Classification of residential building stock in Serbia

Developing a classification system (taxonomy) for buildings is a critical step for seismic risk assessment studies. Such a system can be used to characterize a building portfolio within urban/rural settlements or building stock for the entire country. Serbia is located in a region characterized by a moderate seismic hazard. In the last century, 10 earthquakes of magnitude 5.0 and higher occurred in Serbia, the strongest (M 6.0) in 1922. The strongest earthquake in the 21st century (Mw 5.5), with an epicenter close to Kraljevo, occurred in November 2010 and caused significant damage to residential buildings. In 2019, members of the Serbian Association for Earthquake Engineering (SUZI-SAEE) contributed to the SERA project and its goal to develop a seismic risk model for Europe. A taxonomy of residential buildings in Serbia was developed based on previous national and regional building stock studies. The proposed taxonomy includes the Lateral Load-Resisting System (LLRS) (e.g., wall, frame, dual wall-frame system) and material of the LLRS (e.g., masonry, concrete, wood) as the main attributes. The type of floor diaphragm (rigid or flexible) has been specified only for masonry typologies with unreinforced masonry walls, while building height and date of construction have been implicitly considered. According to the proposed taxonomy, there are 9 residential building typologies in Serbia; out of those, 5 typologies are related to masonry structures, 3 are related to RC structures, and one is related to wood structures. This paper describes the proposed taxonomy and outlines the characteristic features of different building typologies and their relevance for estimating seismic vulnerability and risk. A comparison of the proposed taxonomy for Serbia and published taxonomies for Croatia is also presented

Residential Building Stock in Serbia: Classification and Vulnerability for Seismic Risk Studies

Regional seismic risk assessment is necessary for designing effective seismic risk mitigation measures. In general, such risk assessment studies consist of three components: hazard, vulnerability, and exposure modelling. This paper lays the foundations for regional seismic risk assessment of the residential building stock in Serbia and addresses each of the three seismic risk assessment components, either by reviewing the existing or proposing novel models. First, a review of seismic hazard models and seismic design codes used in Serbia in the past 70 years was presented. Next, an overview of Serbia’s population metrics and historical development of Serbian’s residential building stock was presented to provide the context for the exposure model. Furthermore, the paper proposed a novel building classification for Serbia's residential building stock, which is based on the existing building taxonomies, but it has been adapted to account for the local building characteristics. Building damage patterns reported in past earthquakes in Serbia and neighbouring countries were reviewed as a basis for damage classification pertaining to building typologies included in the proposed classification. Finally, the results of a preliminary vulnerability model were presented in the form of expert-based fragility functions derived for buildings typical of Serbia's residential building stock

Petrinja, Croatia December 29, 2020, Mw 6.4 Earthquake Joint Reconnaissance Report (JRR)

On December 29, 2020 a magnitude 6.4 earthquake occurred in the Sisak-Moslavina county of Croatia. The earthquake occurred along the Popusko-Petrinja strike slip fault within the Eurasia plate at a depth of 10 km with an epicenter at 45.422°N 16.255°E, three kilometers (km) west-southwest of the city of Petrinja. The maximum intensity of the earthquake was VII (severe) on the Modified Mercalli Intensity (MMI) scale and VIII (heavily damaging) to IX (destructive) on the European Macroseismic Scale (EMS). Due to the earthquake and resulting damage, there were seven fatalities, 26 people were injured, and many hundreds of people were displaced from their homes. The most affected city was Petrinja, but severe damage also occurred in Sisak, Dvor, Glina, Topusko, as well as in Croatia’s capital Zagreb, located approximately 50 km northwest of the epicenter. Damage was also reported in neighboring countries, including Slovenia, located north of Croatia, and Bosnia and Herzegovina, located south of this region of Croatia. The purpose of this post-earthquake reconnaissance report is to provide, within a few days of the earthquake, an overview of the hazard characteristics and to summarize preliminary reports of damage to buildings, bridges, roads, and other infrastructure. Moreover, key findings are also summarized with regard to geotechnical failures that include liquefaction, lateral spreading, landslides, sinkholes and damage to the extended levee system along the Kupa, Odra and Sava rivers