This paper presents an in-depth analysis of the Kopčić House, a significant example of modernist architecture in Sarajevo, Bosnia and Herzegovina, focusing on its structural-specific features and seismic performance. The Kopčić House embodies a confined masonry structure with innovative construction features, combining load-bearing masonry walls with reinforced concrete elements. This architectural approach was pioneering for its time, combining traditional construction methods with innovative materials and techniques. Detailed analysis using numerical modeling techniques, specifically 3D modeling with the 3Muri software (Vers.14.2.0.4), was conducted to assess the seismic resilience of the structure. The analysis considered different load distributions and eccentricities to comprehensively evaluate the building’s response to lateral forces. The findings of this research reveal the structural capacity and potential vulnerabilities of the Kopčić House when subjected to seismic events. While the building demonstrates inherent strength due to its confined masonry design, areas requiring structural strengthening were identified through numerical simulations. This study contributes to the broader understanding of confined masonry construction within the context of modernist architecture. By integrating historical research with advanced structural analysis, this work aims to bridge the gap between architectural heritage and contemporary engineering practices.

The 2020 earthquakes that hit the Croatian capital city Zagreb and Petrinja revealed the (un)preparedness of the country once exposed to strong earthquake motion. Three years after, numerous buildings out of 25,000 that have been heavily damaged and destroyed still have not been reconstructed. The effect of the earthquake was felt as well in the bordering cities and towns in Bosnia and Herzegovina (BIH). Seismic assessment of the existing buildings in BIH is done by individual researchers and there is no defined methodology not policy for such activities. This paper aims to present the work that has been done in this field up to now and to give guidelines for the further work that needs to be conducted. The starting point was the calculation of the earthquake risk for the entire Bosnia and Herzegovina based on the rapid assessment taking into account the vulnerability of buildings, seismic hazard, and population exposure. A more detailed assessment was conducted for the three largest cities in BIH, specifically Sarajevo, Banja Luka, and Tuzla. Typical residential masonry structures were identified, and detailed calculations were conducted, leading to the need for their strengthening. To have a more detailed picture much work has to be conducted.

PurposeThis paper aims to develop preliminary damage scenarios for unreinforced masonry buildings located in low to moderate seismic hazard areas in Algeria, taking into account the specific site effects.Design/methodology/approachThree soil types were considered in this analysis according to the definition of the Algerian seismic code (RPA99/2003). Peak ground acceleration values were assigned to each soil type issued from a probabilistic seismic hazard analysis (PSHA). To highlight the effect of soil conditions on the seismic vulnerability analysis of masonry buildings, a site vulnerability increment is carried out, and the macroseismic Risk-UE method has been adopted and applied by developing two main seismic scenarios according to both return periods of the PSHA, 100 and 475 years, respectively.FindingsBased on the preliminary results of rock site condition, it can be outlined that the significant damage obtained for different earthquake scenarios discovered a substantial worldwide seismic risk to the building stock of the study area. Once the site effect is integrated into the analysis, more high values of vulnerability indexes and expected damages are obtained. Moreover, it can be concluded that soft soil (S3) is a little bit more influential than stiff soil (S2) on the final vulnerability index compared to (S1). However, the difference between the soil effect S2 and S3 on the vulnerability index can be neglected.Research limitations/implicationsResearchers are encouraged to test the mechanical approaches for more detailed outcomes of a specific building analysis.Practical implicationsThis research proves to the Algerian decision-makers that due to the site effects and the vulnerability of the masonry buildings, an urgent intervention program is required even for existing buildings located in low to moderate seismic hazard areas.Originality/valueSeveral seismic vulnerability types of research have been conducted in Algeria for the unreinforced masonry buildings in moderate to high seismic areas in which generally the soil effect is neglected. In this context, this research paper proves that due to the site effects and the vulnerability of the masonry buildings, special attention is required even for existing buildings located in low to moderate seismic hazard areas. With this conclusion, the requirement of taking into account the soli effect in the high seismic areas is even more pronounced and should be conducted.

ABSTRACT The building stock in most historical urban areas in Algeria consists of old masonry buildings which are characterized by the rather high vulnerability. In that respect, to reduce the seismic risk there is a requirement for strategic urban planning and urban management policies. This paper focuses on the assessment of the seismic vulnerability using the RISK-UE methodology, namely the mechanical method LM2, which is adopted and applied to fit the Algerian urban features. In order to implement the RISK-UE LM2 methodology, an old urban center in Annaba city is chosen as a pilot area. Almost, the majority of the structures are unreinforced masonry buildings. In total 226 buildings were assessed, which are typical not only for this region but can be found in many other medium-sized Algerian urban environments. Three scenarios that take into account various values of the peak ground accelerations (PGA) are elaborated. Two scenarios use PGAs issued from an existing probabilistic seismic hazard analysis (PSHA) of Annaba city for 100 and 475 return periods. The third PGA for the last scenario is taken from the Algerian seismic code (RPA99/2003). In order to highlight the degree of vulnerability and risk of the studied masonry buildings, a comparison between the three seismic scenarios is presented in detail for each building’s typology. The obtained seismic vulnerability outcomes offer a great prospect to provide recommendations for making correct decisions to reduce the seismic risk and conduct adequate emergency planning in Algerian urban areas.

Minarets, tall structures, connected or not to the mosque attract attention due to their specific architectural features. Vulnerability to seismic damage has been witnessed throughout history on tall and slender structures after earthquake ground motions. In that respect, it is of the utmost importance to investigate the dynamic characteristics and resilience of historical stone minarets. This paper aims to provide the results of an on-site dynamic investigation of a stone minaret in Mostar and deliver its seismic assessment. The minaret is part of the Tabačica mosque built at the turn of the 16th and 17th century in the City of Mostar, Bosnia and Herzegovina. The on-site investigation comprised dynamic identification of the minaret by ambient vibration testing and qualitative estimation of the masonry wall by sonic pulse velocity testing. Besides the modal analysis a time-history analysis was performed by using the Applied Element Method (AEM), considered an appropriate tool for assessing the behavior of historic masonry structures. A good match is found between the first natural frequency obtained by the on-site investigation and the modal analysis which is a solid basis for further seismic assessment of the minaret as a slender tower-like structure. The concentration of stresses is observed at the transition zones.

Minarets are slender and tall structures that are built from different types of materials. Modern materials are also starting to be used in such structures with the recent developments in material technology. The seismic vulnerability and dynamic behavior of minarets can vary, depending on the material characteristics. Within this study’s scope, thirteen different material types used in minarets in Türkiye were chosen as variables. A sample minaret model was chosen as an example with nine different heights to reveal how material characteristic change affects seismic and dynamic behavior. Information and mechanical characteristics were given for all the material types. Natural fundamental periods, displacements, and base shear forces were attained from structural analyses for each selected material. The empirical period formula for each material is proposed using the obtained periods, depending on the different minaret heights taken into consideration. At the same time, fundamental natural periods for the first ten modes and 13 different types of materials used in the study were estimated with the established Artificial Neural Network (ANN) model. The real periods from the experimental analyses were compared with the values estimated by the ANN using fewer parameters, and 99% of the results were successful. In addition, time history analyses were used to evaluate the seismic performance of the minaret (three different materials were considered). In this specific case, the acceleration record from the 2011 Van (Eastern Turkiye) earthquake (Mw = 7.2) was taken into consideration. Performance levels were determined for the minaret according to the results obtained for each material. It has been concluded that material characteristics significantly affect the dynamic and seismic behavior of the minarets.