Albania Earthquake Research Articles

Seismic Performance of Reinforced Concrete Buildings with Joist and Wide-Beam Floors during the 26 November 2019 Albania Earthquake

Beams with width greater than their depth and depth equal to the depth of the slab (concealed wide beams) are widespread in Reinforced Concrete (RC) buildings in Albania. A large number of RC buildings with wide beams were hit by a strong Mw6.4 earthquake on 26 November 2019. The earthquake hit two of the most densely populated areas in Albania and caused widespread damage to these buildings. This paper aims to provide an updated view on the seismic performance of buildings with wide beams in light of the new field data following the 26 November 2019 Albania earthquake. To this end, a thorough literature review including experimental and field observations from past earthquakes is presented and data from field visits in Albania are described. It was found that damage to the joists and wide beams themselves was limited, even when the buildings suffered significant non-structural or structural damage in other elements as a result of the earthquake. A discussion on the behavior of wide beam–column frames based on nonlinear structural analyses and tests from the literature is presented. Furthermore, the implications of the results of the analysis for the seismic performance of RC buildings are discussed and confronted with observations from the 2019 Albania earthquake. Based on the literature review, further experimental research on wide beams with longer and more realistic span lengths is recommended.

Development in Fuzzy Logic-Based Rapid Visual Screening Method for Seismic Vulnerability Assessment of Buildings

In order to prevent possible loss of life and property, existing building stocks need to be assessed before an impending earthquake. Beyond the examination of large building stocks, rapid evaluation methods are required because the evaluation of even one building utilizing detailed vulnerability assessment methods is computationally expensive. Rapid visual screening (RVS) methods are used to screen and classify existing buildings in large building stocks in earthquake-prone zones prior to or after a catastrophic earthquake. Buildings are assessed using RVS procedures that take into consideration the distinctive features (such as irregularity, construction year, construction quality, and soil type) of each building, which each need to be considered separately. Substantially, studies have been presented to enhance conventional RVS methods in terms of truly identifying building safety levels by using computer algorithms (such as machine learning, fuzzy logic, and neural networks). This study outlines the background research that was conducted in order to establish the parameters for the development of a fuzzy logic-based soft rapid visual screening (S-RVS) method as an alternative to conventional RVS methods. In this investigation, rules, membership functions, transformation values, and defuzzification procedures were established by examining the data of 40 unreinforced masonries (URM) buildings acquired as a consequence of the 2019 Albania earthquake in order to construct a fuzzy logic-based S-RVS method.

Rapid Public Information and Situational Awareness After the November 26, 2019, Albania Earthquake: Lessons Learned From the LastQuake System

Rapid Public Information and Situational Awareness After the November 26, 2019, Albania Earthquake: Lessons Learned From the LastQuake System

Correction to: Performance of RC cast-in-place buildings during the November 26, 2019 Albania earthquake

Correction to: Performance of RC cast-in-place buildings during the November 26, 2019 Albania earthquake

Performance of RC cast-in-place buildings during the November 26, 2019 Albania earthquake

This paper documents performance of cast-in-place reinforced concrete (RC) buildings in the Durrës municipality during Albania earthquake of November 26, 2019 (MW 6.4). Both mid- and high-rise RC buildings were affected by the earthquake, experiencing structural and/or non-structural damage and even collapse in some cases. The authors performed a reconnaissance study after the earthquake and were involved in seismic assessment of buildings in the affected area. Besides the observations related to physical damage of RC buildings, the paper also presents results of a statistical analysis of damaged RC buildings in the Durrës municipality. The discussion in the paper is focused on damage patterns and failure mechanisms that are relevant for the seismic response of RC structures. Most common damage pattern observed after the earthquakes was related to masonry infill walls, which experienced damage and failure in some cases, and affected the performance of adjacent RC columns due to the infill/frame interaction. Taller RC framed buildings (10 storeys and higher) were expected to have RC shear walls; however, these walls were reportedly absent in the damaged buildings of this type. In some cases, masonry infill walls (instead of RC shear walls) were used in the elevator shaft areas, which resulted in inadequate seismic performance. A case study has been presented to illustrate seismic behaviour of mid-rise and high-rise cast-in-place RC buildings in the November 2019 earthquake, and is based on post-earthquake field observations and a detailed seismic assessment of two earthquake-damaged buildings. Finally, relevant lessons and recommendations are presented in light of the observed performance of RC buildings.

Damage assessments by International Engineers following the Albania earthquake of November 2019

Following earthquakes in populated areas there is need to assess damage to buildings and other structures. A challenge for the local authorities is to set up a system for coordination of potentially hundreds of assessors over several weeks or even months. The objectives of a Damage Assessment Coordination system are to protect people from potentially dangerous buildings and to facilitate the rapid return to medium-term/permanent accommodation and work. For large events, assessments generally require hundreds of assessors and many weeks for the initial life-safety assessments. In past events International Engineers have been dispatched to assist national Engineers in their efforts. This paper outlines key challenges in incorporating International Engineers into a national effort by reviewing literature of two recent earthquake responses and providing a detailed account of the damage assessment provided by International Engineers during the response to the November 2019 Albanian Earthquake. The authors responded to Albania and jointly set up and operated a new concept: Damage Assessment Coordination Centre (DACC). The DACC had two objectives: (1) Support the local authorities to setup their own effective system of Damage Assessment Coordination, and (2) Coordinate international teams to assist the local authority-led damage assessments. Between 1st - 18th December, 185 International Engineers from 18 countries were deployed alongside Albanian assessors, supporting the Albanian-led assessments, and directly conducting over 3200 assessments. This paper recommends that preplanning of a damage assessment coordination system based on 4 proposed categories would expedite the establishment and the effectiveness of a national system and the incorporation of International Engineers.

The Albania Earthquake of 2019: Causes of Damage to the Buildings and Its Social Consequences

On 26 November 2019, the city of Durres in Albania was hit by an earthquake measuring 6.3 on the Richter scale with an intensity of 8–9, killing 51 people in total. Some buildings were destroyed, causing fatalities, while many other buildings suffered serious damage but caused no fatalities. Many high-rise buildings up to 12 floors high sustained constructive and masonry damage. Most of the masonry damage was found in buildings built after 1991 and perceived by the general public to be safer. The damage to the residential high-rise buildings left many families homeless, and although approximately two years have passed since the quake, some of these families are still homeless. This study is based on 38 interviews with residents whose homes have become uninhabitable and with civil engineers who have worked in the construction sector. Additionally, 11 in-depth analyses that were carried out for 11 severely damaged objects were studied. This study aims to determine what caused the damage to these buildings. The causes ranged from unauthorised floor additions to lack of compliance with the best building codes during the design phase. It also shows the slow progress of reconstruction, particularly in the most severely damaged buildings. Furthermore, this protracted reconstruction period has led to social problems within families.

Damage and performance evaluation of masonry buildings constructed in 1970s during the 2019 Albania earthquakes

A Mw 6.4 earthquake hit the NW region of Albania on November 26, 2019, resulting in extensive damage to the civil structures in the broader area of Durrës city and its surroundings. According to the official statistics, it caused 51 death toll and ∼ 1.2 billion US dollars economic loses. This study investigates the seismic response of masonry buildings damaged during the earthquake. Four important typologies are selected to draw general conclusions from the performance analysis and damage assessment. A detailed field survey after the earthquake was conducted in Albanian territory to observe the impact on low and mid-rise buildings. Seven masonry buildings with 3 to 5 floors were chosen to represent the commonly constructed template designs. Mathematical models of each building were prepared in the light of experimental test results on the quality of structural wall components. Seismic displacement capacities of each building were estimated by pushover analysis. The significance of the findings was further explored by considering the inelastic response of a group of representative buildings during the 2019 Albania earthquake sequences. According to the analyses made, Near Collapse damage state may be reached at a PGA of 0.16 g for some type of buildings. At 0.26 g all considered buildings are expected to be either collapsed or at a near collapse stage. The expected PGA with a return period of 475 years is around 0.3 g and even reaches to 0.4 g in the region. Considering the analysis results, it can be said that decision makers should be aware of the catastrophic consequences of similar future events.

An early assessment of presence of probable post-traumatic stress disorder and its associated risk factors in a cohort of survivors of the 2019 Albania earthquake

An early assessment of presence of probable post-traumatic stress disorder and its associated risk factors in a cohort of survivors of the 2019 Albania earthquake

Correction to: Observations from the 26th November 2019 Albania earthquake: the earthquake engineering field investigation team (EEFIT) mission

Correction to: Bulletin of Earthquake Engineering (2021) 19:2013–2044 https://doi.org/10.1007/s10518-021-01062-8 The Editor-in-Chief alerted the authors that proper attribution needs to be given to below reference, which will be added the list of References. The figure legend for Fig. 1 should read as follows: Fig. 1 Albanian earthquake sequence of 2019 and visited locations during the EEFIT mission (EDSF active fault traces adapted from Basili et al. 2013)

Geodetic slip model of the November 26, 2019 Albania earthquake estimated from Sentinel-1 TOPS interferometry

This study uses Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR) data to investigate the source model of the 26 November 2019 Albania earthquake, the largest earthquake to hit the northwestern region of the country in the last century. The preferred InSAR-based coseismic slip model shows that the slip is distributed in a relatively narrow area and is located at a depth of ~11 km with a maximum amplitude of ~0.89 m. The estimated geodetic moment of this earthquake is 3.70 × 1018 Nm, with a shear modulus of 40 GPa, which is equivalent to Mw 6.31. The preferred slip model shows that this earthquake ruptured an east-dipping fault, namely the Shijak Fault wherein the primary slip mechanism is the dip-slip motion. Two-dimensional (2.5-D) surface displacement derived from three pairs of InSAR data is used to ensure the dip direction of the seismogenic fault responsible for the 2019 Albania earthquake. The result of 2.5-D displacement shows the dominance of the westward and uplift motion with a maximum amplitude of ~0.1 m. It indicates that the source fault dips to the east, confirming the result of inversion analysis.

Observations from the 26th November 2019 Albania earthquake: the earthquake engineering field investigation team (EEFIT) mission

On the 26th of November 2019, an earthquake of moment magnitude 6.4 struck the northwest region of Albania as the result of thrust faulting near the convergent boundary of the Africa and Eurasia plates causing widespread damage to buildings in the city of Durrës and the surrounding areas. Based on the official data from the national authorities, the earthquake caused 51 casualties and 985 million-euro losses, corresponding to 7.5% of the 2018 gross domestic product. This paper summarises field observations made by the Earthquake Engineering Field Investigation Team (EEFIT) after the event. The paper presents an overview of the seismological aspects of the earthquake together with a brief overview of the damage, official loss statistics and the estimated macro- and socio-economic consequences of the event. In addition, it provides a summary of the observed damage to both recent and historical buildings as well as the description of several case studies to illustrate the characteristic damage patterns observed in the main structural typologies of the Albanian building stock. These observations try to identify possible links between the observed damage patterns and the deficiencies in construction practice and use of inappropriate retrofit techniques for historical assets. As many severe damages were observed on modern buildings, this also allows the identification of some gaps and possible areas of development of the current seismic design code. In the end, the lessons learned from the field survey are resumed.

Performance of Prefabricated Large Panel Reinforced Concrete Buildings in the November 2019 Albania Earthquake

ABSTRACT The paper discusses the performance of prefabricated reinforced concrete (RC) buildings, known as large-panel buildings (LPE), that were affected by the November 26, 2019 Durrës, Albania earthquake (M 6.4). This was a common typology for multi-family housing in urban areas of Albania and neighbouring countries, e.g. ex-Yugoslavia, Romania, and Bulgaria, in the period from 1960 to 1990. The paper outlines the key structural and seismic features of LPE buildings in Albania and presents observations from a field survey of selected buildings at eight different localities within the earthquake-affected area. A new post-earthquake damage classification for LPE buildings has been proposed.

Seismogenic fault system of the M w 6.4 November 2019 Albania earthquake: new insights into the structural architecture and active tectonic setting of the outer Albanides

A seismic sequence that affected the Durrës region in late 2019 to early 2020 sheds new light on the structural architecture and active tectonic setting of the northern outer Albanides. Stress inversion analysis using focal mechanisms confirms that the area is dominated by ENE-trending horizontal maximum compression. The seismogenic sources consist mainly of ENE-dipping thrust faults roughly parallel to the coastline. The hypocentre distribution indicates that most of the earthquakes, including the M w 6.4 main shock, nucleated within the basement, with only some of the shallow aftershocks tending to cluster around the deeper portion of previously identified seismogenic structures within the sedimentary cover. Our results, unravelling for the first time the fundamental role of deeply rooted, crustal ramp-dominated thrusting in seismogenesis, imply a profound reconsideration of the seismotectonic setting of the region in terms of a correct assessment of seismic hazard in this densely populated area of Albania.

Performance of RC frames in 26.11.2019. Albania earthquake: Effects of irregularities and detailing

The collapse and damage of large number of buildings during the November 26, 2019 (Mw 6,4) Albania earthquake caused 51 fatalities and injuries to at least 910 people. Most of collapsed or heavily damaged buildings were RC frame buildings. Although RC frame system is considered as very ductile seismic force-resisting system, its behaviour during earthquake highly depends on: (1) regularity in plan and elevation, and (2) global and local ductility. Based on the authors' visit to the earthquake-affected area on behalf of the Serbian Association of Earthquake Engineering and observations of collapsed and damaged buildings, it was concluded that among main reasons for underperformance of these flexible systems were inadequate analysis of interaction between infill walls and RC frames and reinforcement detailing of RC members.

Rapid Public Information and Situational Awareness After the November 26, 2019, Albania Earthquake: Lessons Learned From the LastQuake System

The use of LastQuake information system, its app, the associated Twitter account and to a lesser extent the EMSC’s websites have been analysed for the 7-days following the Nov. 26, 2019 M6.4 Albania destructive earthquake to evaluate what can be improved and how crowdsourcing of information and monitoring of both use and absence of use of the app can contribute to rapid situational awareness. The mainshock and its numerous felt aftershocks triggered a strong public desire for information which in turn led to rapid and massive adoption of the LastQuake app by up to 5% of the country’s population. The constant flow of new app users created a stress test of the app’s crowdsourcing features and led to errors in the association of felt reports with their appropriate earthquake. However these errors had no identifiable impact supporting the conclusion that the curation mechanisms currently in place are efficient. The rapid succession of felt aftershocks contributed to these errors by making information related to the mainshock difficult to access within hours of its occurrence, especially for new users who were not attuned to the app. This revealed that prioritization of information within the app layout is lacking and is an important requirement during these kinds of events. LastQuake has been shown to be a powerful tool for rapid situational awareness. The possibility of damage was detected within 8 min of the mainshock earthquake by a lack of LastQuake app activity close to the epicenter. This possibility was then gradually strengthened as new data became available and was finally confirmed by the reception of the first geo-located pictures of structural damage and building collapse within 60-70 min. Direct exchanges on Twitter were appreciated by eyewitnesses and were reported to reduce their anxiety. Questions mainly focused on the possible evolution of the seismicity. Attempts to debunk prediction claims were difficult and we report on how this could be eased and possibly made more efficient by the use of a clear concise, pre-prepared statement in the local language explaining the state of scientific knowledge and the difference between prediction, early warning or forecasts.

Focal Mechanisms and Slip Models of Moderate Size Earthquakes in Albania and Adjacent Countries

The available data set of focal mechanisms in Albania and adjacent countries is enriched with the determination of source parameters for 27 earthquakes of moderate-size. The broad band waveforms recorded by the regional networks were used to do time-domain moment tensor inversion and also to invert for the slip distribution onto the fault plane for two events: one (11 February 2010) in the proximity of Lake Scutari (Albania-Montenegro borders) and the other (10 March 2010) in Serbia. Forward modelling is additionally applied, which incorporates synthetic Green's functions calculated for a 1D velocity model, to get a first-order evaluation of the distribution of strong ground shaking around the hypocenters. Forward modeling of strong ground shaking based on event-specific moment tensor and slip distribution indicates low levels of expected ground motion in accordance with observations. The new data confirm previous knowledge for the active tectonics of the region as for example the thrust/reverse faulting, along the low elevation areas of the foreland, and the sub-parallel normal faulting along the high elevation areas in the mountains.

Moderate earthquakes in Albania during 2009 and their associated seismogenic zones

In 2009, moderate earthquakes occurred in the Lezha-Ulqini and Lushnje-Elbasani-Dibra seismogenic zones in Albania. The earthquake of 21 August 2009 (ML 5.0) occurred in the Adriatic Sea near the town of Ulqini at the Albania-Montenegro border.The mainshock was located 9 km southeast of the epicentre of the 15 April 1979 Ms 7.1 earthquake that caused loss of life and considerable damage to buildings in Montenegro and Albania. The earthquake of 6 September 2009 (ML 5.4) occurred in Gjorica, at the eastern Albania- the former Yugoslav Republic of Macedonia (FYROM) border, south of the city of Peshkopia, Albania. The mainshock of the 6 September 2009 earthquake was located 12 km northeast of the epicentre of the 30 November 1967, Dibra/Debar earthquake (Ms=6.7) that caused loss of life and considerable damage to buildings in Albania and FYROM. For this analysis, the local and regional data concerning the epicentral locations, focal mechanisms, macroseismic data of the mainshocks, and their aftershock activity were used. Based on the focal mechanisms, the motion of the 21 August 2009 earthquakes was pure thrust with compressional axes NE-SW, and the 6 September 2009 earthquake occurred on a normal fault with a NW-SE strike direction of tensional stress. The region affected by the August 2009 sequence, together with the seismogenic region of the 1979 Ulqini event, forms a roughly NW-SEtrending active seismotectonic zone in western Albania and continues through southern Montenegro. The region affected by the September 2009 sequence, together with the seismogenic region of the 1967 Dibra event, forms a roughly NE−SW-trending active seismotectonic zone in eastern Albania that continues in the western FYROM. Both zones present a threat to the nearby urban areas in Albania, Montenegro and the FYROM.

Catalogue of ML≥3.0 earthquakes in Albania from 1976 to 1995 and distribution of seismic energy released

The construction of a catalogue of earthquakes in Albania with M L≥3.0 is described for the period 1976–1995. Phase readings from 13 stations in the Albanian Seismological Network and some nearby stations are employed. Some preliminary findings on recent seismicity in the country are presented. A b-value that is very near to long-term value of this parameter is found. Only in a very few cases do hypocentral depths exceed 40 km. There are about 400 felt earthquakes in the catalogue and of these 25 have caused damage. On the basis of the whole catalogue, and by calculating the seismic energy released for 220 cells covering the whole of Albania, an overview of the distribution of seismic energy and cumulative magnitudes is provided. Seven zones with high energy release for the period 1976–1995 are revealed. The cumulative magnitude in these zones is more than 5.0. This analysis provides insight for a better understanding of the seismicity of Albania and may assist in hazard assessments.

5520904 Calcium/oxyanion-containing particles with a polymerical alkoxy coating for use in medical diagnostic imaging

On November 30, 1967, a strong earthquake of magnitude M = 6.6 struck the Dibra region, eastern Albania, causing considerable loss of human life and grave material damage both in the territory of Albania and that of Yugoslavia.The object of this study is to describe the effects of this earthquake on landscape and buildings, as well as to define its macroseismic field. The study further deals with some features of the aftershocks of M ⩾ 4.0 distributed in time and space, the aftershock activity and the focal-mechanism solution of the main event.From the study of the macroseismic field of this earthquake and its fault, which extends over 10 km in a 40° northeasterly direction, from the distribution of aftershocks in space and the focal-mechanism solution of this earthquake, the conclusion has been reached that this event is connected with the Vlora—Dibra seismogenic belt.The authors have mentioned the existence of this traverse belt as early as 1969 (Sulstarova and Koçiaj, 1969). The existence of this belt is also shown by the chronological and geographical distribution of some strong earthquakes in Albania in the period 1800–1967 (their macroseismic field and the position of their epicentres), and by the focal-mechanism solutions of some of these earthquakes. The Vlora—Elbasan—Dibra transverse seismogenic belt continues for several hundred kilometres northeast and southwest beyond the territory of Albania.