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Probabilistic seismic hazard and risk models are essential to improving our awareness of seismic risk, to its management, and to increasing our resilience against earthquake disasters. These models consist of a series of components, which may be evaluated and validated individually, although evaluating and validating these types of models as a whole is challenging due to the lack of recognized procedures. Estimations made with other models, as well as observations of damage from past earthquakes, lend themselves to evaluating the components used to estimate the severity of damage to buildings. Here, we are using a dataset based on emergency post-seismic assessments made after the Le Teil 2019 earthquake, third-party estimations of macroseismic intensity for this seismic event, shake maps, and scenario damage calculations to compare estimations under different modelling assumptions. First we select a rupture model using estimations of ground motion intensity measures and macroseismic intensity. Subsequently, we use scenario damage calculations based on different exposure models, including the aggregated exposure model in the 2020 European Seismic Risk Model (ESRM20), as well as different site models. Moreover, a building-by-building exposure model is used in scenario calculations, which individually models the buildings in the dataset. Lastly, we compare the results of a semi-empirical approach to the estimations made with the scenario calculations. The post-seismic assessments are converted to EMS-98 (Grünthal, 1998) damage grades and then used to estimate the damage for the entirety of the building stock in Le Teil. In general, the scenario calculations estimate lower probabilities for damage grades 3–4 than the estimations made using the emergency post-seismic assessments. An exposure and fragility model assembled herein leads to probabilities for damage grades 3–5 with small differences from the probabilities based on the ESRM20 exposure and fragility model, while the semi-empirical approach leads to lower probabilities. The comparisons in this paper also help us learn lessons on how to improve future testing. An improvement would be the use of damage observations collected directly on the EMS-98 scale or on the damage scale in ESRM20. Advances in testing may also be made by employing methods that inform us about the damage at the scale of a city, such as remote sensing or data-driven learning methods fed by a large number of low-cost seismological instruments spread over the building stock. [ABSTRACT FROM AUTHOR]

Probabilistic seismic hazard assessments (PSHAs) provide the scientific basis for building codes to reduce damage from earthquakes. Despite their substantial impact, little is known about how well PSHA predicts actual shaking. Recent PSHA for California, Japan, Italy, Nepal, and France appear to consistently overpredict historically observed earthquake shaking intensities. Numerical simulations show that observed shaking is equally likely to be above or below predictions. This result from independently developed models and datasets in different countries and tectonic settings indicates possible systematic bias in the hazard models, the observations, or both. Analysis of possible causes shows that much of the discrepancy is due to a subtle and rarely considered issue: the conversion equations used in comparing the models--which forecast shaking as peak ground acceleration or velocity--and observations--parameterizations of qualitative shaking reports. Historical shaking reports fill a crucial data gap, but more research is warranted on how qualitative observations relate to instrumental shaking measures for earthquakes. [ABSTRACT FROM AUTHOR]

This study presents an updated view of the effects of the 1940 Vrancea earthquake. Recently compiled studies in the literature from the time of the event, as well as other studies, present the opportunity to gain additional and relevant information regarding this large-magnitude event. The effects of this earthquake on various locations in Romania are compared to those observed after the subsequent large Vrancea earthquake of 1977. An assessment of the economic losses caused by the seismic event is also attempted. The seismic vulnerability of some building typologies commonly used before 1940 is assessed by employing the earthquake damage data and the well-known macroseismic method. The impact of this event on the design and construction practices in Romania is evaluated using the collected information as well. Finally, the policy of repair and strengthening of buildings applied after the event is also discussed, and case studies are presented. [ABSTRACT FROM AUTHOR]

This paper investigates a method for improving the selection of seismic motions for designing earthquake-resistant underground structures. It is found that PGV alone is unreliable as a predictor of structural damage with increasing earthquake intensity. Therefore, based on characterizing seismic intensity by using PGV, another parameter, referred to here as "the severest parameter", is introduced to distinguish potential damage capacity for different seismic motions. A numerical model of a soil–underground structure system was established using the finite element software OpenSees. A total of 120 real ground motions were selected for the model, considering the influences of eight different site groups on the underground station and the rupture distances of the input seismic motions. The results show that as seismic intensity increases, substantial variability in the response of underground structures emerges under the same amplitude of PGV, diminishing the effectiveness of the relationship between PGV and structural damage. When assessing the potential damage capacity of seismic motions with similar or close amplitudes of PGV, VSI is an appropriate severest parameter for Class III sites and ASI is suitable for Class II sites. When the correlation coefficient between the severest parameter and the structural response is greater than 0.8, it can be used to reliably assess seismic damage capacity based on the size of the severest parameter. [ABSTRACT FROM AUTHOR]

Western China is a typical high-intensity seismic zone, where seismic and geological disasters are frequent. The tunnel portal slope is prone to earthquake damage, which has become the key and difficult point in engineering construction. To deeply explore the dynamic response characteristics and instability mechanism of high-steep slopes at tunnel portal under frequent earthquakes, a large-scale shaking table test was designed. This experiment mainly simulates the geological environment of a high-intensity earthquake area by applying microseismic waves several times. The test results show that the amplification coefficient of peak ground acceleration (PGA) at different stages decreases with increasing earthquake intensity and finally presents a 50% attenuation. The vertical wave has a greater effect on the dynamic response of the slope, mainly affecting the magnifying effect during the relative elevation of 0.3–0.7. The horizontal wave has a stronger amplification effect on the slope crest region. The nonconsistency of the acceleration amplification factor (MPGA) and the dynamic change characteristics of the ∆MPGA can well identify the three stages of slope failure: the elastic stage (0–2 m/s2), elastoplastic stage (2–5 m/s2), and plastic failure stage (≥ 5 m/s2). The seismic failure modes of the slope can be summarized as follows: tensile fracture is formed first at the crest and waist of the slope, shear failure occurs between the slope waist and tunnel, forming a sliding body gradually, and the slope toe uplifts and finally forms collapse failure. This work can provide a reference for the design of seismic technology for tunnel portal slopes in high-intensity areas. Highlights: To deeply explore the dynamic response characteristics and instability mechanism of the high steep slope at the tunnel portal under frequent earthquakes, a large scale shaking table test was designed, focusing on modelling the geological environment of high intensity seismic region. The roc k mass degradation effect of complex geological slopes in high seismic regions is simulated by applying microseismic wave forms near the study area for many times. By analyzing the peak ground acceleration and its amplification coefficient, the dynamic response characteristics and instability characteristics of the slope are systematically studied. Waves in different directions have different control effects on slope failure, and complex wave field superposition exists between the slope and tunnel syste m. Meanwhile, the acceleration amplification effect at different locations can assist in identifying slope damage areas. The dynamic failure modes of steep bedding slope with tunnel structures are as follows: tensile fracture shear failure sliding failure of upper slope, collapse failure of slope toe area. The formation and penetration of fissure mainly focus on the weak interlayers of slope surface. In addition, the interlayers are prone to shear failure area, which leads to shear slip of the slope under the seismic force, while the slope toe is prone to collapse failure due to the extrusion action. [ABSTRACT FROM AUTHOR]

Large earthquakes often damage water pipelines and disrupt the functionality of water distribution systems (WDS). This paper investigates the hydraulic performance of WDS following an earthquake, taking into account the postearthquake firefighting capacity of the system and the corrosion deterioration of pipelines. The seismic failure probability for corroded water pipes is calculated using a modified American Lifeline Alliance fragility function, and hydraulic simulations are performed using the water network tool for resilience. Water serviceability and the generalized resilience index are used as measures to determine the hydraulic performance of the WDS, which is evaluated under various conditions of network ages and seismic intensities. The framework developed in this study is exemplified for the Zhi Jiang (ZJ) WDS. The results indicate that, although firefighting does not significantly reduce performance measures, it is necessary to consider it in recovery plans since more customers are likely to lose a water supply due to postearthquake fires. The hydraulic behavior is worst in older WDS or those subjected to higher seismic magnitudes. Due to the scenario earthquake event, water serviceability reduces as the WDS ages, and the older networks require longer recovery times. Therefore, corrosion deterioration has a significant influence on the system-level seismic hydraulic performance. [ABSTRACT FROM AUTHOR]

The 14 April 1895 (Mw 6.1, in the area of Ljubljana, Slovenia) earthquake is still not fully understood. The aim of this work is to derive information about its source from the inversion of an updated dataset of intensities (evaluated with EMS-98). This was done via automatic non-linear geophysical inversion KF-NGA, which was performed using a Niching Genetic Algorithm and has been presented in other articles. The distribution of damage caused by this earthquake is not homogeneous and often shows significant intensity differences between neighbouring sites. Statistical analysis of the intensities, epicentral distances and geologic nature of the sites suggests some site effects. Nevertheless, the resulting solution is consistent with regional seismotectonics, i.e. an almost pure dip-slip mechanism: strike 282° ± 5°, dip 38° ± 7°, rake 86° ± 9° (± 180° because of the intrinsic ambiguity of the KF-NGA-inversion). Since the rake angle is close to 90°, there is an almost perfect ambiguity between the two planes of the focal mechanism. Therefore, our solution has a Dinaric direction and could be associated either with a fault plane that dips NE or with one that dips SW. [ABSTRACT FROM AUTHOR]

The Nankai Trough Earthquake, which is estimated to have a 70%–80% probability of occurring within the next 30 years, necessitates considering various scenarios due to the extensive seismic source region and call for advancing disaster preparedness measures. Assessing direct damage caused by earthquakes is considered particularly challenging compared to assessing human and physical damage due to its intricate composition. However, the existing research in model analysis aimed at real-time estimation has yielded results, namely, the ability to promptly calculate direct damage from earthquakes using seismic motion and stock quantities as inputs. This study aimed to leverage the research outcomes of real-time estimation to approximate the direct damage costs that would be caused by the Nankai Trough Earthquake. Three hazard assessment cases were selected, based on damage estimations to be attempted. The results indicated that a damage estimation approach based on a common foundation dataset and model analysis considering different occurrence scenarios is more suitable for evaluating results and assessing the importance of mitigation measures than conventional scenario-based damage estimations. [ABSTRACT FROM AUTHOR]

Seismic vulnerability modeling plays a crucial role in seismic risk assessment, aiding decision-makers in pinpointing areas and structures most prone to earthquake damage. While machine learning (ML) algorithms and Geographic Information Systems (GIS) have emerged as promising tools for seismic vulnerability modeling, there remains a notable gap in comprehensive geospatial studies focused on India. Previous studies in seismic vulnerability modeling have primarily focused on specific regions or countries, often overlooking the unique challenges and characteristics of India. In this study, we introduce a novel approach to seismic vulnerability modeling, leveraging ML and GIS to address these gaps. Employing Artificial Neural Networks (ANN) and Random Forest algorithms, we predict damage intensity values for earthquake events based on various factors such as location, depth, land cover, proximity to major roads, rivers, soil type, population density, and distance from fault lines. A case study in the Satara district of Maharashtra underscores the effectiveness of our model in identifying vulnerable buildings and enhancing seismic risk assessment at a local level. This innovative approach not only fills the gap in existing research by providing predictive modeling for seismic damage intensity but also offers a valuable tool for disaster management and urban planning decision-makers. [ABSTRACT FROM AUTHOR]

A series of earthquakes that struck Taiwan's southern Longitudinal Valley on September 17 and 18, 2022 severely damaged several buildings in Taitung and Hualien. The Chishang earthquake, which had a magnitude of ML 6.8 and a large foreshock with a magnitude of ML 6.6 the day before, was the mainshock in this sequence. The strongest intensity reported in the epicentral region during this earthquake sequence, which was 6 + , is the highest ever recorded since the Central Weather Bureau (CWB, renamed as the Central Weather Administration since September 15, 2023) revised its seismic intensity scale. National Taiwan University (NTU) has operated a low-cost earthquake early warning (EEW) system known as the P-Alert for a decade. In this study, we demonstrate the performance of the P-Alert network during the 2022 Chishang earthquake and the largest foreshock. The P-Alert network plotted shake maps during these earthquakes that displayed various values within 5 min. The high shaking areas on these maps were in good agreement with observed damages during this earthquake, providing valuable insights into rupture directivity, a crucial component of earthquake engineering. Individual P-Alert stations acted as on-site EEW systems and provided a lead time of 3–10 s within the blind zone of CWB. For the ML 6.8 mainshock, there was a lead time of at least 5 s, even up to 10 s, demonstrating their effectiveness in the blind zone. The P-Alert regional EEW system provided the first report about 9 s and 7 s after the mainshock and the largest foreshock occurrence, respectively, with estimated magnitudes of 5.74 and 5.67. The CWB system estimated magnitudes of 6.72 and 6.16 in the first report, respectively, about 7 s and 9 s after the earthquake occurrence. The timeliness of the two systems were not significantly different. Despite the effectiveness of the P-Alert network, data loss due to connection interruptions prompted us to develop a new compact data logger for improved data availability. [ABSTRACT FROM AUTHOR]

Introduction: Masonry minarets in Old Cairo are highly susceptible to earthquake damage, particularly those not designed or updated to withstand seismic loads. Therefore, regular monitoring is necessary to ensure their safety and detect any deterioration or reduction in seismic performance. The direct loss of a minaret can lead to the collapse or severe damage to the structure itself. The cascading impacts of partial or complete minaret failure can have significant consequences for the immediate vicinity and the broader community. By studying the effects of earthquakes on minarets and developing mitigation strategies, countries can take proactive measures to protect these structures and ensure the safety of people. Objective: This study focuses on a specific type of Islamic architecture: the historic minarets in Cairo. The research aims to evaluate the seismic vulnerability of eight cultural heritage minarets in Cairo, identifying the parameters influencing their seismic behaviour and susceptibility to earthquake damage. Methods: The research utilizes empirical seismic vulnerability methods and ambient vibration measurements on eight minarets. An empirical approach compatible with the nature and style of the minarets is employed to evaluate their vulnerability using index values and curves. The method's validity is assessed, and areas of conformity and limitations are identified. Ambient vibration tests (AVTs) are also conducted using a temporary seismic network installed at various heights inside each minaret to determine their dynamic characteristics. Results: The seismic vulnerability Index (I_V) is calculated for the selected minarets based on the state of each vulnerability parameter. The contribution of each parameter to the final I_V values of the minarets are presented. Vulnerability curves are developed for each minaret, interpreting the conventional vulnerability indexes in terms of mean damage grades for seismic events with varying intensity on the EMS-98 scale. These mean damage grades can also indicate the expected damage levels of structural and non-structural minaret elements for events with different seismic intensity levels. AVTs are conducted at various heights on the selected minarets, and the dynamic characteristics are extracted from the recorded data. Variations in these characteristics are considered significant for structural health monitoring analysis. The peak-picking method is employed to directly extract each minaret's natural frequencies and mode shapes, as changes in dynamic characteristics are relevant to health monitoring analyses. Conclusions: The recent study examined the seismic vulnerability assessment of eight masonry minarets in the historic Old Cairo district. The assessment revealed vulnerability index values ranging from 10.3 to 26.1, indicating a concerning susceptibility to seismic events among these structures. Vulnerability curves were constructed for each minaret, visually representing potential damage scenarios across different levels of the EMS-98 intensity scale. These outcomes are significant as they facilitate prioritizing interventions to safeguard the most vulnerable minarets. Additionally, a novel empirical period equation was introduced to estimate the fundamental period of minarets in Old Cairo based on their heights. The equation was validated against field measurements and data from the literature. The study is limited by its focus on a specific category of minarets, specifically the historical masonry minarets in Old Cairo. Furthermore, limitations arise from the need for detailed finite element models to capture these minarets' dynamic responses accurately. Therefore, ongoing research involves the development of detailed finite element models and calibrating fundamental periods for the selected minarets. The anticipated results hold the potential to enhance our understanding of the structural dynamics of historical minarets, ultimately guiding the formulation of tailored seismic retrofitting and preservation strategies. These strategies, aimed at preserving these cherished cultural heritage assets, represent our collective commitment to ensure the endurance of these timeless landmarks for future generations. [ABSTRACT FROM AUTHOR]

The northern part of Pemalang City consists of Quaternary deposits, having the potential for earthquake amplification effect. This amplification effect amplifies the ground shaking because of an earthquake (the local site effect) that has the potential to cause damage. This study investigated the amplification factor from the HVSR curve of microtremor measurements due to soil response based on ground shear strain, the risk level of the earthquake based on peak ground acceleration (PGA), and earthquake intensity. The microtremor data from five locations in Pemalang were used to calculate the amplification factor and predominant frequency. The damaging earthquake parameters around Java during 2010-2020 were used to calculate the PGA. The microtremor data were processed using the HVSR method, and PGA was calculated using the Kanai equation. The HVSR result shows that Pemalang has an amplification factor ranging from 6.23 to 19.59 and ground shear strain varying between 0.86 x 10-4 and 6.67 x 10-4, which shows that Pemalang only experiences the vibration when an earthquake occurs. The PGA results using the Kanai equation (19.71-54.56 gal) were included in the low vulnerability category, and MMI earthquake intensity (3.08-4.70) was included in the felt earthquake category (II SIG BMKG scale). Therefore, the amplification factor from the HVSR curve of microtremor measurement, ranging from 6.23 to 19.59, showed low soil response and low-risk vulnerability based on the damaging earthquake parameter around Java during 2010-2020. [ABSTRACT FROM AUTHOR]

The code-based response modification factors are mainly developed based on engineering judgments and experiences from past earthquakes, and hence, they may not lead to reliable solutions considering different performance targets and hazard levels. On the other hand, the uncertainties associated with these proposed values are more significant for new lateral load-carrying systems, such as tunnel-form buildings, due to insufficient information about their performance against seismic events. To address these challenges, this study aims to propose a multi-level approach for the estimation of response modification factors for tunnel-form building structures by taking into account the site seismicity and the damage level defined as the target performance. Using the proposed approach, the modification factors corresponding to different ranges of earthquake intensity and damage levels are obtained for 2-, 5-, 7-, and 10-storey tunnel-form buildings. The results are then used to verify the efficiency of the response modification factors proposed by design codes for the preliminary design (code-based factors) of such systems. It is shown that, in general, by adopting a response modification factor between 4 and 6, the tunnel-form structural systems exhibit excellent seismic performance and can satisfy the requirements of the Immediate Occupancy (IO) performance level even under the Maximum Considered Earthquake (MCE). The outcomes of this study could be useful for performance-based design of tunnel-form building structures aligned with the new generation of seismic design codes. [ABSTRACT FROM AUTHOR]

This study is aligned with United Nations, Sustainable Development Goal 11, concerned about making cities and human settlements inclusive, safe, resilient and sustainable, in particular, in line with resilience to disasters, and protecting the world's cultural heritage targets. Focused on a small sample of rammed earth residential dwellings in the city of Mula, one of the areas of highest seismic hazard in Spain, the seismic vulnerability has been assessed adapting the Vulnerability Index Method (Risk-UE) to tackle the specificities of earthen residential buildings. The majority of this humble earthen heritage, despite being an essential part of the Spanish Culture, suffers from the effects of abandonment and insufficient maintenance. As a consequence, these genuine buildings will be seriously damaged in the event of an earthquake of intensities from VII to VIII, with heritage losses representing 17% to 43% of the built area. These research outcomes can be used to define repair and strengthening priorities among the buildings in the sample when financial resources are limited. The proposed indices and coefficients can be applied to similar earthen structures, widely built in the Iberian Peninsula and the Mediterranean region. [ABSTRACT FROM AUTHOR]

Studies on earthquake-related damage underscore that buildings are vulnerable to significant harm or even collapse during moderate to strong ground motions. Of particular concern is seismic-induced pounding, observed in numerous past and recent earthquakes, often resulting from inadequate separation gaps between neighboring structures. This study conducted an experimental and numerical investigation to develop a mathematical equation to calculate a sufficient separation gap in order to avoid the collision between adjacent mid-rise steel-frame buildings during seismic excitation. In this study, the coupled configuration of 15-storey & 10-storey, 15-storey & 5-storey, and 10-storey & 5-storey steel frame structures was considered in the investigation. The investigation concluded with a large number of data outputs. The outputs were used to predict structural behavior during earthquakes. The obtained data were categorized into three main categories according to the earthquake's Peak Ground Acceleration (PGA) levels. Also, the derived equations were divided into three different equations to estimate the required seismic gap between neighboring buildings accordingly. The derived equations are distilled to empower engineers to rigorously evaluate non-irregular mid-rise steel frame buildings. [ABSTRACT FROM AUTHOR]

For simulating the dynamic rupture process in earthquake scenarios, the stress distribution along the fault remains unclear owing to a lack of direct measurements. Regional stress fields are often resolved onto the fault plane to determine the stress distribution along it. To overcome this limitation, we considered different interseismic locking models to better constrain the actual stress distribution. Specifically, we took the Suoerkuli section in the middle of the Altyn Tagh fault, China, and conducted dynamic rupture simulations to obtain possible earthquake scenarios. The surface rupture length and moment magnitude obtained from the simulations were consistent with those of historical earthquakes. Compared with the traditional stress field resolution method, our approach led to better constrained fault rupture extent and distribution characteristics of regional intensity, thereby avoiding overestimations of earthquake damage. We conclude that examining regional seismic hazards and risks based on seismic dynamic rupture simulations that account for the locking ratio of the fault plane is advantageous, and should be encouraged. [ABSTRACT FROM AUTHOR]

The 1923 Kanto earthquake (MJ=7.9) has great significance for seismic hazard assessments of the Tokyo metropolitan area, because it caused extensive damage to the area. To deepen our understanding of the strong ground motion of the Kanto earthquake, this paper reviewed studies on its observed strong ground motion and found that 1) seismic intensity VI on the Japanese scale (IX or X on the M. M. scale) was widely distributed in an area of approximately 8,000 km2, which is equivalent of that of the 2011 M9 Tohoku earthquake, 2) strong effects of soil amplification on ground motion were suggested by the correlation of the damage distribution with surface geology, 3) the restoration of the scaled-out seismogram indicated that the ground motion at the upland of Tokyo would be roughly 50 cm/s for maximum velocity and 50 cm for maximum displacement, and 4) the ground motion in the epicentral area is unclear, but would be roughly twice or more as strong as that at Tokyo. [ABSTRACT FROM AUTHOR]

The performance-based seismic design pretends to take care of the lives of the occupants and reduce the cost of damage caused by earthquakes. Several ways of estimating damage and economic losses have been developed, but most of them lack objectivity and have great dispersion in the results. In the last decade, the advancement of technology has allowed the appearance of new methodologies, such as the one developed by the Pacific Earthquake Engineering Research Center (PEER methodology). However, the information regarding application and scope is scarce. In the present investigation, the economic seismic performance for a steel building was determined by applying the PEER methodology with different levels of seismic intensity. A multi-family residential model of special moment frames (SMF) was used, and the structure was designed by means of modal analysis. Spectral, incremental dynamic non-linear analysis was performed where the structural response was determined, with the help of the PACT software. The seismic performance, expressed as the repair costs, repair times, deaths, and injuries, was defined. The results obtained indicate that buildings designed with traditional structural standards can be demolished after the action of an earthquake because the repair costs exceed 40% of the replacement cost. Rare and very rare seismic events can cause the total suspension of the service and a considerable number of deaths and injuries. [ABSTRACT FROM AUTHOR]

An earthquake of magnitude 6.7 M (Latitude 24.834N; Longitude 93.656E) on the Richter scale rocked in the Noney area, Tamenglong district, Manipur on 4th January 2016. The shock was strongly felt in most parts of the Northeastern states of India viz. Manipur, Nagaland, Meghalaya, Assam, and its neighboring countries Myanmar and Bangladesh. Macroseismic study was conducted to assess the intensity of ground motion and related damages caused by the earthquake. The damage incidences were mainly reported in structures constructed over the alluvial fill material. Deformations and development of ground fissures were observed in the epicentral tracts of Manipur and liquefaction phenomenon was observed in the Silchar area Assam. The study revealed that higher damage was confined to the area around Noney, Kabuikhullen, Nungba, Leimakhong, and Imphal valley areas in Manipur and Silchar town areas in Assam. Based on field observation, the degree of damage to building structures, and data gathered from the local population using the standard questionnaire, different intensity values were assigned to each locality. Isoseismal map was prepared by drawing the boundaries between different intensity areas at MSK-64 scale. The result indicates that the intensity was within the range of IV to VII. The maximum intensity was found VII in parts of Imphal, Tamenglong, and Silchar and very close to the epicentral tract area of Noney; and lowest intensity IV was observed in other parts of the northeastern states around Dimapur and Kohima in Nagaland state. The location of the epicenter of main shock (M 6.7) was at the intersection of the two major lineaments trending to ENE-WSW and NW-SE. The trend and shape of isoseismals drawn on seismotectonic/geological maps are elliptical along ENE-WSW direction and are found more closely spaced in the north and southern parts of the affected area. The elliptical nature of the isoseismals indicates that this seismic event was caused by movement along a linear surface. Furthermore, the orientation of elliptical isoseismals with a major axis trend in an ENE-WSW direction is almost parallel to the ENE-WSW trend of major lineament/fault in the area. As a result, the ENE-WSW lineament/ fault trend appears to be the causative fault for this quake. In addition, one of the nodal plane (NP2) striking 83°, with dip 81° and slip (rake) 38° obtained from fault plane solution USGS shows a similar trend to the direction of generated elliptical isoseismals pattern confirming the event ocurred along a major tectonic lineament in a strike-slip mechanism. [ABSTRACT FROM AUTHOR]

This paper presents fragility functions for clay brick unreinforced masonry (URM) buildings that were developed using the data of damage and earthquake intensity by the September 24, 2019, Mirpur, Azad Jammu and Kashmir earthquake. These data were collected through reconnaissance surveys in the affected region. The intensity of the earthquake ranged from V to VII on the Modified Mercalli Intensity scale in the surveyed areas. The damage to clay brick piers of bridges was caused by compression or shear-compression forces applied by the vertical seismic forces. Most of the damaged URM buildings showed in-plane wall cracking with very few cases of out-of-plane wall failure. The damage in these buildings was influenced by both the ground motion's horizontal component and ground motion amplification due to site conditions. The damage types to the URM buildings in the surveyed areas were classified into five damage grades and these data were employed to propose fragility curves for clay brick URM buildings. [ABSTRACT FROM AUTHOR]

Wood-frame structures are used in almost 90% of residential buildings in the United States. It is thus imperative to rapidly and accurately assess the damage of wood-frame structures in the wake of an earthquake event. This study aims to develop a machine-learning-based seismic classifier for a portfolio of 6,113 wood-frame structures near the New Madrid Seismic Zone (NMSZ) in which synthesized ground motions are adopted to characterize potential earthquakes. This seismic classifier, based on a multilayer perceptron (MLP), is compared with existing fragility curves developed for the same wood-frame buildings near the NMSZ. This comparative study indicates that the MLP seismic classifier and fragility curves perform equally well when predicting minor damage. However, the MLP classifier is more accurate than the fragility curves in prediction of moderate and severe damage. Compared with the existing fragility curves with earthquake intensity measures as inputs, machine-learning-based seismic classifiers can incorporate multiple parameters of earthquakes and structures as input features, thus providing a promising tool for accurate seismic damage assessment in a portfolio scale. Once trained, the MLP classifier can predict damage classes of the 6,113 structures within 0.07 s on a general-purpose computer. [ABSTRACT FROM AUTHOR]

Probabilistic seismic hazard and risk models are essential to improving our awareness of seismic risk, to its management, and to increasing our resilience against earthquake disasters. These models consist of a series of components, which may be tested and validated individually, however testing and validating these types of models as a whole is challenging due to the lack of recognised procedures. Estimations made with other models, as well as observations of ground shaking and damages in past earthquakes lend themselves to testing the components for ground motion modelling and for the severity of damage to buildings. Here, we are using observations of damages caused by the Le Teil 2019 earthquake, third-party estimations of macroseismic intensity for this seismic event, and ShakeMap analyses in order to conduct tests on estimations made with scenario simulations using components of the 2020 Euro-Mediterranean Seismic Hazard Model and the European Seismic Risk Model. The tests concern the number of damaged buildings, the grade of damage, estimated ground motion intensity measures, and macroseismic intensity. In some scenarios, the models forecast shaking and damage consistent with the observations, while major divergences from observations are attributed to factors external to the tested models, such as the location of the hypocentre. [ABSTRACT FROM AUTHOR]

On February 6, 2023 (local time), two earthquakes (Mw7.8 and Mw7.7) struck central and southern Turkey, causing extensive damage to several cities and claiming a toll of 40,000 lives. In this study, we propose a method for seismic building damage assessment and analysis by combining SAR amplitude and phase coherence change detection. We determined building damage in five severely impacted urban areas and calculated the damage ratio by measuring the urban area and the damaged area. The largest damage ratio of 18.93% is observed in Nurdagi, and the smallest ratio of 7.59% is found in Islahiye. We verified the results by comparing them with high-resolution optical images and AI recognition results from the Microsoft team. We also used pixel offset tracking (POT) technology and D-InSAR technology to obtain surface deformation using Sentinel-1A images and analyzed the relationship between surface deformation and post-earthquake urban building damage. The results show that Nurdagi has the largest urban average surface deformation of 0.48 m and Antakya has the smallest deformation of 0.09 m. We found that buildings in the areas with steeper slopes or closer to earthquake faults have higher risk of collapse. We also discussed the influence of SAR image parameters on building change recognition. Image resolution and observation geometry have a great influence on the change detection results, and the resolution can be improved by various means to raise the recognition accuracy. Our research findings can guide earthquake disaster assessment and analysis and identify influential factors of earthquake damage. [ABSTRACT FROM AUTHOR]

For shield tunnels, seismic isolation layer is an effective countermeasure to reduce structural damage during earthquakes. In this paper, the physico-mechanical properties of asphalt-cement (A-C) materials applied to backfill grouting of shield tunnels were investigated by laboratory tests. Then, fragility curves were developed by analytical approach for shield tunnels before and after setting three typical A-C isolation layers (i.e. A-C Iso-layer1, 2, and 3), which were used to express the seismic vulnerability of tunnel lining and evaluate the seismic-reduction effectiveness under earthquakes. The results reveal that A-C isolation layers are effective in seismic-reduction under excitation of low input intensity (less than 0.5 g), while its effect is not significant at high-input intensity. The fragility curves for tunnel lining after setting A-C isolation layers show less vulnerability than not setting one at all seismic intensity levels. From the perspective of damage probability, the seismic-reduction effectiveness decreases with the increasing shear modulus of A-C isolation layer. The probability of minor damage of examined tunnel lining setting up with A-C Iso-layer1 decreased from 23% to 15% at most. [ABSTRACT FROM AUTHOR]

When the high-speed railway (HSR) bridge is subjected to earthquakes, some components in the HSR bridge are damaged, and these components' damages will be reflected in the deterioration of the rail unevenness. In this study, a framework to address the lateral seismic rail unevenness corresponding to the damages of different components in the HSR track-bridge subjecting to earthquakes is developed. In the first place, a benchmark HSR track-bridge system is selected to conduct the nonlinear dynamic analysis, and the distribution law of the seismic residual drifts in the HSR track-bridge system subjecting to different earthquake intensity levels is proposed. Next, a refined mapping model is developed to assess the additional rail unevenness corresponding to the damages of different components in the system. The seismic rail unevenness sample is established by combining the initial and additional rail unevenness. Finally, the assessment method for the power spectrum density (PSD) of the seismic rail unevenness is introduced, and the PSD assessments of rail unevenness corresponding to the seismic damages of different components in the HSR track-bridge system are developed. The proposed methodology provides an innovative approach to assessing the seismic damage status of the HSR track-bridge subjecting to random earthquakes. [ABSTRACT FROM AUTHOR]

A 6.9 magnitude earthquake at a depth of 10 km struck Menyuan County, Haibei Prefecture, Qinghai Province, China, on January 8, 2022. This earthquake damaged some railway bridges on the Lanzhou-Xinjiang Passenger Dedicated Line. This study combines relevant historical earthquake damage experience, considers the effects of earthquake intensity, site soil classification, superstructure type, foundation failure factor, number of spans, and total bridge length, and develops empirical formulas for seismic damage prediction of railway bridges using ordinal logistic regression model in SPSS software. Since the accuracy of both predictions for seismic damage is practically the same, using this regression to predict seismic damage to railway bridges is considered valid. The predicated seismic damage matrix, as were the anticipated multi-intensity mean damage index and the empirical vulnerability curve based on the two-parameter lognormal distribution function, were generated on this basis. We get a risk assessment of future seismic damage for regional bridges when they experience different intensities or peak ground acceleration. According to the conclusions, although the suggested particular equations and vulnerability curves do not apply to the remainder of the region owing to geographical uniqueness, the technical approach is valid. It may be used as a reference for seismic damage prediction and vulnerability evaluation in other regions. The earthquake damage prediction matrix derived from the regression analysis can provide reasonable and fast forecasts before the next earthquake. [ABSTRACT FROM AUTHOR]

The structure is said to be damaged if there is a permanent shift in the post-event natural frequency of a structure as compared with the pre-event frequency. To assess the damage to the structure, a time-frequency approach that can capture the pre-event and post-event frequency of the structure is required. In this study, to determine these frequencies, a local maximum synchrosqueezing transform (LMSST) method is employed. Through the simulation results, we have shown that the traditional methods such as the Wigner distribution, Wigner–Ville distributions, pseudo-Wigner–Ville distributions, smoothed pseudo-Wigner–Ville distribution, and synchrosqueezing transforms are not capable of capturing the pre-event and post-event frequency of the structure. The amplitude of the signal captured by sensors during those events is very small compared with the signal captured during the seismic event. Thus, traditional methods cannot capture the frequency of pre-event and post-event, whereas LMSST employed in this work can easily identify these frequencies. This attribute of LMSST makes it a very attractive method for post-earthquake damage detection. In this study, these claims are qualitatively and quantitatively substantiated by comprehensive numerical analysis. [ABSTRACT FROM AUTHOR]

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High-speed railway lines always have to cross the seismic zone with great earthquake risks leading to serious consequences. A replaceable steel panel damper (SPD) is proposed as an energy-dissipation device to mitigate the structural seismic responses. It is simulated as a simplified nonlinear spring embedded in structural system with the force–displacement behavior derived by plate-beam theory. To investigate the effect of SPD, a typical 5-span high-speed railway simply supported bridge-track system (HSRSBTS) validated by a shaking table test is established by ANSYS. A novel damage measure, the system relative damage ratio (γSRD), is proposed to quantify the effect of SPD in the system and consider the potential component-level damage modes of both bending and shear. The structural system is investigated undergoing two ground motions suites in DBE- and MCE-level intensity, including both far-field and near-field records in transverse direction. The result indicates that a significant reduce (roughly 50%) of seismic response in rail and girder are contributed by SPD, while the system damage decreases about 10–15%, especially for near-field pulse-like ground motions with high intensity. The energy-dissipation capacity of SPDs with various configurations is examined to optimize the properties of SPD. It generally decreases with the increase in the elastic stiffness ratio r of the SPD to the fixed support, and the r = 2–2.5 are recommended in engineering practice. SPD is an effective and efficient device of structure to be adopted as an energy-dissipation component and the first defense line under far-field and near-field ground motions. [ABSTRACT FROM AUTHOR]

UnReinforced Masonry (URM) buildings constitute the majority of the Italian building stock and represent one of the most vulnerable construction typologies, as emerged during the seismic events occurred in the last decades. The objective of the present work is the proposal of a methodology for the seismic vulnerability and fragility assessment of different typologies of URM buildings. Through the statistical analysis of post-earthquake damage survey forms and of census data, the most prevalent structural typologies were identified in the Emilia Romagna region (Italy), leading to the definition of two reference masonry buildings, built at the beginning of the XX century and representative of the building stock of the study area. These buildings were modeled according to the equivalent frame method and their seismic performance was studied by means of nonlinear static analyses, considering uncertainties on the mechanical properties of masonry, on the intensity of the seismic action and on the displacement demand calculation method. Through the definition of Response Surfaces, analytical fragility curves relative to the investigated structural typologies were determined for the different damage states. [ABSTRACT FROM AUTHOR]

Earthquakes have and continue to, occur worldwide, though some places are affected more than others by earthquake-induced ground shaking and the same earthquake can cause more damage in one area than in nearby locations due to site-specific geological site conditions, also known as local site effects. Depending on the chronology of the earthquakes, various disciplines of seismology include instrumental and historical seismology, archaeoseismology, palaeoseismology and neotectonics, each focusing on using specific sources of information to evaluate recent or ancient earthquakes. Past earthquakes are investigated to expand the pre-instrumental and instrumental earthquake catalog and better evaluate a region's seismic hazard. Archaeoseismology offers a way to achieve these goals because it links how ancient civilizations and their environment might have interacted and responded to past earthquake-induced ground motion and soil amplification. Hence, archaeoseismology explores pre-instrumental (past) earthquakes that might have affected sites of human occupation and their nearby settings, which have left their co-seismic marks in ancient manufactured constructions exhumed by archaeological excavations. However, archaeoseismological observations are often made on a limited epicentral area, poorly constrained dated earthquakes and occasionally on unclear evidence of earthquake damage. Archaeological excavations or field investigations often underestimate the critical role that an archaeological site's ancient geological site conditions might have played in causing co-seismic structural damage to ancient anthropogenic structures. Nevertheless, the archaeological community might document and inaccurately diagnose structural damage by ancient earthquake shaking to structures and even estimate the size of past earthquakes giving little or no consideration to the role of geological site effects in addressing the causative earthquake. This mixture of factors frequently leads to imprecise estimates of the size of ancient earthquakes and unlikely earthquake environmental impacts, leaving unexplained the location and the moment magnitude of the causative earthquake. Hence, it is essential not to rely solely on earthquake intensities based on archaeologically documented co-seismic damage without assessing the nature of the observed structural damage and the contribution of the geological site effects. This paper explains the geological site effects concept to archaeologists unfamiliar with the notion. It clarifies its role in assessing ground shaking, soil amplification and earthquake intensity by past earthquakes and how and why the geological site effects can be estimated when a site is thought to have been struck by an earthquake. Hence, the geological site effects must be considered when archaeological excavations describe and interpret destruction layers. Conversely, engineers and seismologists dealing with seismic hazard risk assessment must pay close attention to archaeological investigations assessing earthquake intensities and locations based on field evidence of damage to structures attributed to past earthquakes, because the geological site effects might have been factored in inaccurately or not at all. [ABSTRACT FROM AUTHOR]

In earthquake-prone regions, the evaluation of seismic impacts on bridges is crucial to mitigation, emergency, and recovery planning for highway networks. The degree of bridge damage determines the cost and time required for repairs and the level of post-earthquake functionality including disruption of transportation network, increased costs due to reduction of traffic flow and restricted access to emergency routes. The article presents the methodological development and implementation of an interactive web application for rapid geospatial assessment and visualisation of earthquake damage scenarios of municipal highway bridge networks based on open access datasets. The proposed framework consists of the following successive models: hazard, inventory, damage, and impact. The seismic hazard model generates spatial distribution of the shaking intensity for earthquake scenarios in terms of ground motion intensity measure using ground motion prediction equations based on seismic hazard model for Eastern Canada. The shaking intensities are then modified with local site amplification factors based on the Canadian highway bridge design code values. The inventory model provides a database of existing bridges based on open-access data which are then classified according to their seismic vulnerability. The damage model assesses seismic performance of classes of bridges by applying respective fragility functions represented as probabilistic relationships between the intensity measure and the degree of expected damage. The impact model evaluates the post-earthquake traffic-carrying capacity of the highway network based on the predicted damage including repair cost as a percentage of replacement cost of bridges and inspection priority. The web-application is demonstrated with a bridge network in Quebec City including 117 bridges subjected to 180 earthquake scenarios. The proposed methodology is particularly useful to facilitate direct communication of potential impacts to emergency managers and city transport officials. [ABSTRACT FROM AUTHOR]

This paper presents a rapid or real-time estimation method of the economic value of direct stock damages caused by significant earthquakes in Japan. The result will contribute to both the government and private sectors' early decision-making, particularly for provisional budget allocation. First, we developed a simple but evidence-based model for estimating stock losses explained by a representative earthquake hazard factor and an exposure factor, i.e., seismic intensity and existing stock of physical assets. The key characteristic of our estimation model is that the dependent variable is prefectural damage amount. Still, the explanatory variables come from municipal sources: we overcome this data availability problem through our estimation process. Second, we carefully checked the model's specification, estimation, and performance to be soundly applied to a real-time assessment of future earthquake events. We also explain the automated measuring of the prefectural direct loss value and its distribution to every 250 m mesh. Finally, we show two examples of the application of our model; one is the case of the 2018 Northern Osaka Earthquake, and the other is the anticipated Tokyo inland earthquake. [ABSTRACT FROM AUTHOR]

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This paper explores and validates the use of ground shaking scenarios generated via 3D physics-based numerical simulations (PBS) for seismic fragility studies. The 2009 L'Aquila seismic event is selected as case-study application, given the availability of a comprehensive post-earthquake database, gathering observed seismic damages detected on several building typologies representative of the Italian built environment, and of a validated numerical model for the PBS of ground shaking scenarios. Empirical fragility curves are derived as a function of different seismic intensity measures, by taking advantage of an improved statistical technique, overcoming possible uncertainties in the resulting estimates entailed by data aggregation. PBS-based fragility functions are compared to the corresponding sets of curves relying on updated ShakeMaps. The predictive capability of the adopted simulation strategies is then verified in terms of seismic damage scenarios, by respectively coupling PBS- and ShakeMap-based fragility models with the corresponding ground shaking scenarios. Comparison of observed and predicted damage distributions highlights the suitability of PBS for region-specific seismic vulnerability and risk applications. [ABSTRACT FROM AUTHOR]

Although some studies have been conducted to compute fragility surfaces of buildings using vector-valued seismic intensity measures (IMs), in all the cases, the first component of the vector usually is the spectral acceleration at first mode of vibration of the structure Sa(T1). In this study, fragility surfaces of three reinforced concrete buildings (RCB) subjected to narrow-band ground motions obtained from soft soil of Mexico City are computed considering vector-valued IMs based not only on Sa(T1), but also the velocity V(T1), pseudo-velocity Sv(T1), and normalized input energy by the mass EI/m(T1) as the first component. As second component of the vector-valued IMs, the Peak Ground Acceleration (PGA), Peak Ground Velocity (PGV), effective duration (tD), earthquake damage potential (ID) and four Np spectral shape-based parameters obtained through spectral acceleration (NpSa), velocity (NpV), pseudo-velocity (NpSv), and input energy (NpEI) have been analyzed. In order to obtain fragility surfaces, Multinomial Logistic Regression (MLR) was applied. It is observed that those vector-valued IMs based on the spectral shape proxies were more efficient to predict the probability of failure of RCB. For this reason, it is important to consider spectral shape vector-valued IMs in order to reduce uncertainty in the structural response of buildings under earthquakes. Thus, the use of two parameters instead of a single intensity measure improves the efficiency. Moreover, the fragility surfaces can be used for the seismic risk evaluation of buildings. [ABSTRACT FROM AUTHOR]

As regards the earthquakes occurred in Romania both in the pre-instrumental and instrumental era, as it is already known, besides Vrancea subcrustal earthquakes that strongly lay their mark on Romania's seismicity, significant impact results from the earthquakes generated by crustal seismic sources, with high intensity near the epicenter, including in the trans-border regions. Such an earthquake occurred at the end of the 19th century, on 14 October 1892, at 6.50 a.m. (GMT), that caused serious damage in some places in Bulgaria-Romania trans-border area, among the densely populated cities of both countries and just only 100 km away from Bucharest, 145 km from Constanta respectively. In this study we present historical information about the macroseismic effects of this trans-border crustal earthquake, descriptions that were obtained as a result of searching in various types of historical sources. Each available historical information was evaluated and the corresponding macroseismic intensity assigned in terms of the MSK macroseismic scale. [ABSTRACT FROM AUTHOR]

The 2022 MS 6.9 (MW 6.6) Menyuan earthquake occurred in the northeastern Tibetan Plateau and was recorded by a large number of recently installed micro-electro-mechanical system (MEMS) stations within 100-km fault distance. By comparing the pre-event noises and earthquake signals in time domain and frequency domain, it is found that the records are feasible to be used to analyze ground motion parameters. These records provide a database for analyzing the main features of the ground motions recorded by MEMS stations, in terms of ground motion models (GMMs), near-field impulsive characteristics, and seismic intensities. The observed ground motion parameters are compared with the predicted values by Boore et al. (Earthq Spectra 30(3):1057–1085, 2014) GMM model, and it is found that the GMM model predicts higher shaking at the short and medium periods and lower shaking at the long periods. However, the shaking intensities at the short periods for Central Italy 2016 earthquake sequence are well predicted by the GMM model. The observed Chinese seismic intensity (CSI) by instruments is compared with modified Mercalli intensity (MMI) and surveyed macroseismic intensity (SMI), and it is found that CSI values are 0.73 intensity unit greater than MMI values and high SMI can be well predicted by CSI. Ground motions at three stations are classified as pulse-like based on the methodology by Baltzopoulos et al. (Bull Seismol Soc Am 110(4):1495–1505, 2020), and whether the pulses have been caused by forward directivity or fling step is discussed, and only one station may be directivity related and the other two are still inconclusive. Finally the earthquake damage of a high-speed railway bridge in the intensity IX area is presented. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office 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.)

Earthquakes are one of the most life-threatening natural disasters for human beings. Since earthquakes cannot be accurately predicted, among the most important tasks of the postearthquake emergency response are to assess the damage in a timely manner, to perform emergency command and rescue, and to prevent secondary disasters. To ensure a smooth start to post-earthquake work, a reliable rapid earthquake disaster assessment system needs to be established, so that effective earthquake assessment results can be quickly obtained after the earthquake, which can help in the rescue and material distribution. Therefore, in this study, we attempt to establish a framework for a rapid earthquake disaster assessment system. The framework includes three modules: the rapid assessment of earthquake intensity, the estimation of economic damage and casualties, and the distribution of rescue materials. We use methods such as regression and entropy methods for the rapid assessment of earthquakes and obtain the results of earthquake intensity analysis, casualty prediction, economic loss prediction, and relief material distribution after an earthquake. These results can help the government in its postearthquake activities and can also give the public a clearer picture of the impact of the earthquake. The error between the earthquake intensity analysis results and the actual situation is about 21%, which is in line with the Chinese disaster mitigation and emergency response requirements (error < 30%), giving our results a high reference value. In the material distribution, multiple dimensions are introduced for the analysis and a reasonable value is obtained. The system can calculate the results within 2 min after obtaining the input data, demonstrating its timeliness. Moreover, on the basis of the established system, we attempt to design a rapid assessment platform for earthquake disaster, which can help the assessment and rescue in future earthquake disasters. The system can be experienced by visiting https://earthquick.peteralbus. com/. [ABSTRACT FROM AUTHOR]

The article considers the earthquake of April 5, 2017 with MWGCMT = 6.0 near the Turkmen–Iranian border, northeast of the Iranian village of Sefid Sang. During the entire seismic history of the region, this was the strongest seismic event within a 45 km radius of the epicenter. The earthquake caused widespread destruction in four villages; two people died and 100 were injured. The shaking was felt in population centers in Iran, Turkmenistan, and other countries. According to the compiled isoseist map, the northwestern orientation of isolines of equal intensity, coinciding with the strike of the nearest faults, and strong damping of the shaking intensity across tectonic structures were established. The macroseismic field equation has been established, which is close to the Blake–Shebalin equation with average world coefficients. According to both equations, the shaking intensity at the epicenter is estimated as I0 = 8. The northwestern (southeastern) orientation of the aftershock cluster and their southeast migration were revealed, which made it possible to choose the nodal plane of the focal mechanism with a similar strike as the active one. The fault plane parameters, length L = 30 km and width W = 12 km, have been estimated for the area of the highest aftershock density. The law of the decrease in the number of aftershocks with time has been established, which indicates rapid decay of the aftershock process. [ABSTRACT FROM AUTHOR]

Site characterization of metropolitan areas, especially after an earthquake, is of paramount importance for interpretation of spatial damage distribution and taking measures that assure realistic design actions to strengthen existing constructions and create new ones. Such a case is the city of Durres, Albania, that was hit by the disastrous earthquake of 26 November 2019 (M6.4). Significant differences in structural damage were observed throughout the city, despite its uniform epicentral distance (approximately 15 km); this could be either due to varying vulnerability of the affected constructions and/or to spatial variation of strong ground motion in the city, resulting from local site effects; the latter factor was investigated in this study. This was achieved by taking single station ambient noise measurements throughout the city, at approximately 80 sites. Ambient noise measurements are favorable, as acquiring ambient noise data is an easy and effective noninvasive approach within urban environments. Measurements were processed using the widely applied Horizontal-to-Vertical Spectral Ratio (HVSR) method, following the SESAME project (2004) guidelines. Their fundamental and dominant frequencies, fo and fd, respectively, were calculated and related to the iso-depth contours of the investigated area, as well as their corresponding amplitudes, Ao, and Ad. These experimental parameters and the HVSR curves were used to group all examined sites into classes with similar properties. This clustering provided a zonation map with four categories consisting of similar shapes and amplitudes, applicable to the city of Durres. This map can be utilized as a first level zonation of local site effects for the city. In addition, dynamic properties of soil profiles in selected sites were investigated and tested using 1D synthetic ambient noise data, based on the Hisada (1994, 1995) simulation method, and compared to experimental HVSRs in proximity to the selected sites. A comparison of the proposed four categories zonation map to the observed damage of the 26 November 2019, mainshock is attempted and evaluated. The four categories zonation map with similar expected local site effects proposed in this study can be used as a first level seismic microzonation of Durres. Undoubtedly, corrections for 2D/3D effects on ground shaking must be applied to sites lying in the edges of the Durres basin. [ABSTRACT FROM AUTHOR]