3rd Croatian Conference on Earthquake Engineering 3CroCEE

Earthquakes pose a significant threat to the life safety and well-being of a large portion of the world’s population. The effects of sedimentary basins on infrastructure damage have been observed in numerous earthquakes that have occurred in the past few of decades. The United States Geologic Survey (USGS) incorporated basin effects into the development of the recent National Seismic Hazard...

The seismic vulnerability assessment of the diverse categories of buildings found across building stocks requires specific methodologies that can capture the wide range of standards, regulations, construction practices, architectural layouts, earthquake design scenarios, and available knowledge. Previous vulnerability models have employed varying assessment approaches, building taxonomies,...

This paper provides detailed investigation of the methodologies developed for seismic vulnerability assessment in the area. Empirical, analytical, and hybrid approaches that have been regionally developed and applied are summarized and their similarities and differences are discussed. Having in mind the parallels in existing structural archetypes in the region (N. Macedonia, Serbia, Bosnia and...

Seismic vulnerability assessment is a comprehensive process that involves evaluating the susceptibility of structures to potential damage or failure during seismic events. This assessment is crucial for understanding and mitigating the impact of earthquakes on structures. Still, it is necessary to emphasize that vulnerability assessment is not a singular procedure: it varies based on the scale...

Seismic design and assessment of structures hinge on accurately quantifying the non-linear behaviour of various structural and non-structural elements within the built environment. Experimental testing has become a cornerstone of earthquake engineering, providing invaluable insights into key structural behaviours that can be either designed for or mitigated against.

This paper presents...

In many countries, such as Montenegro, numerous existing reinforced concrete (RC) buildings were designed and built before the adoption of modern seismic codes. These buildings make up a significant portion of Montenegro's RC building stock, making their assessment, retrofitting, and strengthening an urgent research topic. This shortcoming because of insufficient transverse reinforcement, poor...

This study presents a comprehensive analysis of strong ground motion data acquired to better explain the extensive damage observed after the February 6th, 2023, Kahramanmaras, SE Turkey earthquakes (Mw 7.8 and Mw 7.6). As spectrum intensity values computed using response spectra of a ground motion are closely correlated with building damage, special emphasis is given on some engineering...

Infilled structures are the most used type of structures in seismic-prone countries. Masonry infills are the most vulnerable part of these structures, even under medium-intensity earthquakes; hence, developing systems to prevent their failure to protect goods and human lives is crucial. Since current design codes are very advanced in reinforced concrete structures designs and there has been...

The structural behavior of reinforced concrete (RC) structures with and without infill is investigated in this work under axial and horizontal loading scenarios. Using sophisticated software and micro modelling approaches, the structural performance of RC frames of various lengths both bare and infilled is assessed, with a focus on rigidity, ductility, and load-bearing capacity. The RC frames...

An effective seismic risk assessment of building stock is crucial for informing stakeholders about potential issues and enhancing community resilience. Recently, a parametric pushover curve model was introduced, enabling the estimation of building-specific pushover curves and fragility functions even with a low level of knowledge about the building. The model estimates a trilinear pushover...

After an earthquake, the availability of transport corridors must be guaranteed to allow the evacuation of the population and the unhindered passage of rescue vehicles. Bridges are crucial in any transport network and can be damaged, partially or completely collapsed during an earthquake. On the other hand, in such circumstances, it is important to ensure fast and safe passage of people and...

The second-generation of Eurocode 8 (EC8) has reached an advanced stage of development and some validations have already been made. With reference to the seismic assessment of existing masonry buildings, basically the same methods proposed for the design of new structures are indicated: linear static analysis, and nonlinear static analysis. Even if these methods are already in use within some...

The interaction between urban tramway infrastructure and earthquake-damaged buildings presents a significant challenge for structural engineers and urban planners, particularly in densely populated, heritage-rich city centers. This paper examines the impact of vibrations induced by tram traffic on the structural integrity of earthquake-damaged buildings, through a case study of a historical...

Assessment of mechanical properties of unreinforced stone masonry depends on the material used and the construction techniques applied. In this paper we explore the mechanical properties of stone masonry components on a case study - a more than 200-year-old historical building near Rijeka, which is currently being renovated and repurposed, as part of the ongoing research project on stone...

The Byzantine civilization is one of the longest-lived cultures, well known by the large number of religious buildings, which today represent part of the world cultural heritage. Byzantine churches are great part of North Macedonia’s tangible heritage, as one of the most valuable and numerous medieval monuments, with exceptional architectural and artistic values. Several characteristic...

The deterioration of old masonry structures, particularly from the Middle Ages, poses significant challenges due to material degradation and structural deficiencies. This study focuses on assessing and strengthening a traditional stone masonry "Kulla," addressing the need to preserve its historical character while improving its structural performance to meet modern building codes. The research...

An N-degree-of-freedom structure can be represented by using N single-degree-of-freedom modal sticks/oscillators, which form an N-dimensional modal space. Because each modal stick represents a modal equation of motion, we always take it for granted that a modal stick is one-dimensional. This paper shows that a modal equation of motion could be multi-dimensional. Accordingly, the corresponding...

Dual systems that combine moment-resisting frames with innovative replaceable bracing systems offer significant advantages over conventional solutions. The key benefits of these systems include energy dissipation at specific locations and a re-centring capability, which substantially reduces repair costs. However, the design of such systems must meet specific requirements, such as using higher...

With the introduction of 3D graphic representation to improve workflows, communications, collaborations, and data exchange among all members involved in the project, the BIM (Building Information Modeling) methodology is completely transforming the structural industry. In general, BIM is fundamentally based on an information-sharing methodology among all stakeholders, implemented throughout...

With the significant advancements in computational power over recent decades, nonlinear response history analysis has become more prevalent in seismic design and assessment. A critical step in these applications is the selection and scaling of appropriate ground motion records. However, state-of-the-art record selection procedures are rarely employed by engineers due to the lack of...

Strong earthquakes are among the natural hazards with most destructive potential to life and property. Their negative effects must be adequately addressed allowing the communities to withstand, respond and recover from seismic events. Common mitigation measures include enforcement of seismic codes, land-use planning and strengthening of the existing structures. The seismic risk assessment...

Seismic risk assessment in Montenegro has been a critical concern since the devastating earthquake of 1979, which spurred initial studies for the country's spatial planning. In response, significant efforts were made to mitigate seismic risks and regulate the construction of earthquake-resistant structures. Early vulnerability studies were based on damage observations from the 1979 earthquake....

QuakeSafe is a transformative initiative, supported by UNESCO and funded by Huawei, aimed at deepening students' understanding of earthquake engineering and its implications for safety and sustainability through an innovative educational model. Implemented by the Institute of Earthquake Engineering and Engineering Seismology (UKIM IZIIS), this project utilizes specialized expertise to create...

Retaining cantilever walls are typically designed under drained conditions, assuming that proper drainage is implemented, correctly constructed, and functions throughout the structure's lifespan. However, when appropriate drainage cannot be constructed—such as in walls that cut into and retain a natural slope, where the wall is built adjacent to nearly vertical excavated soil, designers...

Modular construction has been increasingly used worldwide due to its fast assembly, cost-effectiveness, and sustainability; however, the performance of these structures in seismic-prone regions remains a significant engineering challenge.
The seismic behavior of modular buildings varies significantly, depending on the configuration of prefabricated modules and their intra- and...

This research investigates seismic risk assessment for bridge structures using a combination of conventional and next-generation intensity measures (IMs). The study focuses on simplified bridge models, characteristic of European construction, and explores the efficacy of multiple IMs, including spectral acceleration (Sa), average spectral acceleration (Sa_avg), and filtered...

As urban areas become increasingly dense, the vertical extension of existing structures has gained importance, especially in seismically active regions. The challenge is more pronounced for older buildings designed with minimal or no seismic provisions. Light frame timber systems are often preferred for vertical extensions due to their low mass, which minimizes additional seismic forces on the...

ABSTRACT
The focus of the research in this paper is Quasi-static tests on RC building columns strengthened with CFRP (Carbon Fiber Reinforced Polymers). To present the possibilities and the benefits of use of these materials, laboratory research for definition of the characteristics and experimental investigations of RC columns strengthened by CFRP by variation of concrete class,...

The existing seismic design codes consider bi-directional effects by applying the square root sum of squares (SRSS) or the percentage rule; the latter simplified way of design is commonly employed by accounting for the 100% contribution in the assumed principal direction plus 30% or 40% other direction’s contribution. Although the potential reasons of widespread building damage and collapses...

In recent years, advancements in employee safety protocols within production facilities have been steadily progressing. However, seismic events pose significant risks to production facilities, potentially disrupting operations, causing structural damage, and endangering the safety of employes. Such a scenario occurred in January 2022, when the Florina earthquake (M5.3) struck an industrial...

Ground motion models (GMMs) are the key element of probabilistic seismic hazard assessment (PSHA). These models predict an earthquake ground motion intensity measure as a function of some independent variables that represent the earthquake source, path and site effects. The latter one can substantially influence the PSHA results since they are critical factors affecting the amplitude,...

The purpose of this paper is to provide clarification to individuals attempting to create models for seismic exposure as well as seismic vulnerability and risk, based on the seismic lateral loads established by the Yugoslavian seismic design codes. The particular focus of the research are the JUS 39/64 and JUS 31/81 seismic design codes, since they were active codes for a significant period of...

In the last few decades externally bonded FRP strips and sheets have been the most commonly used technique for strengthening of RC structures and bridges. The fact that FRP does not corrode and good mechanical performance have made this material very popular to use. Prior to design and application of FRP strengthening, it is of great interest for design engineers to evaluate condition of...

In the initial stages of construction design, precisely defining the loads that a structure must support is of utmost importance. While structures are generally designed to handle live loads effectively, they must also be capable of accommodating other types of loads. The dominant types of loads that a construction must withstand can differ based on the materials used and the type of...

Earthquakes pose a significant threat to roads and infrastructure facilities. The collapse and damage of poles along roads due to earthquakes can pose a danger to road users and an obstacle to rescue services. The paper analyzes the influence of the material of construction and the type of pole foundation on the behavior and damage of poles during an earthquake. The paper first presents the...

Seismic risk perception can be considered as critical factor related to citizens behavior during earthquake public risk perceptions had been surveyed in Banja Luka, one of the most earthquake prone risk exposed city in Bosnia and Hercegovina. This study aims to identify various factors influencing people’s perceptions of earthquake risk.
This paper presents quantitative research results...

Post-earthquake damage assessment is a critical process carried out by engineers and emergency responders to evaluate structural safety and guide decision-making in the aftermath of seismic events. Traditional training methods face limitations such as restricted access to real damaged structures, safety risks, and high logistical costs. This paper presents the progress of an ongoing project...

This paper examines the impact of what is arguably the most critical connection in a steel building: the column base connections under earthquake loads. Failure of this connection can lead to partial or even complete structural collapse. The rotational stiffness of these connections—whether they are considered fixed or pinned—significantly influences the seismic response of steel buildings....

The rock slope stability in seismically active regions is a critical aspect for safe and sustainable quarrying. This study investigates the effect of seismic loading on the stability of a dolomite quarry, integrating traditional analytical methods with advanced two-dimensional finite element models. The site, located near a historically active earthquake zone, provides an ideal environment to...

For high-rise buildings, reinforced concrete (RC) shear walls have emerged as a preferred structural element due to their significant contributions to global lateral strength, stiffness, and ductility. The lateral stiffness RC structural walls provide to the building system effectively mitigates structural and non-structural damage by limiting excessive deformation. Therefore, accurately...

Major earthquakes cause displacements primarily due to seismic accelerations, which affect the frictional strength of underlying soils. It is anticipated that the total displacement of sloped soils in earthfill dams triggered by an earthquake is influenced by the magnitude and frequency of the seismic event. This underscores the importance of numerical simulations that incorporate a broader...

The EMERGE project initiative aims to enhance regional disaster management by developing scenario-based and near real-time seismic and landslide risk evaluations. This will enable rapid needs assessments to guide resource allocation at national and regional levels. Building on the achievements of the UCPM CRISIS project, EMERGE seeks to expand CRISIS platform into a tool for rapid needs...

This paper evaluates the seismic resistance and vulnerability of an existing unreinforced masonry (URM) building in Zagreb's Folnegovićevo neighborhood. The building with potentially low seismic resistance was erected in the 60s, a period characterized by the introduction of the first seismic code in practice. It has a rectangular plan 36.9 m x 10.7 m and consists of a basement, a ground floor...

The computationally intensive nature of performance-based earthquake engineering (PBEE), particularly when implemented through detailed component-based approaches such as FEMA P-58, has limited its use primarily to academic research and specific studies. A more streamlined alternative, favoured by practitioners, employs story loss functions (SLFs) to estimate expected monetary loss per story...

This paper presents a comparative analysis of seismic risk assessment frameworks within the context of urban disaster risk management (DRM) in European transnational borders, as part of the BORIS2 project. BORIS2 project aims to enhance multi-risk assessment methodologies for emergency conditions at urban scales across country borders in Europe. The project seeks to establish a replicable...

Soils' local geological and geotechnical properties may lead to sharp variations of seismic shaking and structural damage at small distances. These so-called seismic site effects significantly impact the amplitude and frequency components of the ground motion. Key site effect parameters are the shear wave velocity of soils (Vs), indicating the material stiffness, and the fundamental vibration...

Today, the use of energy-dissipating systems such as yielding metal damper in structures can improve the seismic performance of structures. One of the characteristics of metal-yielding dampers is the ability to dissipate high energy and increase the ductility of the structural system, which can improve the ductility and energy absorption characteristics of the metal frame equipped with braces...

Assessing existing bridges is an important task in the sustainable management of infrastructure, particularly for those structures that have been in service for extended periods and lack comprehensive technical documentation. In fact, due to the old age of a large part of the infrastructure assets and the deteriorating conditions affecting the structural elements, their safety with respect to...

The assessment of the condition of existing bridges is of great importance, particularly for bridge structures that have been in operation for a long time and for which no adequate technical documentation exists. The behavior and condition of these bridges change over time, making it necessary to perform specific experimental tests and additional analyses to determine their actual load-bearing...

In this paper are presented original results obtained from the realized well targeted laboratory tests of nonlinear response of the constructed large-scale prototype models of circular RC bridge piers under realistically simulated earthquake-like cyclic bending and different levels of the induced axial loads.
Considering the obtained detailed results from the integral experimental...

After the last two major earthquakes that shook northwestern Croatia in 2020, field inspections of structures were carried out according to a previously defined methodology, which was implemented through a software application. However, this methodology and application was limited only to typical (multi)storey buildings made of masonry and/or reinforced concrete. A similar approach is now...

Heavy rainfall-induced floods, landslides and rockfall that befell Jablanica and Buturović polje regions in Bosnia and Herzegovina in October of 2024 caused widespread damage to buildings, roads, bridges, electrical, water supply and gas distribution networks, along with dozens of victims and hundreds of displaced people. Urban search and rescue operations started immediately, with...

Exposure assessment is paramount for disaster risk reduction, but there are still many open challenges to develop high-resolution, up-to-date reliable exposure models. Existing research efforts are focused on developing global-scale high-resolution exposure layers on the building level and enriching them with local features collected using different methods. Depending on the hazard at stake,...

In seismic design and assessment, it is often assumed that the seismic resistance of the structure remains constant over time, although it is subject to deterioration processes. However, structure exposure to its environment and local climate lead to several degradation mechanisms, which impact structure durability and load-bearing capacity. By neglecting the influence of the environment and...

The seismic performance of building structures is governed by the lateral stiffness which is provided by the geometrical and material characteristics of their structural elements and their arrangement in plan and elevation. In general, the procedure for designing the structures to withstand the code-prescribed lateral loads is quite straightforward. However, the performance of the building...

The official adoption of Eurocode standards in North Macedonia, compared to developed EU countries, was only in recent years, leaving a significant gap that needs to be tackled. The new generation of Eurocode standards is posing demands to seismic hazard assessment’s outputs to use the most updated seismic hazard models, which will be crucial for the development of national annexes. To improve...

Seismic risk encompasses the potential damage and losses resulting from earthquake events. Reliable risk assessment, apart from hazard assessment, requires precise and, as much as possible, accurate definitions of both the exposure and vulnerability models, as these components are interdependent and influence one another. This study focuses on developing an exposure model for the Aerodrom...

The search for environmentally friendly building materials has led to the development of dowel laminated timber (DLT), a product in which sawn timber boards are laminated using hardwood dowels. The dowels in DLT reduce the need for metal fasteners and synthetic adhesives. However, the application of DLT beams is challenged by the relatively low bending stiffness resulting from the low...

Masonry infills are used as outer and inner partitions in reinforced concrete (RC) frame buildings. Although regarded as non-structural elements, masonry infills are activated under seismic actions. Because of this activation, masonry infills experience life-threatening damage. Moreover, they affect the seismic response of the whole RC frame structure, as they modify the dynamic...

The structural stability of many buildings, including important institutions like hospitals, was seriously affected following the 2019 earthquake in Albania. This paper presents a detailed case study of the retrofitting project undertaken for a hospital in Albania, which experienced significant damage during the earthquake. The primary objective of this project was to restore and improve the...

This paper presents an analysis of the behaviour of a wooden building and its dynamic parameters, considering different methods of modelling the connections between elements, with a focus on the structural elements that are part of the horizontal load-bearing system. The building's structural elements are made of GLT, CLT, and LVL components, with a unique horizontal load-bearing structure...

To establish a connection with structural vulnerability, ground motions generate intricate datasets distinguished by various properties.
The objective of the investigation is to evaluate the impact of specific seismic record properties on the nonlinear structural response of buildings, with the ultimate goal of determining the characteristics that have the most significant effect on...

This study examines the influence of code-prescribed methodologies for ground motion record selection on the higher-mode response of structures. Specifically, it compares two conceptually different target spectra: the Uniform Hazard Spectrum (UHS) and the Conditional Spectrum (CS). Using shear wall buildings designed following Eurocode 8 (EC8) response spectrum analysis, we analyse the...

In earthquake-prone areas, soil–structure interaction (SSI) may play a key role in ensuring structural safety. This study investigates the effects of SSI on the seismic response of a six-storey reinforced concrete (RC) frame building, using guidelines from American codes and Eurocode 8 for soil types B and C. The analysis compares the building's behavior under various soil conditions and...

As part of the tangible cultural heritage, historic buildings hold great importance for today’s societies. These are buildings that have persisted for hundreds or thousands of years as visible witnesses of the past generations and their traditions, and as such deserve special attention and treatment.
A particular challenge is the protection of historical buildings located in seismic regions,...

Assessing earthquake risk in regions with moderate to high seismic hazard, such as parts of Republic of North Macedonia, is essential for effective risk management and mitigation strategies. Comprehensive risk assessments enable predictions about where high-intensity earthquakes are most likely to occur and what their potential impacts might be. In the frame of Study for Natural and technical...

The recent seismic activity in Croatia has inflicted significant damage on numerous buildings, with masonry structures being especially vulnerable. For the effective rehabilitation and restoration of these structures, it is critical to assess key mechanical properties such as the modulus of elasticity, compressive strength, tensile strength, and shear strength. Conventional methods for...

In everyday engineering calculations, walls in masonry structures are typically analyzed as isolated from the rest of the structure. The corresponding gravitational load is determined, and the horizontal load is applied to the wall, assuming that floors are rigid within their plane and transfer horizontal loads according to the stiffness of the walls at the building's base. The wall's bearing...

The understanding of earthquake occurrence patterns and their implications for short-term increases in seismic hazard and risk is crucial during ongoing seismic crises. This understanding enables informed decision-making by civil protection and governmental agencies. Aftershocks exacerbate seismic hazards by striking already weakened structures and generating strong ground motions, which...

A vast majority of experimental results have been accumulated to assess the shear modulus of various soils at very small levels of strains., so called small strain modulus or maximum shear modulus, Gmax. The cyclic triaxial test procedure due to overriding popularity in recent decades has become widely used methods for measuring modulus and damping. For fine granular soil materials Cyclic...

The landslide is the movement of soil and rocks down a slope, as a result of the loss of shear strength in the material that builds the slope. Although various human activities increase the risk of landslides, the most common causes for the loss of shear strength are geological and morphological. Thus, natural triggers for landslides can be the characteristics of the soil and rocks that build...

The assessment of liquefaction potential is critical in regions subject to seismic activity, as it can cause significant damage to buildings and infrastructure. However, the reliability of liquefaction potential evaluations is highly dependent on the assessment methods employed and the number of representative investigations conducted. This issue is particularly pertinent when assessing linear...

Abstract: Ground motion models - GMM-s for epicentral zone have been developed based on records of occurred shallow earthquakes obtained on soil type - rock, epicentral distances ., focal depths and local magnitude M = 3.9 - 6.1. Spectral acceleration - SA has been investigated for damping of 5% and for 221 models of a single-degree-of-freedom system with natural period ranging from 0.05 to...

Confined masonry (CM) technology is extensively employed in many parts of the world for the construction of residential buildings due to its improved seismic performance compared to the vulnerable unreinforced masonry (URM). This study focuses on the numerical simulation of seismic response of CM walls and a three-storey model of a CM building using Equivalent Strut Models (ESM) in OpenSees...

Technological development in construction has brought significant advances in the application of materials, particularly composites such as fiber-reinforced polymers (FRP) and textile-reinforced concrete (TRC). These materials have become widely used due to their excellent mechanical properties, including high strength and low weight, making them suitable for the refurbishment of damaged...

The objective of this study is to estimate the high-frequency decay parameter – kappa (κ) for stations installed on rock (according to EC8) for North Macedonia region.
Kappa characterizes the attenuation of ground motion at high frequencies, more precisely defines the rate of decrease of the acceleration amplitude spectrum. At higher frequencies ground motions on rock may be larger than...

The paper presents an overview of the new provisions of the second generation of the EN 1998 standards dedicated to design of bridges for earthquake resistance based on available phase of development of standards. Main document Eurocode 8 – Design of structures for earthquake resistance – Part 2: Bridges (FprEN 1998-2:2024) is analysed in relation to the introductory Part 1-1: General rules...

Nonlinear behavior of contraction joints in arch dams, such as joint opening and sliding caused by hydrostatic pressure and temperature variations, can affect the dam’s serviceability. Furthermore, strong seismic events can additionally alter the response in dynamic conditions, impacting the natural period and stress redistribution in the arches and cantilevers. In order to enhance structural...

Nonlinear behavior of contraction joints in arch dams, such as joint opening and sliding caused by hydrostatic pressure and temperature variations, can affect the dam’s serviceability. Furthermore, strong seismic events can additionally alter the response in dynamic conditions, impacting the natural period and stress redistribution in the arches and cantilevers. In order to enhance structural...

This study presents a numerical validation of experimental results on masonry wallets using the Applied Element Method (AEM). Due to their historical nature, masonry structures are highly relevant in modern construction; however, they normally pose certain challenges regarding structural analysis because of their composite nature and nonlinear behaviour. While experimental investigations...

One of the main challenges of implementing the performance-based earthquake engineering framework and computing risk and associated consequences on a regional scale is incorporating structure-to-structure damage correlation in the analysis. This correlation relates to the expected damage between different structures in a region, considering they were likely built with similar characteristics,...

Reducing the degree of freedoms of building models significantly decreases the computational costs in time consuming structural engineering problems like dynamic analysis of structures, nonlinear analysis or any optimal design of structural systems. In this study, the finite element models of 3- and 9-story benchmark steel buildings with numerous degrees of freedoms are simplified to 3- and...

Iceland is one of the northern European countries with the highest seismic activity. The strongest earthquakes take place on two large transform faults, one of which is the densely populated South Iceland Seismic Zone (SISZ), characterized by its unique North-South aligned bookshelf dextral strike-slip faults that are responsible for the long-term release of tectonic strain across the zone....

The medieval town of Ston in southern Dalmatia (Croatia) has experienced several significant earthquakes since the mid-19th century, notably the ones in 1850 and 1996. While the macroseismic parameters as well as classification of damage to buildings in Ston related to the 1996 event are available from previous studies, the 1850 earthquake has only recently undergone detailed macroseismic...

The world has witnessed widespread damages and losses suffered by precious cultural heritage structures during recent earthquakes e,g. Emilia-Romagna, Italy 2012; Central Italy 2016; Turkey /Syria 2023; Morocco 2023; Tohoku, Japan 2011; Puebla, Mexico 2017; Nepal 2015; Christchurch, New Zealand 2011; Iran 2017, among others. Based on traditional surveys and reconnaissance using 3D...

The following paper focuses on the conducted performance-based analyses of 8 representative reinforced concrete frame structures. These structures encompass a range of stories, including 2, 3, 5, and 7, and feature varying bay numbers of 3 and 4. The frames are designed to represent the central frame of a reinforced concrete spatial frame structure. The RC frame structures are designed...

Seismic risk assessment is crucial for mitigation of strong earthquakes’ effects on communities since it offers a comprehensive framework for minimizing damage, casualties, and economic losses. This can be accomplished through designing earthquake-resistant structures, retrofitting the existing buildings, economic resilience, urban planning, and public education. One of the key elements of...

Building codes on earthquake-resistant design, construction, and retrofitting are being improved based on observations of building performance during strong earthquakes, with the aim of mitigating earthquake risk in proportion to the corresponding hazard, as highlighted in recent findings from the SeisRICHerCRO Croatian Science Foundation Research Project IP-2020-02-3531. In the Republic of...

The Zagreb settlements of Markuševec and Čučerje were significantly affected by the 2020 Zagreb earthquake, and over the past four years have been undergoing a process of renewal both in technical terms, as well as socio-demographically. The analysis of the post-earthquake renovation in these settlement was carried out by qualitative methodology and semi-structured interviews. They were...

Under seismic and gravity loading, existing unreinforced masonry (URM) cultural heritage buildings are vulnerable and prone to damage. With careful calibration and thorough validation, credible results can be obtained from the numerical tools, but this process requires reliable experimental data. Therefore, various blind prediction contests have been held recently. For example, a blind...

The Gründerzeit houses in Vienna, which were built between 1948 and 1918, are an essential part of the Viennese building infrastructure with a number of approx. 30,000. Since 1992, the masonry properties of over 200 buildings with over 2,000 test points have been determined and evaluated by the authors. These were determined in the course of the engineering findings in order to carry out the...

Presented in this paper is an innovative system efficient for seismic protection of sensitive infill in RC frame buildings created with upgrading of isolated buildings with developed specific uniform SB devices. Capability of the new seismic protection system of masonry infilled frame buildings was fully demonstrated with the conducted extensive seismic shaking table tests of large-scale...

The increasing spread of timber as structural material strongly seeks for deeper investigations concerning its behaviour, in static and, even more, in cyclic conditions. It is well known that timber is characterised by several favourable properties, as lightness (significantly lower than e.g., concrete and steel), high strength-to-weight ratio, proneness to reusability and recyclability (under...

Timber construction is increasingly regarded as a key solution for sustainable building due to its low carbon footprint, renewability, and efficiency in prefabrication. These properties, combined with timber’s lightweight and design and construction in combination with steel connectors, make it particularly attractive in seismic regions, where reducing building mass and ensuring energy...

Rapid earthquake damage and loss assessment is a critical process for evaluating the immediate impacts of seismic events on infrastructure and populations. It involves the quick analysis of structural damage and economic losses. The goal is to provide timely information to emergency responders, government agencies, and decision-makers, enabling efficient resource allocation and disaster...

The destruction caused by recent earthquakes worldwide highlights the urgent need to assess buildings, especially those in medium-high-seismic-prone areas. Over the past few decades, advances in earthquake engineering have led to new methods to evaluate the hazard levels in buildings. Several seismic evaluation methods have been developed across the world. One such method, which is both rapid...

The seismic vulnerability assessment of existing urban areas provides fundamental information about the process of reduction of seismic risk in different phases of planning and emergency management. This contribution presents recent advances in seismic vulnerability assessment in Croatian coastal areas at different scales, starting with a detailed analytical approach at the building scale to...

This paper presents the procedure for remote testing of various categories of bridges, incorporating both static and dynamic assessment methodologies. The investigated structures include different types of bridges categorized by the structural system and materials, as well as different categories of bridges according to their usage. Therefore, the study incorporates a cable-stayed steel...

There are many cases around the world where vertical extensions of existing buildings are favored as alternatives to the erection of new buildings, which would entail demolishing the old structure as well. Such solutions with vertical extensions have certain benefits, but the design characteristics of the base structures and their condition after years of service urge careful consideration of...

On March 22, 2020, the capital of Croatia, Zagreb, was struck by a devastating earthquake that caused damage to many buildings. The most affected were the structures in the city center, constructed as buildings in aggregates, which are characterized by their architectural style and construction methods typical of urban environments from the Austro-Hungarian Monarchy period of the 19th century....

The dynamic behaviour of sand and sand mixtures containing low-plasticity fines at low confining stresses is of crucial importance for geotechnical engineering, especially in regions prone to seismic activity. Such materials can be found in nature or produced in the laboratory. For these mixtures, the accurate assessment and representation of the initial void ratio, defined by the phase...

The Republic of North Macedonia (RNM) is characterized by a moderate to high seismic hazard. Combined with the vulnerability of the existing building stock, the impact of earthquakes continues to be substantial. The implementation of risk mitigation strategies at regional or national levels includes the seismic assessment of a wide range of buildings. Given the significant social and economic...

A large number of cultural heritage buildings, especially in the Mediterranean area, belong to dry masonry stone structures. In order to be able to make decisions about possibly necessary rehabilitation techniques and to preserve them for future generations, it is necessary to have insight into their behaviour due to expected actions, the most destructive of which is an earthquake. As part of...

Abstract
This study presents an integrated approach to seismic assessment and retrofitting of multi-residential masonry buildings constructed between 1945 and 1963 in urban centers across former Yugoslavia, focusing on Ljubljana, Slovenia. These buildings, characterized by unreinforced masonry walls and prefabricated floor slabs, represent a significant portion of the urban housing stock...

The main purpose of this paper is to assess the seismic resistance of a masonry building from the Austro-Hungarian period in Sarajevo. The building is situated in Sarajevo's old Baščaršija, which is well-known for its marketplace of tiny adobe and wooden buildings from the Ottoman era. It is characterized by specific Austro-Hungarian architecture from the rebuilt Latin district next to the...

The majority of existing bridges originate from various periods of design and construction. Due to their age, they have been exposed to environmental influences, often exacerbated by increased traffic loads and different hazards. For bridges located in areas prone to seismic activity, including our region, it is particularly important whether the structure was designed and built according to...

A large part of the housing stock of the Republic of Croatia consists of buildings that were built in the first half of the 20th century, when seismic regulations were poorly developed. Such buildings do not have quality details and have a high seismic risk.
In this work it a pushover analysis of a reinforced concrete historic high rise building in Zagreb was carried out in order to assess...

Recent global events such as earthquakes, the COVID-19 pandemic, wars, floods and similar crises, which have also affected Croatia, have highlighted the urgent need for rapidly deployable emergency shelters, hospitals and both temporary and permanent housing solutions. Simultaneously, cities around the world are grappling with accelerated population growth, creating a huge need for residential...

Extensive construction of buildings with structural system made of reinforced concrete walls had been started in the early 60s of the last century, as a continuation of the rebuild of Europe after the World War II. This was especially true in the Western Balkan region. In some way these buildings replaced multistorey masonry buildings, enabled significantly higher number of floors and a larger...

The second half of the 20th century was marked by the rise of prefabricated concrete systems used as the best solution for fast construction after the vast devastation of the building stock after the WWII. In Yugoslavia, several innovative structural systems were used for mass construction of multi-family housing blocks. Two large groups of prefabricated systems were: 1) large panel and 2)...

After the recent 2020 earthquakes ML5.5 in Zagreb and ML6.2 in Petrinja, a considerable part of the reported damage to churches, museums, cultural and older buildings and houses was observed in topographical areas of Northern Croatia. Topographic amplification of seismic ground motion can be affected by the topographic irregularity, inducing phenomena such as the focusing of seismic waves, the...

Croatia is located in a seismically active area where moderate to strong earthquakes occur regularly. In addition, the building stock is relatively old and not maintained, so the seismic risk is high. This is evidenced by the damage caused by the earthquakes in Zagreb and Petrinja in 2020. Currently, the reconstruction of earthquake-damaged buildings is mainly carried out using standard...

The vulnerability of the built environment to seismic events has been increasingly evident, particularly in the Balkan region, where recent earthquakes have caused significant non-structural damage to both old and new buildings, often leading to restricted use. In North Macedonia, seismic design standards were introduced only after the catastrophic Skopje earthquake in 1963, with the first...

Seismic retrofitting of critical structures, such as schools, military facilities, and essential infrastructure, is crucial in earthquake engineering. These buildings need to meet higher performance standards than typical structures, aiming to withstand design-level seismic events (Life Safety Limit State, LSLS) and ensure functionality immediately after an earthquake. This involves not only...

Seismic strengthening of masonry structures through repointing is recognized as an effective and economical technique for increasing structural stability, especially in regions with high seismic activity. This paper presents results from a research program that includes laboratory tests of the mechanical properties of masonry and its components: bricks, mortar, and polypropylene strips. The...

This study addresses the behaviour of bare plane RC frames and RC frames strengthened by the addition of masonry infill in combination with the connection of infill and frame elements for earthquake action. The main objective was to explore the possibilities of using infill walls in RC frames as a strengthening method, observing the in-plane cyclic responses obtained through experimental tests...

One of the largest districts, known for its replicated building typologies, has been selected for this study, focusing on six-story reinforced concrete frame structures with infill masonry walls typical of 1960s construction. At the time of construction, building codes did not emphasize seismic activity to the extent that modern standards do, and the construction technology differed...

Large scale complex historical buildings, such as palaces or historical city centres, are usually composed of aggregates that were built or connected in different phases. Consequently, under seismic action, there will be an interaction between the buildings that needs to be taken into account when performing their seismic vulnerability assessment. As seen by past seismic events, historical...

Urban historic centers, consisting mostly of vulnerable unreinforced stone and brick masonry structures constructed without seismic design considerations, experience significant earthquake damage. This paper uses a vulnerability index method to obtain and discuss a pre-earthquake vulnerability assessment of a representative part of Skopje's Old Bazaar. This method calculates a score for each...

Historical structures consisting of unreinforced masonry (URM) are highly vulnerable to seismic forces, with out-of-plane failure mechanism being a primary concern. This vulnerability has often resulted in the collapses of the masonry structures during seismic events. Masonry walls tend to rock and overturn in the out-of-plane direction due to the dynamic loading, leading to either one-way or...

SP-BELA (Simplified Pushover-Based Earthquake Loss Assessment) is a methodology that allows to define the vulnerability of a building taxonomy by associating it with a portfolio of capacity curves. The main advantage of this methodology is that it keeps the capacity of the buildings separate from the demand imposed by the shaking at the site. This makes the methodology highly flexible and, in...

This paper presents the process of constructive renovation of the complex of the belfry, monastery, and church of St. Francis on Kaptol in Zagreb. The complex dates to the 13th century and is located in the heart of Zagreb’s historic center. Constructed entirely in masonry, it reflects the architectural principles and construction techniques of its time, with design solutions tailored to the...

The Serbian Association for Earthquake Engineering (SUZI-SAEE) developed a database platform with photos made during the reconnaissance missions after the earthquakes, with the aim to provide a comprehensive framework for documenting and analyzing earthquake-induced structural damage. This paper presents the main aspects of the database platform with the photos of the SAEE team members. The...

xxx

Some considerations, regarding testing methods, aimed at providing information needed to assess earthquake resistance of heritage masonry buildings, are presented. Various testing methods are available, including non-destructive, semi-destructive, and destructive testing, both in-situ and in the laboratory. Because of specific properties of masonry, non-destructive tests on the basis of...

The roof timber constructions are and have been used extensively to support floors and roofs, nowadays as well as traditionally. They consist of plain timber elements and carpentry joints that work together mainly by contact pressure and friction. The structural response of roof frameworks (especially those in historical buildings) is highly dependent on the behaviour of their joints,...

Reinforced concrete frame structures are treated as moment resisting frames, with different design options. The bearing capacity of such frames can be significantly increased by masonry infill walls that act as shear walls.
The greatest supporting effect of the wall on the frame is expected in in-plane (IP) direction. The IP loads are introduced into the wall as compressive forces, whereas...

Past research has demonstrated that foundation rocking, can reduce demands on the superstructure by dissipating a portion of earthquake energy through soil-structure interaction (SSI). Canadian seismic provisions allow two approaches for foundation design: capacity-protected (CP) and non-capacity-protected (NCP). CP foundations are designed to fully develop the resistance of the seismic...

The focus of this research is to determine the impact of structural eccentricity on the seismic behavior of torsionally sensitive structures. To achieve this, two groups of single-story structural models with different levels of irregularity were analyzed. The dimensions of the structures at the base are 6 m x 5 m, with a story height of 3 m. The total external load on each structure is 300...

Near-surface characterization, i.e., determination of the physical-mechanical characteristics of the soil and rock masses that constitute the terrain structure is crucial in avoiding catastrophic consequences during seismic and geotechnical hazards. Geophysical techniques can provide a comprehensive understanding of subsurface conditions, including the presence of weak zones, local anomalies,...

This paper explores the use of drones in assessing the seismic resistance of existing buildings. The use of drones, combined with advanced data processing systems, enables remote assessment of structures. The significant advantage of this approach is particularly evident when evaluating hard-to-reach areas, such as roofs and chimneys, reducing the risk to engineers and accelerating the...

Contemporary living and the need for renewable energy sources demand innovative “green” technologies that offer structural improvement and simultaneously provide more economical and long-term cost-friendly solutions. In geotechnical engineering, shallow thermo-active geo-structures look like one of the most promising concepts. Thermo-active geo-structures may include base slabs, piles,...

The recent earthquakes in Croatia have reminded us that heritage masonry buildings are highly vulnerable to seismic actions. This paper will focus on the out-of-plane failure mechanisms, which result from scarce wall-to-wall and wall-to-floor connections. To prevent these mechanisms, masonry buildings should have adequate structural integrity, i.e. they should behave like a box.
This paper...

Probabilistic seismic hazard assessment (PSHA) is the international standard practice for seismic risk management worldwide and is used as the foundation for evaluating the basis peak ground motion parameters used by structural building codes for earthquake resistant design (e.g., Eurocode 8). While the existing PSHA map for Iceland, the Icelandic National Annex to Eurocode 8, has effectively...

Seismic risk analysis of building stocks in earthquake prone regions build the entry for any kind of mitigation measures especially in case of fast urbanization in developing countries. Iraq – one of such countries – lies in the northern portion of the Arabian plate, bounded in the North-East by the Bitli-Zagros fold and Thrust belt, where the convergent tectonic boundary between the Eurasia...