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The main objective of this paper is to assess the vulnerability of reinforced concrete (RC) educational buildings in Dhaka city to seismic activity by utilizing machine learning (ML) algorithms. There are three main stages in traditional seismic vulnerability assessment: rapid visual assessment (RVA), preliminary engineering assessment (PEA), and detailed engineering assessment (DEA). The conventional three‐step evaluation process for determining the seismic vulnerability of existing buildings is time‐consuming and expensive, especially when dealing with a large building stock or a city. This study focuses on using an ML‐based approach to evaluate seismic vulnerability, specifically in terms of the story shear ratio (SSR), which serves as the risk index. The main concept is the utilization of RVA data to obtain analytical results (SSR). The dataset utilized in this study comprises RVA data for 268 buildings and corresponding PEA data for the same 268 buildings. The RVA data include the construction year, condition, typical floor area, number of stories, total floor area, additions, alterations, redundancy, pounding, and irregularities. The PEA data comprise SSR, which was generated from linear dynamic analysis. These data were collected from the Urban Resilience Project of Rajdhani Unnayan Kartripakkha (RAJUK), which is the development authority of Dhaka. Random forest regression (RFR), support vector regression (SVR), and artificial neural networks (ANNs) are employed to determine the SSR of existing educational RC buildings. A comparative analysis for each model is also made. From the analysis results, it shows that RFR, ANN, and SVR achieved coefficient of determination (R2) of 20%, 25%, and 35%, respectively. Based on the findings from the three separate model analyses, it can be concluded that SVR produced the highest performance among the considered models. [ABSTRACT FROM AUTHOR]

Open ground story (OGS) buildings, prevalent in urban areas of countries like India, are structurally unique due to the absence of infill walls in the ground floor. This characteristic increases their seismic vulnerability. Traditional design practices often neglect the stiffness contribution of upper-story infill walls, leading to inadequate ground floor column design, which cannot withstand the amplified bending moments and shear forces during an earthquake. This study identifies the most vulnerable story in OGS buildings through a comprehensive seismic fragility analysis. The findings from the probabilistic seismic demand model (PSDM) log-log graph reveal that the ground floor is the most vulnerable, exhibiting significantly higher inter-story drift (ID), compared to upper levels, due to its reduced lateral stiffness from the absence of infill walls. ID, used as the demand variable in a power law model, captures this vulnerability, providing critical insights into the ground floor's heightened risk during seismic events. [ABSTRACT FROM AUTHOR]

Seismic retrofitting solutions for reinforced concrete (RC) school building types in high-seismic regions are extensively reported in the state-of-the-art. Conversely, limited studies have focused on the extent of retrofitting needed for RC school buildings in low- to moderate-seismic regions. To explore this aspect, seismic retrofitting options for RC school buildings in Sri Lanka are investigated. Three retrofitting options are examined: (1) adding/altering masonry infill walls (MI walls) to reduce irregularity in buildings, (2) RC jacketing of columns and (3) a combination of adding/altering MI walls and RC jacketing. These retrofit options are applied to a common typology of Sri Lankan MI-RC school buildings, considering two and three storey height variations. A simplified numerical modelling approach that accounts for the contribution of MIs, the shear failure of RC column and torsional effects is adopted to analyse the performance of the school buildings with and without retrofit. Based on the analyses, three damage states are defined: damage limitation (DL), significant damage (SD) and near collapse (NC). Finally, a multi-criteria decision making (MCDM) method is used to determine the optimal retrofitting option for the considered school building typology, considering engineering and economic parameters. The optimal retrofit solution for the three-storey MI-RC school building is found to be jacketing of ground floor columns. Conversely, for the two-storey MI-RC school building, alteration of infill walls (MI walls) is deemed optimal. Finally, a sensitivity analysis is carried out on the MCDM method. [ABSTRACT FROM AUTHOR]

Evaluating the seismic vulnerability of facades of historic masonry buildings is essential not only for their significant historical and heritage value, but also to evaluate the safety of this type of construction. This work applies a simplified methodology to assess the seismic vulnerability of the facade of masonry buildings in the historic center of Morelia, Michoacán, México. The historic center of Morelia was declared a World Cultural Heritage Site by UNESCO in 1991. On the facades, there is ornamentation with sculptural and vegetal decorative elements. The methodology involved conducting visual inspections to identify the location, type of structure, construction materials, doors, windows, balconies, cornices, ironwork, pediments, niches, and sculptures, among other characteristic elements of colonial architecture. The seismic demands were determined specifically for the city's historic center based on a recent seismic hazard assessment of Morelia. Based on the methodology and the compiled database, characterized vulnerability indices were defined for the different damage scenarios that buildings may present. Results indicate that earthquakes with intensities greater than VIII on the Modified Mercalli scale risk collapsing heritage masonry buildings' facades. [ABSTRACT FROM AUTHOR]

This research presents an interdisciplinary study on the impact of planning policies on the seismic vulnerability of historic areas, encompassing architecture, urban planning, and engineering aspects. It examines the spatial and temporal dynamics of urbanization and population growth, which alter cities' seismic exposure and vulnerability over time. Urban and engineering research methods are used to assess the seismic vulnerability variability in Yungay Quarter, a historic district west of downtown Santiago, Chile, with buildings constructed between 1839 and 2022. The study begins with a thorough review of Chilean urban planning policies and building regulations, combined with a detailed survey of the construction features in the historical neighborhood to classify building types. Next, the macro-seismic method is applied to a representative sample of 484 buildings to calculate vulnerability indices for unreinforced masonry and reinforced concrete structures, which are then used to estimate damage distributions. Seismic fragility curves for each building class are derived based on peak ground acceleration. These fragility curves are incorporated into risk assessments for potential ruptures along the San Ramon, Santiago splay and a deep intra-slab splay fault. The resulting risk scenarios can guide future urban planning policies and processes affecting this historical urban center. The innovations introduced by this work include a summary of how changes and updates to planning policies have influenced construction practices in the Yungay Quarter from 1839 to 2022 and the translation of these urban changes into variations in building fragility functions, enabling a comprehensive assessment of the potential impacts on these buildings from various potential. [ABSTRACT FROM AUTHOR]

Traditional ancient Tibetan buildings (TATBs) date back hundreds of years. The seismic performance of TATBs constructed with stones and mud was analyzed by utilizing structural subscale features (materials, walls, and structures). The key to load-bearing in TATBs is the three-leaf stone wall. Based on the mechanical properties of materials, compression tests and quasistatic static tests of walls, this paper confirms that the seismic resistance capacity of the three-leaf stone wall of TATBs is unable to meet Chinese standards. The aims of this study are to present the dynamic behavior of TATBs by shaking table tests. According to the experimental data, the transcendence intensity magnification calculation method is modified to calculate the seismic vulnerability of TATBs. The results show that when the peak acceleration of ground motion is 1.042 m/s2, 1.598 m/s2 and 2.881 m/s2, TATBs undergo slight damage, moderate damage, and severe damage, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Assessing the seismic vulnerability of existing buildings at the territorial scale is a crucial aspect for seismic-prone regions to properly plan effective strategies for disaster risk management. This paper presents a simplified methodology for the seismic vulnerability assessment of existing masonry and reinforced concrete buildings. The main purpose is to provide a tool able to evaluate the vulnerability of large building stocks, with the aim of defining priorities for further investigations or interventions. The procedure, inspired by methods in the literature devoted to the large-scale evaluation of structural vulnerability, allows defining the collapse peak ground acceleration (PGAc) through the evaluation of the resisting shear force, the latter being estimated by mechanical considerations and by taking expert judgment into account to consider the real structural complexities involved. A classification is proposed, which aims to categorize buildings within homogenous groups characterized by a level of seismic vulnerability belonging to given intervals. The method was calibrated with reference to several case studies in order to reach a sufficient level of reliability in the vulnerability estimate and was then applied to a significant number of school buildings in the province of Ravenna, Italy. For some of them, the simplified methodology was validated through comparisons with results obtained by means of vulnerability assessment procedures based on finite element analyses. [ABSTRACT FROM AUTHOR]

Masonry towers are peculiar structures with complex structural behavior despite biased conclusions deriving from their geometrical regularity and simplicity. Their geometrical features and the epistemic uncertainty that masonry material bears strongly influence their static and seismic behavior. This paper investigates a remarkable and representative case study. The bell tower of Portogruaro (Italy) is a 57 m high tall construction, built in the XII-th century, and has a notable inclination. The Italian Guideline for the safety assessment of masonry towers is a key focus in this paper, highlighting the pros and cons of different suggested approaches. Some relevant proposals are presented in this paper in order to address the seismic safety assessment of masonry bell towers. The findings show that very slender structures do not meet the guidelines recommendations due to limitations in their current stress state. In addition, in similar cases, the recommended values for the mechanical properties of masonry material led to predicting non-withstanding structural behavior, questioning the correct choice of the adapted material properties. Advanced pushover analysis has been conducted in order to investigate the results of the simplified approach in terms of failure patterns and seismic safety estimation. The simulations are implemented for four different hypothetical scenarios of the existing masonry mechanical properties. The results obtained for the case study tower reflect a different perspective in the seismic assessment of masonry towers when specific approaches are defined. The preliminary results on the safety of Portogruaro Tower show a significant variability of seismic safety based on the adopted scenario, highlighting the necessity to pay attention to the preservation state of the present case and of similar ones. [ABSTRACT FROM AUTHOR]

This research integrates physical, social, and economic aspects to address seismic vulnerability in the municipality of Toluca, Mexico. The objective is to design and implement a procedure that estimates seismic vulnerability at the urban block scale. The developed method combines physical and socio-economic dimensions to assess seismic vulnerability. The physical dimension includes susceptibility to seismic resonance, as well as the age and type of constructions, while the socio-economic dimension is based on the marginalization index. Mapping covers 7,807 urban blocks where five levels of vulnerability are identified, with 46.6% exhibiting severe and very severe levels. The resulting zoning is a robust tool for risk reduction, particularly for justifying the implementation of actions aimed at reducing vulnerability.

High-damping rubber bearings play an essential role in isolated bridges. They can prolong the natural vibration period of a bridge and reduce its seismic response. In order to quantitatively study the isolation performance of high-damping rubber bearings, this paper investigates a concrete-filled steel tube-tied arch bridge as the research object and uses symmetrically arranged high-damping rubber bearings for isolation reconstruction. Nonlinear finite element analysis models for isolated and non-isolated bridges are built based on the structural properties of the actual bridge. Based on the structural deformation failure criterion, a bridge damage evaluation index system is established, the damage index of each component is defined, and a quantitative analysis of different damage states is carried out. Based on the incremental dynamic analysis method, the seismic vulnerability curves of bridge components and systems are established. By comparing the seismic vulnerability curves of the bridge before and after isolation, the isolation effect of the high-damping rubber bearings is quantitatively evaluated. The results of the analysis show that the high-damping rubber bearings have a significant isolation effect on the bridge structure and the effect is symmetrically distributed along the longitudinal symmetry plane of the bridge. After adopting the isolation measures, the exceedance probability of damage of each component of the bridge is reduced to varying degrees. Among them, the isolation effect on piers and arch ribs is the most significant, up to more than 90%. At the same time, the exceedance probability of damage of the bearing itself is less reduced. This result is also consistent with the original intention of the design of the isolation bearing; that is, through the energy dissipation of the isolation bearing, the seismic response of other components of the bridge is reduced. [ABSTRACT FROM AUTHOR]

This study assessed the vulnerability of groundwater resources to the failure of the urban fuel distribution network under an earthquake. A case study of the Tehran, Iran, gas distribution network and the Tehran–Karaj Plain aquifer was conducted. To assess the seismic vulnerability of buried fuel pipelines in Tehran based on the fuel distribution network components, three possible earthquake scenarios were studied. To assess damage to the pipeline, a comprehensive model was developed using machine learning (ML). This model can assess and predict damage to a fuel pipeline and its type (i.e., leakage or full breakage). Moreover, aquifer contamination was assessed using the DRASTIC model. It was found that the ML-based pipeline seismic vulnerability assessment model had good performance in predicting seismic damage to the fuel distribution network, with a RMS error (RMSE) and a correlation coefficient (R) of 0.004 and 0.99, respectively. The results showed that the presented model had an acceptable efficiency in assessing the probability of seismic vulnerability of the buried pipeline and analyzing the pollution of the aquifer based on different earthquake scenarios. The developed groundwater seismic vulnerability assessment model can be used for further analysis in future research. Practical Applications: Earthquakes are one of the most important natural disasters, and have caused widespread financial, human, and environmental losses in different regions of the world, especially in seismic areas. The existence of faults and the possible deterioration of buried pipes makes earthquake crisis and its serious damage to humans and the environment more severe. One of the most important threats in this situation is the contamination of underground water with hydrocarbon substances due to leakage from the fuel transmission network. In this research, to evaluate the pollution of the aquifer due to the damage to the fuel transmission network, we developed a model using the machine learning method to analyze the vulnerability of the buried pipeline. The DRASTIC model also was used to evaluate aquifer pollution. To evaluate the presented model, the fuel transmission network and aquifer of Tehran, Iran, were studied. The results indicated acceptable performance of the proposed model for assessing the seismic vulnerability of groundwater. The presented model can be used for other areas. [ABSTRACT FROM AUTHOR]

This article presents the derivation of a fragility model for the Italian masonry school building asset, comprising 265 sets of fragility curves for as many building types, classified on the basis of few parameters: construction age, number of stories, plan area, and type of masonry (i.e. with regular or irregular pattern). The fragility assessment was carried out by means of parametric analyses, generating more than 7500 samples which were then analyzed through the mechanics-based procedure Vulnus. Sample fragilities were then linearly combined to obtain fragility curves consistent with the adopted taxonomy based on few parameters. A macroseismic–heuristic model from the literature was used to extend the fragility model to five damage states, according to the European Macroseismic Scale (EMS98). The proposed model was compared to empirical information in terms of observed damage on three existing schools and fragility curves recently derived by processing data of school damaged by the 2009 L'Aquila earthquake, showing a satisfactory agreement. In addition, a comparison with fragility sets for residential buildings was carried out. Both fragility models were developed with the same procedure, so as to point out differences between schools and ordinary buildings. Similar fragilities were observed for schools and residential buildings built before 1945, whereas for later periods, schools showed a higher fragility than the residential asset. Finally, seismic damage maps were developed at national scale showing the distribution of expected damage as a possible application of the derived model. [ABSTRACT FROM AUTHOR]

This study aimed to conduct a finite element analysis-based seismic evaluation of an existing reinforced concrete (RC) building for a high seismic zone in northeast India. The building model was evaluated for demands using response spectrum analysis (RSA) per the latest Indian standards. Data on the condition of existing material strength, geometry, and initial design are collected on site. Here, a procedure has been introduced to evaluate the seismic demand and capacity of structural members, for prioritizing strengthening work. The focus of the study was on assessing the potential failure of columns, with an aim to evaluate a building's susceptibility to failure and collapse. This evaluation procedure was applied to an existing low-rise RC building in northeastern India that was originally designed for gravity loads. The building had significant plan irregularities and stiffness irregularities. As anticipated, it was observed that the building did not withstand seismic design action, and all the columns failed, while the beams failed partially. For various load combinations, the demand–capacity ratio, particularly in terms of axial load and biaxial bending moments of the columns, emerged as a critical force-based factor in evaluating the building's safety under combined forces. The obtained results were validated on site by visual inspection of structural longitudinal cracks under high combined (axial with biaxial moment) demand in columns. The case study identified the six most critical columns that might lead to building collapse and need immediate strengthening. This approach demonstrated its feasibility as a tool for assessing the seismic performance of existing low-rise RC buildings for prioritizing structural strengthening work. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the elements at risk, through the identification of the main hazards, level of exposure and different dimensions of the vulnerability of the communities, is an essential step toward the definition and adoption of more effective risk reduction strategies. Historic urban centres have received special attention in the assessment of damage and physical vulnerability to earthquakes, but it is well known that vulnerability also depends on the social and demographic characteristics of communities. This paper discusses the application of a holistic approach aimed at assessing the seismic vulnerability of historic urban centres by considering their physical and social dimensions. Two index-based methodologies are presented, and the data are analyzed using the CENSUS block as the unit of study, which is scarcely present in the literature. The results of both indices are crossed through a matrix, which allows the classification of the blocks in five levels of priority and are mapped using a Geographic Information System tool. The Historic city centre of La Serena, one of the oldest in Chile, was selected as a case study. This historic city centre still preserves historic buildings of raw earth of diverse architectural typologies widely distributed throughout the country, which makes it relevant, not only by itself but as a model that can be replicated and extrapolated to other historic centres of similar constructive characteristics. [ABSTRACT FROM AUTHOR]

This research integrates physical, social, and economic aspects to address seismic vulnerability in the municipality of Toluca, Mexico. The objective is to design and implement a procedure that estimates seismic vulnerability at the urban block scale. The developed method combines physical and socio-economic dimensions to assess seismic vulnerability. The physical dimension includes susceptibility to seismic resonance, as well as the age and type of constructions, while the socio-economic dimension is based on the marginalization index. Mapping covers 7,807 urban blocks where five levels of vulnerability are identified, with 46.6% exhibiting severe and very severe levels. The resulting zoning is a robust tool for risk reduction, particularly for justifying the implementation of actions aimed at reducing vulnerability. [ABSTRACT FROM AUTHOR]

Schools In Algeria, built in the XIXth and XXth centuries, are not only places of education and learning, but make up a rich cultural heritage of architectural techniques and traditional know-how. However, their seismic vulnerability risks the safety of their occupants. They were built of masonry before seismic regulations were put into place, which increases their sensitivity to seismic hazard. Algeria is situated in a well-known zone of high seismic activity and the risk to these buildings challenges their structural behaviour. This study focuses on an assessment of seismic vulnerability on a specimen built entirely in hollow brick which wonderfully represents this architectural heritage leading to a better understanding of the potential risks for these buildings, at a structural level. Macro element models, using the Tremuri software, are subjected to a non-linear "Pushover" analysis in order to determine the degree of vulnerability and locate the weak sections of the structure which could collapse during seismic action. This study aims to highlight the seismic risks of these types of structures and also offer appropriate guidelines and recommendations that could be of use during a possible rehabilitation or conservation program of this built heritage site. [ABSTRACT FROM AUTHOR]

The prevalence of elevated reinforced concrete tanks is widespread across Italian water distribution networks, particularly in flat or low-relief areas. Primarily constructed by the late 1970s, these tanks often suffer from outdated hydraulic efficiency, unable to cope with the increasing urban water demands. With rising construction costs, the economic advantage has shifted toward underground tanks, leading to the decommissioning of many elevated tanks. Despite being obsolete, elevated tanks from the 1960s and 1970s still stand in densely urbanized regions. However, demolishing them may prove less cost-effective than retrofitting to restore their original structural capacity. The widespread presence of these structures, coupled with their susceptibility to decay from weathering and poor maintenance, necessitates a comprehensive assessment of their resilience against gravitational and lateral forces, including seismic activity. Consequently, there is a pressing need to develop an analysis and verification methodology, particularly focused on seismic resilience, tailored to existing elevated tanks. These structures, distinct from conventional reinforced concrete frames, are primarily designed to withstand vertical forces, emphasizing the importance of optimizing material usage in their retrofitting efforts. [ABSTRACT FROM AUTHOR]

This study highlights the continued need for numerical simulation methods to predict the earthquake response and damage of masonry mosques, despite recent advances in research. The Kamanlı Masonry Mosque in İzmir, Turkey was selected as a case study for this purpose. A probabilistic seismic hazard analysis was conducted using a uniform Poisson process model with 50-year probabilities of 2%, 10%, and 50%. Earthquakes from seismic sources were excluded based on time and distance, and the annual recurrence relationships of the source areas were determined using the least squares method. The non-linear response of a masonry mosque was investigated using the discrete element approach to study the impact of site conditions on its structural performance. Nonlinear dynamic analyses were conducted using records representing seismic events with 475- and 72-year return periods. The results indicated that the mosque is highly vulnerable to earthquakes, as the 475-year records resulted in significant damage and partial collapse. Damage indicators were employed to assess the response to the 72-year records, highlighting the most vulnerable areas that should be prioritized in any restoration efforts. [ABSTRACT FROM AUTHOR]

Seismic vulnerability assessment is one of the most impactful engineering challenges faced by modern societies. Thus, authorities require a reliable tool that has the potential to rank given structures according to their seismic vulnerability. Various countries and organizations over the past decades have developed Rapid Visual Screening (RVS) tools aiming to efficiently estimate vulnerability indices. In general, RVS tools employ a set of structural features and their associated weights to obtain a vulnerability index, which can be used for ranking. In this paper, Machine Learning (ML) models are implemented within this framework. The proposed formulation is used to train binary classifiers in conjunction with ad hoc rules, employing the features of various Codes (e.g., the Federal Emergency Management Agency, New Zealand, and Canada). The efficiency of this modeling effort is evaluated for each Code separately and it is clearly demonstrated that ML-based models are capable of outperforming currently established engineering practices. Furthermore, in the spirit of the aforementioned Codes, a linearization of the fully trained ML model is proposed. ML feature attribution techniques, namely SHapley Additive exPlanations (SHAP) are employed to introduce weights similar to engineering practices. The promising results motivate the potential applicability of this methodology towards the recalibration of the RVS procedures for various types of cases. [ABSTRACT FROM AUTHOR]

For medium- and small-span bridges, the weight of the superstructure in steel–concrete composite girder bridges is lighter than that of a reinforced concrete girder bridge. However, it is still uncertain whether steel–concrete composite girder bridges exhibit superior seismic performance compared to reinforced concrete girder bridges. This study quantitatively compared the seismic performance of the two types of bridges. Using the theory of probabilistic seismic demand analysis, the seismic vulnerability curves of bridges were derived. To conduct seismic demand analysis for probabilistic analysis on the OpenSEES platform, bridge samples were generated using the Latin hypercube stratified sampling method, which considers the uncertainties associated with the two types of bridges. The vulnerability curves of the piers, bearings, abutments, and the system of the two bridges were established using probabilistic analysis of the time history analyses. The results showed that the seismic vulnerabilities of components and the overall system of the steel–concrete composite girder bridge were both lower than those of the reinforced concrete girder bridge. When the peak ground acceleration (PGA) of the ground motion was 0.3 g, the moderate and serious damage probabilities of the piers in the steel–concrete composite bridge were only 54.61% and 60.89%, respectively, of those of the reinforced concrete bridge. Consequently, replacing the upper reinforced concrete girders with steel–concrete composite girders can significantly improve the seismic performance of a large number of existing bridges. [ABSTRACT FROM AUTHOR]

In Peru, confined masonry houses are self-built, which makes it crucial to determine their seismic vulnerability. The objective of the research was to estimate the seismic vulnerability of confined masonry dwellings in the Pueblo Libre-Jaén sector using assembly algorithms. A database was constructed with data obtained from the National Institute of Civil Defense (INDECI), scientific articles, and theses. Subsequently, the data set was divided into a training set (80%) and a validation set (20%), employing the stacking method with five combinations CB_1, CB_2, CB_3, CB_4, and CB_5. The basic algorithms Gradient-Boosting, Random-Forest, Extra-Tree, and Decision-Tree were utilized as the base algorithms, with the final estimator being the Random Forest Meta-Learner. The models were trained and validated in Python, achieving accuracies of 94.95, 95.48, 95.39, and 95.66 for the base models and 95.62, 95.23, 95.76, 95.90, and 94.80% for the ensemble models. The most accurate models were the simple Gradient Boosting (95.66%) and the assembled models CB_3 (95.76%) and CB_4 (95.90%). The CB_4 model, which is composed of the Decision Tree and Gradient Boosting algorithms, was applied to the Pueblo Libre sector and yielded a reliability estimate of greater than 95% for the seismic vulnerability of confined masonry. This estimate was classified as high (1.48%), moderate (32.85%), and low (65.67%). It is anticipated that the model implemented will enable engineers and authorities to implement mitigation measures to reinforce housing in the event of a seismic event. [ABSTRACT FROM AUTHOR]

Lifelines are the determining components of survival in today's modern world and if the service of these infrastructures is threatened or destroyed due to natural disasters (especially earthquakes) and military threats, the activities of the society are disrupted and the severe failure of these systems will prolong the reconstruction period. One of the most important vital infrastructures that has a direct relationship with people's lives is the need for a water network. A review of the past earthquakes of the world and Iran shows that the components of the drinking and non-drinking water supply system have historically been considerably poor. The main goal of this paper is to prepare a model to analyze the seismic vulnerability of the water network by considering its dependence on other networks. To determine the vulnerability analysis of the water network by considering dependencies, two models were used, graph theory and Leontief. Then, after drawing the network architecture, the proximity and uncertainty matrix of all features were extracted. By multiplying the transpose of the uncertainty matrix in the independent damage analysis of each feature, the dependent damage was determined. The analysis showed the significant impact of dependence on the damage estimate of water network infrastructure; in some elements, the damage increased up to 45 times compared to the independent state. The risk of water reservoirs, water pumping stations, and water wells increased by 92%, 87%, and 62%, respectively, from the independent situation compared to the dependence in the studied area. In the case of robustness of the water network compared to the current situation, the vulnerability of water tanks, water pumping stations, and water wells will be reduced by 25%, 22% and 32%, respectively.

This study aimed to perform a comprehensive Deterministic Seismic Hazard Assessment (DSHA) to quantify the Peak Ground Acceleration (PGA) values for the Lowari Tunnel region. Twelve thrust faults in the vicinity of the tunnel were evaluated using an updated earthquake catalog from 25AD to 2022. The PGA values were calculated for each thrust fault and compared with the designed value of 0.5 g from the feasibility stage of the tunnel. The study demonstrated that all twelve thrust faults exhibited PGA values below 0.5 g, indicating a low-to-moderate seismic hazard in the region. The maximum PGA value obtained in this study was 0.4 g, which is well below the maximum designed value, indicating that the tunnel is expected to withstand the ground motion values projected to result from high-magnitude earthquakes in the region. These findings hold significant importance as they provide crucial insights into assessing the long-term sustainability of the Lowari Tunnel, situated in one of the world's most seismically active zones. [ABSTRACT FROM AUTHOR]

The need to assess the vulnerability of non-engineered residential RCC buildings in Nepal has become urgent, especially considering the ongoing modifications and additions to these structures without understanding their susceptibility to seismic events. Many residential buildings, particularly those up to three stories, did not fully comply to the guidelines outlined in Nepal Building Code NBC 105:2020. Therefore, there is a necessity to assess the seismic performance of these structures. This study aims to quantify the seismic vulnerability of such buildings by focusing on three distinct types: regular two and three-story structures, and irregular three-story structures. Using finite element modeling, the analysis of the buildings' seismic capacity was performed through pushover analysis. Subsequently, linear time history analysis is conducted to determine the seismic demand. Two software were utilized to conduct the analyses, namely SAP2000 and STERA_3D. The study also includes the matching eleven strong ground motion inputs to Nepal's site characteristics and response spectrum to ensure the relevance of the local context. Furthermore, fragility curves are constructed to compare the probability of structural failure, by first conducting the nonlinear dynamic analyses on the building specimens. The result showed that the probability of complete failure rises rapidly when an additional story is constructed with vertical irregularity, increasing from 1.8% to 5.7% in a non-engineered two-story building. The study also observes variations in top displacement across all three buildings due to differences in earthquake duration and frequency. From the findings, it is revealed that a significant increase in seismic vulnerability for vertically irregular buildings compared to regular ones. [ABSTRACT FROM AUTHOR]

Constructing a seismic vulnerability assessment model is crucial for emergency response and mitigating seismic risk. In the wake of increased usage of machine learning, it helps the assessment model to produce more spatial and quantitative results with higher speed, providing a global view of seismic vulnerability in large areas. This paper explores the applicability and performance of different machine learning algorithms in vulnerability assessment. Three regression algorithms of supervised learning (multiple linear regression, BP neural network and support vector machine) are adopted for testing and validation of the models. The detailed vulnerability inventories of different categories of civil structures under Ludian earthquake are compiled according to field investigation and adopted as the training set. Various kinds of damage ratio are determined to consider the different degrees of impact on civil structures under earthquake. Four aspects of factors containing structure category, topographical, seismic, comprehensive factors are selected as independent variables. It is found that the prediction error shows distinctions in different categories of civil structures irrespective of the algorithms, suggesting the necessity of considering structure category in seismic vulnerability assessment using machine learning. Nonetheless, the highest success rates are obtained using BP neural network, with an RMSE of less than 0.05. [ABSTRACT FROM AUTHOR]

A multi-purpose and multi-scale tool for the seismic vulnerability and risk classification of critical buildings, such as schools, is proposed for pre- and post-event decision-making to mitigate the risk and reduce losses. The herein proposed "RiskSchools" system, is capable of performing the seismic risk assessment and grading of school buildings at various scales (district, municipality, region etc.), using (a) a pre-seismic rapid visual screening and grading of the school buildings in different vulnerability-risk classes and (b) a seismic risk assessment of the school buildings population, applying probabilistic or scenario-based methods for the seismic hazard and analytical methods for the vulnerability and risk assessment, also leading to a grading of the buildings' risk. The results of the two approaches are compared and combined through a flexible and adaptable expert elicitation scheme to provide a final classification of the seismic risk of the school buildings in the scale of interest and a prioritization scheme with respect to the need for seismic upgrade and retrofitting. The RiskSchools system consists of a powerful, state-of-the-art, user-friendly, and easy-to-use smartphone application for the compilation of the inventory and the rapid visual screening, and a project-dedicated multi-purpose webGIS platform for the seismic vulnerability and risk classification of school buildings at any scale. Although it is initially developed and applied to the school building stock of the Region of Central Macedonia in Greece, it has been specifically designed to be easily applied to other regions of Greece and worldwide and adapted to other critical buildings, like health care and hospital buildings. The ultimate scope of the RiskSchools System is to allow for the optimal design of decision-making procedures in support of disaster management to enhance critical buildings resilience. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)