often affect these types of aggregate buildings due to the presence of highly vulnerable elements, such as bell towers. Preliminary analyses, including straightforward and quick methods, are necessary to assess their vulnerability. This paper proposes a simplified method to analyse bell tower dynamic behaviour and the results obtained are compared with several different approaches. The first is based on the dynamics of two rigid blocks (bell tower and lower building), and the second concerns a single block (bell tower only). The proposed method can be considered as a quick procedure involving few parameters to provide a preliminary analysis before use of more complex models such as finite element models. It aims to provide a valuable tool for the initial evaluation of the stability and risk index of the structure. The double-block model considers the associations between the rocking of the bell tower and the sliding motion of the underlying building. A parametric evaluation for different friction coefficients is proposed. The results are represented as rotation time histories and compared with analysis of the single vulnerable element, i.e., the bell tower subjected to the floor spectrum. The results show that high excitation frequency and friction coefficient values make the bell tower stable, and that the simplified model provides a clear safety advantage.

Playing Bayesian Stackelberg game model for optimizing the vulnerability level of security incident system in petrochemical plants

Constrained by the limited security resources of petrochemical plants, optimizing the vulnerability level of the security incident system plays a significant role in preventing and controlling security incidents. Previous research for security vulnerability has concentrated on the protection system, neglecting the influence of interconnections among vulnerability elements. The intelligence and struggle features of Security Incident System Vulnerability (SISV) elements are critical for optimizing the vulnerability level and characterizing the evolution of intelligence of security incident participants. By studying the game characteristics among SISV elements, this paper proposes the Bayesian Stackelberg SISV game model based on the security incident protection model established. In the game model, the strategies for protective vulnerability and aggressive vulnerability are defined as setting the security layer sub-units and the protective vulnerability levels, and setting the intrusion routes and the aggressive vulnerability levels, respectively. The model optimizes the security system vulnerability levels within the different security layer sub-units, based on the available security resources. Despite being demonstrated via an illustrative case, the defender's return on investment is significantly higher by using the SISV game model, the methodology can easily be tailored to a wide variety of petrochemical plants.

Seismic assessment of different vertical bracing systems in staging of elevated liquid retaining tank

The study of earthquakes indicates that earthquakes have a significant impact on the grid system, as well as significant catastrophic effects on human life, buildings, bridges and other structures. In macro scale water distribution network, water tanks play the key point site component, and it is the most vulnerable element in case of an earthquake. Water tanks play a vital role in our lives as they help to store and supply water for domestic and commercial purposes. They also store water for firefighting, irrigation and other agricultural needs. Based on the previous literatures, papers, articles, and other sources, it can be concluded that during an earthquake generally, a liquid retaining structure, i.e., water tank failure generally occurs due to the inability of the staging system to resist lateral movement. Most post-earthquake failures of elevated tanks are likely to result from dynamic buckling caused by overturning moments of seismically induced fluid inertia and surface sloshing waves. As they are the vital structures of our society, their construction and proper seismic evaluation is crucial. In this paper, the seismic response of liquid retaining tanks for different vertical bracing systems has been compared as per IS1893:2014 part-2 and the response spectrum analysis procedure. In all the models the storage tank's capacity has been taken as 150 cubic meters, keeping all the dimensions the same. The loads are considered as per IS875, IS3370 and other relevant codes. The different models considered in this paper are – water tank without bracing, water tank with diagonal bracing, water tank with cross bracing, water tank with K-type bracing, water tank with chevron bracing and water tank with box bracing. These models have been compared on the basis of different seismic parameters and optimized model is being suggested.

A Geo-Hazard Risk Assessment Technique for Analyzing Impacts of Surface Subsidence within Onyeama Mine, South East Nigeria

This paper proposes a geo-hazard risk assessment technique to analyze the impacts of surface subsidence monitored in a major coal mine in Nigeria. In many developing countries, disaster risk management schemes have mainly focused on traditional singular hazard assessment, vulnerability assessment, or risk assessment. However, it is difficult to use a singular application to adequately address hazard assessment due to the variation in data requirements, factors associated with the hazards, and the various elements at risk. Most times, hazard assessment schemes heavily rely on data and techniques from different global organizations that collate data on disasters, using various scales and objectives to make informed decisions. Several challenges seemingly arise from total reliance on these kinds of data due to standardization, the exact number of potential victims, and the purpose of the data collection. This makes disaster information collected at the local level unique and assessment schemes more complete; however, the coverage is limited worldwide. The proposed approach combines the spatial relationship between vulnerability assessment and elements at risk to highlight the grave consequences of potential disasters. Thus, the aim is to underscore the importance of integrating local-level inputs in analyzing risk factors and vulnerability indicators for hazard assessment. This study was conducted at the Onyeama coal mine in South East Nigeria. This area has experienced severe negative impacts of subsidence over the years. We exploit data from Sentinel-1 Synthetic Aperture Radar (SAR) Satellites and Small-Baseline Subset Differential Interferometric Synthetic Aperture Radar (SBAS-DInSAR) technique to map the study area. The results generate an elements-at-risk database with a particular focus on population density, road networks, and building networks identified as indices for loss estimation.

Dynamics of the Social Security Index in the Context of the Economic Crisis in Romania

In conditions of uncertainty, social protection issues are of paramount importance, and supporting measures are needed for the vulnerable population with an impact on social costs. Those costs have to be included in the state budget, and they generate budgetary imbalances that need to be counterbalanced by relevant budgetary policy measures. This paper proposes to develop, on the basis of state budgets and of demographic indicators, a social security index, whose dynamics will reflect the impact of the necessary measures in a period of economic and financial uncertainties. The key indicators used for calculating the social security index are composite financial risk, which is quantified using the budget’s dynamic expenditures, composite labour risk using employment stock, and unemployment and composite social risk using equilibrium between labour and retired labour. The paper studies the evolution of this index to identify inflection points that impact social security policy. We have dynamically identified the evolution clusters that differentiate the variability of the social security index over time, translated into the social security matrix proposed by the study for each composite index. The used methods in the study are empirical and analytical in nature, consisting of an econometric definition of the index structure and a dynamic analysis of the results obtained over the period 2010–2020. The results of the study will identify the financial risk diagram, which, based on the forecasted clusters of financial, social, and labour market risks, will create a useful picture for social policy makers that will highlight the current vulnerabilities of the three clusters from a social perspective. Last but not least, the presentation of the social security index is a valuable result for practitioners in their efforts to optimise social policies and increase socio-economic welfare. The results of this research will allow decision-makers to adjust their social policies on an informed basis in relation to the elements of vulnerability during periods of uncertainty, in comparison with the elements of stability identified during periods of economic growth.

A Strut-and-Tie Model for Predicting the Shear Strength of Exterior Beam–Column Joints Strengthened with Fiber-Reinforced Polymers

This paper presents a new strut-and-tie model (STM) based on provisions of ACI 318-19 and ACI 440.2R-17 for estimating the shear strength of fiber-reinforced polymer (FRP)-strengthened exterior joints. Beam–column joints are vulnerable elements in reinforced-concrete structures subjected to seismic loadings and similar extreme demands. The FRP strengthening technique offers numerous advantages for retrofitting joints in existing structures with inadequate reinforcement or confinement. The design of FRP-strengthened joints requires the development of reliable procedures, including equations to predict the shear strength of the joint. Existing literature and research on STM warrant the development of simple, reliable, and practical specifications applied to a wide range of design criteria. The proposed method involves an STM model containing horizontal and vertical mechanisms. The methodology compares predicted joint shear strength results with existing experimental results to obtain a reliable design approach. This comparison, along with verification of alternative analytical results, indicates the appropriateness of the presented model for predicting the shear strength of FRP-strengthened joints. Results contribute to the enhancement and efficiency of the practical design of these joints.

Assessing the Efficacy of Phenological Spectral Differences to Detect Invasive Alien Acacia dealbata Using Sentinel-2 Data in Southern Europe

Invasive alien plants are transforming the landscapes, threatening the most vulnerable elements of local biodiversity across the globe. The monitoring of invasive species is paramount for minimizing the impact on biodiversity. In this study, we aim to discriminate and identify the spatial extent of Acacia dealbata Link from other species using RGB-NIR Sentinel-2 data based on phenological spectral peak differences. Time series were processed using the Earth Engine platform and random forest importance was used to select the most suitable Sentinel-2 derived metrics. Thereafter, a random forest machine learning algorithm was trained to discriminate between A. dealbata and native species. A flowering period was detected in March and metrics based on the spectral difference between blooming and the pre flowering (January) or post flowering (May) months were highly suitable for A. dealbata discrimination. The best-fitted classification model shows an overall accuracy of 94%, including six Sentinel-2 derived metrics. We find that 55% of A. dealbata presences were widely widespread in patches replacing Pinus pinaster Ait. stands. This invasive alien species also creates continuous monospecific stands representing 33% of the presences. This approach demonstrates its value for detecting and mapping A. dealbata based on RGB-NIR bands and phenological peak differences between blooming and pre or post flowering months providing suitable information for an early detection of invasive species to improve sustainable forest management.

A method for rockfall risk quantification and optimal arrangement of protection structures along a road

The purpose of this study is to introduce a novel framework that aids in the installation of rockfall protection structures for the risk reduction of rockfall-related damage. In this study, we propose a computational method that performs risk analysis for a road and plans an optimal arrangement of rockfall protection structures. First, a rockfall trajectory simulation is performed using a three-dimensional numerical analysis method to obtain sufficient data for risk analysis. Then, the risk to motorized traffic during a certain period is quantified considering the relationship between rock block volume and rockfall frequency, the movement of rock blocks, the vulnerability of elements at risk, and some other factors. Finally, a knapsack problem that aims to minimize the total risk on a road while satisfying a budget constraint is solved. The proposed method is applied to an actual site and represents that it can derive a layout for protection structures to maximize the cost-benefit performance depending on the road traffic and budget conditions. The obtained results of the structural protection plan can be used to support road managers in decision making.

Perception of vulnerability to climate change in rural communities of cunduac�n, Tabasco: adaptation strategy

Climate change (CC) implies recent, rapid and more intense changes in climate. Its effects are reflected by the planet\'s natural processes and in human activities that impact socioeconomic and environmental systems. The research objective was to identify the perception of CC of the inhabitants of Cúlico 2nd Section, Huimango 1st Section and ejido La Chonita, through the Correspondence Analysis (CA) and vulnerability elements, estimating the criteria of Exposure (E), Sensitivity (S) and Adaptive Capacity (CA) that allows strengthening, through social participation, the capacities and values of the population. The study area is located near oil fields that generate environmental impacts, mainly on cocoa (Theobroma cacao) and corn (Zea mays) crops. A qualitative and quantitative analysis was carried out on a sample of 180 individuals. The results suggest that the population is exposed to the consequences of climatic events and degradation of natural resources, that there is sensitivity in their productive systems to diseases and in the quality of basic services, which limits the capacity for adequate response; it is important to generate actions to address local vulnerability, to strengthen the capacities and socio-environmental values of the population and to implement mitigation and adaptation actions, based on social participation and the formation of collaborative networks with other communities

Оценка надежности доильных установок на основании анализа их отказов

The milking and dairy equipment of a number of domestic enterprises is very worn out. The wear of milking equipment is caused by non-compliance with their maintenance and repair. To assess the reliability of individual elements and systems of milking machines used in production and to determine the ways to improve their operational characteristics, the authors analyzed the operation of enterprises located in the the Lyskovo district of the Nizhny Novgorod region using the most common linear milking machines. They analyzed failures and the time spent on ensuring the operability of milking systems. As a result of the study, the structure of failures for various systems and elements of milking machines was determined. The study determined the values of individual reliability indicators - operating time for failure and the failure fl ow parameter. The value of the availability coeffi cient, which characterizes both reliability and maintainability, was determined. The analysis of the reliability indicators of milking units showed that the largest number of failures of linear milking units falls on milking machines (41.2%), on the primary milk processing system (16.5%) and the vacuum system (11.3%). In the vacuum system, most of the failures are associated with the vacuum regulator (54.5%). In the dairy system, group counters are vulnerable elements. In milking machines, faulty teat cups account for 45% of failures, in which the nipple rubber wears out intensively. The lowest operating time for failure of milking machines and the dairy system indicates the need to improve their designs and the system of technical service. For elements of primary milk processing systems, the washing of milking equipment, and the vacuum system, the time required to eliminate failures is more than two hours, therefore, it is recommended to organize an exchange pool of spare parts and a modular repair method.

Seismic in-plane displacement capacity of masonry barrel vaults: the role of constructive aspects

Historic masonry vaults are one of the most vulnerable elements with respect to the seismic action. Cracks are often detected after post-earthquake surveys. However, it is difficult to directly link the observed damage to causes. Different mechanisms can occur during an earthquake, such as in-plane horizontal shear distortion or longitudinal opening/closing of the abutments. These mechanisms are not necessarily associated to a specific crack pattern, since other factors are involved in the determination of the detected crack status. Among these factors, constructive aspects (such as the brick pattern) play a major role. This study aims at investigating the possible correlation between constructive aspects and the crack pattern in barrel vaults subjected to in-plane shear mechanism. Numerical simulations are carried out on an ideal circular vault with a rectangular base of dimensions 3.1 × 5.3 m, and rise of 1.175 m. Three brick patterns are considered: radial, diagonal and vertical. In order to investigate these aspects, a micro-modelling numerical approach has been adopted. Results are presented in terms of ultimate displacement capacity, collapse mechanisms and crack pattern charts.

Effects of earthquakes with different nature on the seismic performance of masonry vaults

Past seismic events showed that earthquakes can cause severe damages in masonry vaulted structures, which can lead to significant damage, including fatalities, and heritage and economic losses. Although seismic guidelines suggest the implementation of specific modern strengthening techniques to prevent those seismic losses, many masonry vaulted structures are unreinforced and they are one of the most vulnerable structural elements in monumental buildings, such as churches and palaces. Thus, the present paper focuses on the seismic performance of a numerical model, which simulates an experimental reduced-scale dry-joints vault, through the nonlinear dynamic analysis, by applying several earthquakes of different nature. The numerical model was built based on the discrete element method, where it is possible to simulate the detailed geometrical properties: the interlocking between the blocks, the cuts along the diagonals, the offset of the units and the boundary conditions. Moreover, the model was calibrated based on results obtained from shake table tests. The results of this sensitivity analysis, obtained from the different inputs, are compared in terms of damage patterns.

Matriz analítica de vulnerabilidade da população adulta para Covid-19: uma revisão integrativa

Abstract Objective: To synthesize the elements of vulnerability to Covid-19 among the adult population. Method: Integrative review carried out between August and November 2020, with defined criteria of inclusion, exclusion and retrieving of studies. Data were extracted and synthesized by means of the categorical thematic analysis, and systematized by the vulnerability concept. Most relevant results: From 2247 articles retrieved, 70 original studies were selected, fully read and assessed. Four vulnerability markers emerged: Chronic Health Conditions; Daily Life Experiences; Social Insertion; and Health Services and Actions. Main conclusions: The identified vulnerability markers may support health professionals in the identification of patients with less autonomy and resources for self-care and protection against Covid-19. They may also foster the adoption of health and intersectoral interventions to protect patients against Covid-19, as well as the reduction of SARS-Cov-2 transmission rates within communities and other settings, with significant decline in the impact of the virus on society.

The use of a hydraulic electronic model to assess the functioning of the water supply network

Reliability and safety of centralized water supply are fundamental requirements for these systems — the most important component of public health and one of the key priorities of the state’s social policy. The development of water management and engineering infrastructure in Russian cities should be carried out under the draft schemes of water supply and sanitation. The water supply network is one of the most expensive and vulnerable elements of the city’s water supply system. A significant amount of statistical and operational information, the complex configuration and structure of urban water supply systems, and the uncertainty of water demand required the use of information technologies to survey the functioning of the city’s water supply network. The article presents their implementation based on the use of a hydraulic electronic model of a water supply network.

Diverse analysis method and its application to identify vulnerabilities of emergency protection of sodium generation boilers

The paper considers the possibility of assessing the development of accidents on the basis of a system-functional approach applied to the analysis of the probability of accidents in soda recovery boilers (SRBs). The main attention is paid to identifying the most vulnerable elements of the SRB and the possibility of diagnosing and preventing accidents based on the development of diagnostic systems in the existing APCS systems of the most important section of the SRB - the black liquor combustion system.