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The city of Zagreb, the national capital and economic hub of Croatia, is situated in a seismically active region and hosts a significant array of historical buildings, from the medieval to Austro-Hungarian periods. These buildings possess varying but generally high degrees of vulnerability to seismic loading. This was highlighted in the Zagreb earthquake of 22 March 2020, emphasizing the need for seismic retrofitting in order to preserve this architectural heritage. In this paper, the seismic capacity of one such unreinforced masonry building is considered through a number of analysis methods, including response spectrum, pushover, and out-of-plane wall failure analyses. Given the advantages and disadvantages of the individual methods, their applicability and value in a seismic analysis is considered. Ambient vibration measurements before and after the Zagreb 2020 earthquake, used for model calibration, are also presented. Conclusions are drawn from each individual analysis and later compared. In conclusion, no single analysis method considers all relevant failure modes, and a combination of nonlinear static or dynamic analysis and out-of-plane analysis is recommended. Due to the large volume of the material, it is published in two parts, with ground motion record selection, dynamic analysis, and a comparison of the results published in part two. [ABSTRACT FROM AUTHOR]

Assessment of churches based on empirical data at a territorial scale is a suitable tool to have an overview of the seismic behaviour of this peculiar structural typology and to evaluate their current state of vulnerability. Fragility and vulnerability curves are also aimed to perform the analysis of different seismic scenarios. The paper presents a detailed typological analysis of 633 single-nave churches, as a selected subset of the database previously examined by the authors, with the aim of evaluating more in detail the influence of some parameters, such as masonry typology, church dimensions and presence of the bell tower, on the vulnerability of the overall church. Then, specific analyses are carried out to assess the influence played by single mechanisms on the definition of the overall damage index, with the focus of providing qualitative evaluations and explicit vulnerability and fragility curves related to the most recurring and significant collapse mechanisms. This is an original contribution of the paper in the field of the vulnerability assessment of churches, since nowadays little information is available in the literature about the damage levels related to specific mechanisms, while most attention is still focused on global damage. [ABSTRACT FROM AUTHOR]

This paper addresses how residents can safely access shelters from their buildings. Firstly, we investigated Xiaying Village, a typical community with severe buildings damage at the epicentre of the Ms5.0 magnitude earthquake in Tonghai that occurred on August 13, 2018, and found that the injured residents when escaping resulted from the damage to masonry buildings. Secondly, a probabilistic approach combining response spectrum and allowable maximum acceleration is proposed to estimate the damage risk of masonry buildings with inadequate seismic performance in old communities. Thirdly, three models are proposed to assess the risk of the escape path, which include all scenarios of the escape of residents to shelters. Finally, an accessibility analysis of the paths that residents may choose to escape to the shelter is presented. The results of the community escape case study in the Tonghai earthquake show that the probabilistic approach to estimating the escape risk is feasible, and the number of damaged buildings in the escape path dictates the accessibility of residents to the shelter. The proposed method is important for guiding old community residents to escape when a strong earthquake strikes, and it is an effective way to improve community disaster resilience. [ABSTRACT FROM AUTHOR]

The paper investigates the potential of adopting the spectral acceleration Sa(T) as an efficient measure for the estimation of the seismic performance of bare and infilled R/C buildings within the context of Performance-Based Earthquake Engineering. A large number of planar R/C buildings with different masonry infills' distributions are analyzed using nonlinear time-history analyses. The correlation between several damage measures and the Sa(T) for a wide range of periods is investigated. The results point out the conditions under which the Sa(T) can be used as an efficient parameter that describes adequately the damage response of bare and infilled R/C frames. [ABSTRACT FROM AUTHOR]

Despite significant research advances on the seismic response analysis, there is still an urgent need for validation of numerical simulation methods for prediction of earthquake response and damage. In this respect, seismic monitoring networks and proper modelling can further support validation studies, allowing more realistic simulations of what earthquakes can produce. This paper discusses the seismic response of the "Pietro Capuzi" school in Visso, a village located in the Marche region (Italy) that was severely damaged by the 2016–2017 Central Italy earthquake sequence. The school was a two-story masonry structure founded on simple enlargements of its load-bearing walls, partially embedded in the alluvial loose soils of the Nera river. The structure was monitored as a strategic building by the Italian Seismic Observatory of Structures (OSS), which provided acceleration records under both ambient noise and the three mainshocks of the seismic sequence. The evolution of the damage pattern following each one of the three mainshocks was provided by on-site survey integrated by OSS data. Data on the dynamic soil properties was available from the seismic microzonation study of the Visso village and proved useful in the development of a reliable geotechnical model of the subsoil. The equivalent frame (EF) approach was adopted to simulate the nonlinear response of the school building through both fixed-base and compliant-base models, to assess the likely influence of soil–structure interaction on the building performance. The ambient noise records allowed for an accurate calibration of the soil–structure model. The seismic response of the masonry building to the whole sequence of the three mainshocks was then simulated by nonlinear time history analyses by using the horizontal accelerations recorded at the underground floor as input motions. Numerical results are validated against the evidence on structural response in terms of both incremental damage and global shear force–displacement relationships. The comparisons are satisfactory, corroborating the reliability of the compliant-base approach as applied to the EF model and its computational efficiency to simulate the soil–foundation–structure interaction in the case of masonry buildings. [ABSTRACT FROM AUTHOR]

Masonry structures are notoriously vulnerable to horizontal actions caused by earthquakes. Given the high seismicity of the European region, and that the European building stock comprises a lot of masonry buildings, knowledge about their structural response to seismic excitation is particularly important, but at the same time difficult to determine, due to the heterogenous nature of materials and/or constructional techniques in use. An additional issue is represented by the current methods for mechanical properties assessment, that do not provide a reliable framework for accurate structural estimations of existing buildings characterized by different typological properties. Every structure, in other words, should be separately inspected in regard to its mechanical behaviour, based on dedicated approaches able to capture potential critical issues. In this review paper, an insight on the Croatian ARES project is presented (Assessment and Rehabilitation of Existing Structures), including a state-of-the-art of the actual building stock and giving evidence of major difficulties concerning the assessment of existing structures. The most commonly used techniques and tools are compared, with a focus on their basic features and field of application. A brief overview of prevailing structural behaviours and Finite Element numerical modelling issues are also mentioned. As shown, the general tendency is to ensure "sustainable" and energy-efficient building systems. The latter, however, seem in disagreement with basic principles of structural maintenance and renovation. The aim of the ongoing ARES project, in this context, is to improve the current knowledge regarding the assessment and strengthening of structures, with a focus on a more reliable design and maintenance process for existing masonry buildings. [ABSTRACT FROM AUTHOR]

Seismic events that struck Italy in the last years had a dramatic impact on historical and cultural heritage. Damage occurred on existing masonry buildings, in particular on churches, stressed out the need to better understand the seismic behaviour of this type of constructions as well as to define more appropriate mitigation strategies to be applied at large scale. This study deals with a predictive methodology for vulnerability assessment of churches in large territorial areas. Focusing the attention on three naves churches of Abruzzi, the paper proposes modifications and integrations of an existing methodology taken by literature. These modifications are defined through a calibration procedure based on damage observation of 64 three naves churches located at different distances from the epicentre of the 2009 earthquake. The proposed model is employed to predict damage level distribution for different earthquake intensities, allowing fragility curves to be plotted and therefore potential damage scenarios to be represented. [ABSTRACT FROM AUTHOR]

This study highlights the continued need for numerical simulation methods to predict the earthquake response and damage of masonry mosques, despite recent advances in research. The Kamanlı Masonry Mosque in İzmir, Turkey was selected as a case study for this purpose. A probabilistic seismic hazard analysis was conducted using a uniform Poisson process model with 50-year probabilities of 2%, 10%, and 50%. Earthquakes from seismic sources were excluded based on time and distance, and the annual recurrence relationships of the source areas were determined using the least squares method. The non-linear response of a masonry mosque was investigated using the discrete element approach to study the impact of site conditions on its structural performance. Nonlinear dynamic analyses were conducted using records representing seismic events with 475- and 72-year return periods. The results indicated that the mosque is highly vulnerable to earthquakes, as the 475-year records resulted in significant damage and partial collapse. Damage indicators were employed to assess the response to the 72-year records, highlighting the most vulnerable areas that should be prioritized in any restoration efforts. [ABSTRACT FROM AUTHOR]

The paper presents the vulnerability assessment of the Hassan Bey's Mansion, located in the Medieval City of Rhodes in Greece. To this aim, the procedure developed in PERPETUATE project for the seismic assessment at scale of a single monument is adopted: it follows the performance-based concept making use of nonlinear static analyses. The main outcome of the assessment is presented in the paper in terms of maximum seismic intensity measure (the one selected as the most representative for the examined asset) compatible to various performance levels: it is used to address also the rehabilitation decisions. Within this context, the attention of this paper is focused on the use of sensitivity analysis for the identification of the main parameters that affect the structural response. Uncertainties considered in this application are both aleatory and epistemic. The epistemic uncertainties concern the effectiveness of the infilled openings: in fact, this feature strongly characterizes this building that has been subjected to many transformations along its life. Moreover, seven random variables have been considered to account for the aleatory uncertainties: they involve the material properties, the material constitutive law as well as floor rigidity. A total of 60 nonlinear static analyses have been performed for the sensitivity analysis, which represents a powerful tool for setting-up a possible investigation plan and addresses the final assessment. The resulting safety factor, computed in terms of return period, varies from 0.20 to 0.27, highlighting that the structure is not able to satisfy the target performance levels. Possible rehabilitation measures are proposed afterwards, in particular by quantitatively assessing the effect associated to the stiffening of diaphragms (very flexible in the original state). [ABSTRACT FROM AUTHOR]

In the paper, possibilities of correlation of structural damage and damage of attached artistic assets on multi-leaf stone masonry walls by means of destructive and non-destructive testing (NDT) methods are investigated. Results from two testing campaigns carried out at the University of Genoa and University of Ljubljana are briefly presented. In particular, diagonal tests with different levels of pre-compression and shear tests under different boundary conditions were carried out in Genoa and Ljubljana, respectively. During the tests, different damage limit states (DL) of both masonry walls (SE) and attached plasters (AA) were investigated by means of NDT's. Two different types of rubble stone masonry were considered (uncoursed random rubble vs. coursed squared rubble). For AA the results are presented in relative form in dependence from the DL of SE. Obtained results are influenced both by the type of test and tested masonry. Results of NDT revealed strong potential and a need for data fusing of both investigated methods for the evaluation of the state of the degradation behind the plaster. [ABSTRACT FROM AUTHOR]

The paper presents the application of the seismic assessment procedure developed in the PERPETUATE project on a single monument, the Neoclassical School in the Medieval City of Rhodes. The PERPETUATE methodology for the estimation of seismic risk of cultural heritage assets is based on the principles of performance-based assessment ( PBA), using nonlinear static procedures. The outcome of the PBA methodology is the maximum seismic intensity measure compatible to different performance levels. The focus of the paper is on the application of the methodology, considering the effects of both soil-foundation-structure interaction ( SFSI) and masonry foundation flexibility on the building response, before and after rehabilitation design measures. It is found that SFSI and foundation flexibility produce larger displacements and reduce the maximum ground acceleration that the building can sustain by over 50 %. However, despite the detrimental effects of SFSI on the acceleration capacity, SFSI and foundation flexibility may have a favorable effect on the structure safety, as they modify the collapse mechanism. The results of seismic analyses showed that the building, in its current state, does not sustain the demands for the Life Safety and Collapse Prevention performance levels. Stiffening the roof of the structure and providing sufficient anchorage to the structure, along with systematic grouting of the masonry walls, are the principal rehabilitation decisions considered herein. Mitigation measures were evaluated, considering SFSI and the analyses revealed the adequacy of the proposed retrofitting measure, which combines vertical (wall) and horizontal (roof) stiffening. [ABSTRACT FROM AUTHOR]

• Structural damage observed in domes after the 2023 Kahramanmaraş earthquakes, attributed to pulse-like ground motions. • Scarcity of prior research investigating the impact of near-fault pulse-like vertical and horizontal ground motions on the masonry dome. • Understanding the damage behavior of masonry domes under pulse-like ground motions, particularly highlighting the vertical component's significance. • Identification of damage patterns in masonry domes resulting from tensile strains and stresses induced by pulse-like ground motions. • A cost-effective seismic FRCM strengthening technique characterized by minimal intervention, enhanced workability, and reduced cost for masonry domes. • Provision of valuable insights for practitioners and contribution to the refinement of guidelines for masonry domes situated near fault lines. Masonry domes have been used extensively in historic architecture, covering large interior spaces in structures ranging from temples, mausoleums, palaces and fortresses to baths, churches, and mosques. This research is motivated by the post-earthquake observations following the 2023 Kahramanmaraş earthquakes, which revealed significant structural damage to masonry domes caused by near-fault pulse-like horizontal and vertical ground motions. Previous studies in the literature have not investigated the impact of near-fault pulse-like vertical and horizontal ground motions on the seismic performance of masonry domes. This paper aims to explore the impact of the vertical component on the seismic damage behavior of masonry domes subjected to near-fault pulse-like ground motions. Additionally, it seeks to propose a cost-effective seismic strengthening technique characterized by minimal intervention, improved workability, and reduced cost. A 3D finite element model of a masonry dome with a drum was created using the isotropic continuum macro modeling technique with homogenized properties. The Concrete Damage Plasticity (CDP) model was selected as the nonlinear material model. Near-fault pulse-like vertical and horizontal ground motions recorded during the February 6, 2023, Kahramanmaraş earthquake (M7.7) were chosen for the nonlinear analysis. Initially, displacements, tensile strains, and damage patterns of masonry domes subjected to near-fault pulse-like vertical and horizontal ground motions were obtained and thoroughly evaluated for V/H (the peak vertical ground acceleration to the peak horizontal ground acceleration ratio) ratios of 0.0, 0.50, 0.75, 1.0, and 1.25. Subsequently, seismic analyses were conducted on masonry domes strengthened with four different Fabric Reinforced Cementitious Mortar (FRCM) configurations under near-fault pulse-like excitations with a V/H ratio of 1.25 to propose an optimal strengthening technique. [ABSTRACT FROM AUTHOR]

This study presents the most recent development of a nationwide earthquake risk model for non-engineered masonry buildings in Malawi. Due to its location within the East African Rift, Malawi experienced several moderate earthquakes that caused seismic damage and loss. Recently, a new probabilistic seismic hazard model has been developed by considering fault-based seismic sources, in addition to conventional areal sources. The most recent 2018 national census data provide accurate exposure information for Malawian people and their assets at detailed spatial resolutions. To develop seismic fragility functions that are applicable to Malawian housing stocks, building surveys and experimental tests of local construction materials have been conducted. By integrating these new developments of seismic hazard, exposure, and vulnerability modules, a quantitative seismic building collapse risk model for Malawi is developed on a national scale. For the rapid computation of seismic risk curves at individual locations, an efficient statistical approach for approximating the upper tail distribution of a seismic hazard curve is implemented. Using this technique, a seismic risk curve for a single location can be obtained in a few seconds, thereby, this can be easily expanded to the whole country with reasonable computational times. The results from this new quantitative assessment tool for seismic impact will provide a sound basis for risk-based disaster mitigation policies in Malawi. [ABSTRACT FROM AUTHOR]

The response of historic masonry buildings to tectonic ground displacements is studied through analysis of a simple yet representative soil-foundation-masonry wall system. A nonlinear 3D finite element method is developed and employed to reproduce the strong nonlinear response of the rupturing soil, as well as the masonry structure. Following a sensitivity analysis of the effect of the exact location of the structure with respect to the emerging fault, the paper discusses several characteristic mechanisms of soil-structure interaction and evaluates the associated structural distress. The observed failure pattern and the consequent structural damage are shown to depend strongly, varying from minimal to dramatic, on the exact position of the structure relative to the fault. Alleviation of tectonic risk through foundation enhancement/improvement is investigated by considering alternative foundation systems. Results highlight the advantageous performance of rigid embedded and continuous foundations as opposed to more flexible and isolated supports indicating that foundation strengthening may provide important shielding against settlement and structural drift. [ABSTRACT FROM AUTHOR]

In this paper we propose reduction factors accounting for the decrease of stiffness of monumental masonry foundations due to aging, weathering, or other deteriorating effects. The proposed reduced stiffness values can be readily used in finite element structural analysis software in the framework of performance-based assessment, representing linear elastic springs at the foundation level. These springs account for foundation-soil system flexibility and soil-foundation interaction (SFI) at low-frequency vibrations. Accordingly, we propose a procedure to reduce monumental masonry foundation-wall stiffness from the rigid-footing assumption, with respect to the relative stiffness between the foundation and the soil. The proposed procedure is applied to the historical structure Arsenal De Milly in the Medieval City of Rhodes, where period elongation and ductility increase are highlighted, because of SFI and foundation flexibility. [ABSTRACT FROM AUTHOR]

The seismic assessment of rocking masonry structures is a complex task, due to the high sensitivity of the behavior to the characteristics of the input motion. The paper compares the results offered by different models and the reliability of widely used intensity measures. A displacement-based approach based on an incremental limit analysis of rigid blocks is proposed for the performance-based assessment of rocking masonry structures, such as: rocky structures (archeological remains, obelisks, columns, trilithons), arch-piers systems (e.g. triumphal arches, belfries), out-of-plane mechanisms of walls (standing out walls, façades in buildings or churches etc.) or artistic assets prone to overturn (pinnacles, statues etc.). The method is compatible with the format of the PERPETUATE performance-based assessment method for cultural heritage assets [ABSTRACT FROM AUTHOR]

Ancient monumental masonry buildings are complex structures that were not based on an engineered design, underwent many transformations during their life and often present lack of connections among the structural elements. Earthquakes are the main cause of damage for ancient masonry structures and, in order to reduce their vulnerability with compatible and light interventions, it is necessary to have accurate models for the seismic analysis, able to simulate the nonlinear behavior of masonry, and a well defined performance-based assessment procedure, aimed to guarantee the acceptable level of risk for the occupants and for the conservation of the monument itself. The paper outlines the guidelines that were developed within the PERPETUATE European research project. The wide variety of architectural assets is classified and the related proper modeling strategies are identified; moreover, immovable artistic assets are considered in the assessment. A displacement-based approach is adopted, because these structures crack even for low intensity earthquakes and can survive severe ones only if they have a sufficient displacement capacity. Safety and conservation requirements are proposed by considering distinct sets of performance levels, related to use and safety of people, conservation of the building and of the artistic assets that might be present. Some indications on the seismic hazard assessment are provided, considering the distinctive features of some types of ancient structures. Within the fundamental knowledge phase, sensitivity analysis is proposed in order to address and optimize the in-situ investigation and to define proper confidence factors, aimed to consider epistemic and statistical uncertainties. Different modeling approaches and methods of analysis are considered, depending on the characteristics of the structure; both static pushover and incremental dynamic nonlinear analyses are considered. Related verification procedures are defined to evaluate the seismic intensity measure, and the corresponding return period, which is compatible with each performance level that must be fulfilled. [ABSTRACT FROM AUTHOR]

Frequently occurring moderate earthquakes in the Indian subcontinent have extensive impact on the nonengineered shelters of the local people inhabiting them because these shelters generally consist of unreinforced masonry walls. Through a reconnaissance-based damage survey of two such earthquakes in the Eastern Himalayas and that of another in the plains, the present paper identifies the absence of proper connections at masonry junctions as the principal cause of damage. To augment junction strength subjected to reversible lateral loading, the survey proposes reinforcing with L-shaped steel dowels or encasing with polypropylene bands, which incurs a minimal cost increase. The results from shaking table tests show that such measures may lead to a quantifiable increase in the lateral strength of the junctions, which helps in evolving empirical design guidelines at the artisanal level. [ABSTRACT FROM AUTHOR]

The objective of this study was to use rapid visual screening (RVS) methods to identify potential seismic hazards for Oregon’s public facilities, including schools, hospitals, fire stations, police stations, and emergency response centers. There were 1,075 buildings screened in nine western Oregon counties. This study is part of a larger effort under the 2005 Oregon Senate Bill 2 to assess the seismic needs and upgrade public facilities in Oregon. RVS methodology generally followed FEMA 154 Rapid Visual Screening of Buildings for Potential Hazards: A Handbook. This method identifies structural type and building characteristics that may indicate poor performance under the maximum considered earthquake (MCE). Each building is given a final score related to the probability of collapse under the MCE. Screening was conducted by four individuals over three months. Quality assurance (QA) testing on nine buildings examined consistency between screeners. QA results showed final scores varied between screeners depending on building size, structure type, and architectural cladding. FEMA 154 was developed using California buildings. Differences between Oregon and California construction and the use of FEMA 154 in Oregon are discussed in this paper, reviewing the Uniform Building Code (UBC) and Oregon Structural Specialty Code (OSSC) amendments. The study provided two important conclusions. First, the average final score for buildings screened fell below the FEMA 154 cut-off score of 2.0 Second, the OSSC had an exception to the UBC that allowed the construction of unreinforced masonry buildings two stories or less in height. With this context, screening results can help in assigning priorities for further analysis and seismic retrofits. [ABSTRACT FROM AUTHOR]

Historical masonry towers constitute a great part of Italian built heritage: wonderful towers and bell-towers can be observed all over the territory. Such structures exhibit many aspects which are difficult to describe from a numerical point of view. Among the most common: i ) the restraint condition at their base is not exactly clear as they are often embedded in other buildings (such as church bell-towers); ii ) the material behavior is not very clear as the masonry is often made of three layers, each one with different mechanical characteristics. Simplified models can be set up for these structures in order to assess their relative seismic risk, i.e. such models may be applied to a set of nearby towers in order to identify the most prone towers to earthquakes. A deeper insight into their behavior, nevertheless, requires reliable nonlinear numerical models. In the paper, in this respect, some constitutive models already implemented in a finite element software (Code Aster) are employed to perform static nonlinear analyses on a prototype of masonry tower (a cantilever beam), and the obtained results are then compared. The parameters required by each constitutive model have been tuned to obtain comparable values of compressive and tensile strengths, and subsequent comparison is presented. Eventually, a fiber continuous simplified numerical model is also presented; it takes into account several degrees of freedom, chosen as the displacements of the vertical axis of the tower. Nonlinear behavior and damage of the material, along with the efficiency of cross sections, are taken into consideration. The model compares satisfactorily with more complex analyses performed with Code_Aster. The comparison shows both the main advantage and the main limitations of the simplified fiber model. [ABSTRACT FROM AUTHOR]

This paper presents experimental and numerical investigation of a historical masonry building, Omar Toson palace, subjected to static and earthquake loading in order to assess its structural behaviour and seismic vulnerability with respect to its actual state of conservation. The static behaviour and the dynamic properties of the Palace have been evaluated using the finite element modelling technique, taking into consideration all the geometrical and material nonlinearities, in order to investigate the seismic behaviour of the structure by means of nonlinear analysis. A macro-modelling approach has been used based on the concepts of homogenisated material and smeared cracking and crushing constitutive law. The calculations took the values for external loads, earthquake and displacement into consideration. A full 3D non-linear time-history analysis of the entire structure has been done in order to correctly assess the seismic vulnerability of the palace. The numerical analysis has given a valuable picture of possible damage evolution and provides a basic understanding of the structural performance under seismic loads that can support the selection of possible retrofitting measures. [ABSTRACT FROM AUTHOR]

According to seismic activity experts, the 1830–1930 architectural heritage of Algiers faces a serious vulnerability due to earthquake risk in the area of Algiers. Experts point out the acute sensibility of the masonry construction system to earthquakes. However, despite such vulnerability, this heritage is still standing in such a way that defies experts. This paper seeks to attest, through computer modeling, a new light on the impact of buildings architectural proportions upon their behavior during earthquakes. [ABSTRACT FROM AUTHOR]

The main objective of this study was to estimate the damage rate of steel and masonry buildings for different regions of Taiwan from future earthquakes according to the empirical data of 1999 M 7.6 Chi-Chi earthquake, Taiwan. The results are presented in quadratic equation relating building damage rates with modified Mercalli intensity. It is found that two zones are subject to high building damage rates. One zone extends from Hsinchu southward to Taichung, Nantou, Chiayi, and Tainan in western Taiwan, and the other extends from Ilan southward to Hualian and Taitung in eastern Taiwan. These zones are also characterized by low b values and also coincide with high peak ground shaking parameters. We also present the damage rates as function of waiting time for steel and masonry buildings in ten main metropolitans of Taiwan. The results show relatively low expected damage rates in Hengchun, Tainan, and Kaohsiung. But relatively high damage rates are found for most other areas. These results should be of use to government regulators and practicing engineers to enforce appropriate building codes to effectively mitigate potential seismic hazards. [ABSTRACT FROM AUTHOR]

In the framework of PERPETUATE, LOG-IDEAH: 'LOGic trees for Identification of Damage due to Earthquakes for Architectural Heritage' has been developed as a post-earthquake assessment tool for the evaluation of the global seismic performance of architectural assets (AAs). LOG-IDEAH is an expert system which interprets the seismic damage collected on site by relying on the knowledge of engineers and architects in seismic vulnerability assessment. The present expert system has been set up on logic trees, implemented in answer set programming to encode the recognition process that surveyors proceed to investigate the causes of damage and to evaluate the failures occurring on an AA. LOG-IDEAH, available at (), allows sketching AAs, recording the state of damage, uploading GPS referenced images and comparing collapse mechanisms observed on site with collapse mechanisms identified by the system. The seismic damage, which is the minimum data required by LOG-IDEAH, is collected at the level of both structural elements and artistic assets (local level) and interpreted at the level of the AA (global level). The answer set programming applied for the construction of the machine-processable representation, once the input data has been recorded into the web-interface, provides all possible failure modes and related possibilities of occurrence by taking into consideration the reliability level of the collected data. Its capability has been validated by applying LOG-IDEAH to the historic centre of L'Aquila of the 2009 earthquake by pointing out that answer set programming is a valid alternative approach to the existing methods developed to identify the seismic performance of masonry AAs. [ABSTRACT FROM AUTHOR]

Within the framework of PERPETUATE project for the case study in Slovenia, the 150 year old Kolizej Palace in Ljubljana was set. The building was for a long time neglected and severely deteriorated due to ageing and moisture problems. Despite the overall opinion among conservators upon its preservation, it was set to be demolished. Prior it's demolishing in 2011 extensive on-site investigation was carried out, which provided valuable data regarding the influence of deteriorated masonry on the seismic response of the building. Experimental tests proved almost completely saturated moisture conditions in the ground level of the building, while all the stories above were in almost dry condition. The results of tests on masonry revealed that moisture content and state of deterioration affected both strength and stiffness properties of built masonry in large extend. Regardless adopted modelling strategies the vulnerability assessment of the Kolizej Palace has proved that the building in its latest condition was far behind the current code requirements in respect to both static and seismic actions. [ABSTRACT FROM AUTHOR]

Worldwide cultural heritage and especially the heritage buildings in Europe are masonry buildings. Such buildings are generally capable to resist vertical loads but horizontal earthquake actions are often critical. The strengthening upgrade is generally required. One of the most promising methods for the strengthening of masonry walls is application of fibre reinforced polymers (FRP) to the surface of the wall. Three sets of the experimental research were performed recently with new innovative configurations of the fibre reinforcement placement on clay brick masonry. Within the framework of European FP7 research project PERPETUATE two sets of in-situ experiments were performed on 12 walls, belonging to two buildings approximately one hundred years old. Both buildings were made of solid bricks in low strength mortar. Third set of tests was performed in the laboratory on 16 specimens made of contemporary solid bricks in good lime-cement mortar. Tests were performed with different reinforcement configurations. Carbon FRP strips were epoxy-bonded horizontally, diagonally or combined (horizontally and vertically). Glass FRP grids were placed in the modified cement mortar over the entire surface of the wall. Specimens were tested under the constant vertical load and by a displacement controlled horizontal cyclic loading. The carbon fibre reinforced polymer strengthening significantly increased the ultimate displacement capacity in case of the horizontal and combined strengthening. The diagonal strengthening was not so effective because the failure of the diagonally strengthened specimens was governed by the peeling of strips from the masonry. The GFRP grid configuration greatly increased the load bearing capacity but not also the ultimate displacement. The shear strength of the strengthened and un-strengthened specimens was compared to the calculated values of the seismic shear load bearing capacity. For that the Triantafillou (J Compos Constr 2(2):96-104, ), Triantafillou and Antonopoulos (J Compos Constr ASCE 4(4):198-205, ), Marcari et al. () and Wang et al. (Asian J Civil Eng Build Hous 7(6): 563-580, ) calculation models and the design guides ACI 440.7R-10 () and CNR-DT 200/2004 were used. [ABSTRACT FROM AUTHOR]

The effect of uncertainties regarding modelling choices and knowledge of specific structural configurations on the seismic vulnerability evaluation of masonry buildings in Slovenia were studied using two case studies: a set of damaged buildings from the rural area of NW Slovenia hit by earthquakes in 1998 and 2004 and the urban buildings from the historic city centre of Ljubljana. Two modelling strategies were applied-failure mechanisms analysis by means of macro element methodology (MEM) and non-linear response analysis by means of structural element modelling. The accuracy in predicting failure modes by MEM ranged between 50 and 80 % of the stock of building in rural area. The most critical failure mechanisms were due to out-of-plane loading. Given the uncertainties associated with the data relative to the urban architecture stock, the MEM analysis was carried out considering different hypotheses, leading to a range of 30-70 % damaged buildings, for 475 years return period, with diverse failure mechanisms and ultimate capacity depending on specific structural assumptions. For one building of rural architecture already damaged during previous earthquake in 2004, where due to the extensive in-situ campaign the influence of uncertainties were minimised, direct comparison of the effectiveness of both methods were investigated. MEM assessment yields more conservative results in respect to non-linear approach and thus may be an efficient tool for the design of strengthening measures for heritage buildings to prevent damage in lower intensity events with higher probability of occurrence. [ABSTRACT FROM AUTHOR]

To address concerns regarding the seismic vulnerability of New Zealand unreinforced masonry (URM) buildings, a research program was undertaken to investigate the effectiveness of fiber-reinforced polymer (FRP) systems as a seismic retrofit intervention for in-plane loaded URM walls that are prone to fail in a shear mode during earthquakes. Seventeen URM wallettes were retrofitted with either externally bonded (EB) glass FRP fabrics, EB pultruded carbon FRP (CFRP) plates, or near-surface mounted pultruded CFRP rectangular bars. The wallettes were tested by the application of a diagonal compressive force, and data were recorded for applied force and corresponding wall drift. Results were compared with five nominally identical unretrofitted wallettes. It was determined that the FRP systems substantially increased the shear strength of the wallettes. Significant increases in the pseudoductility and the toughness were also obtained, which are all considered to be important goals of any seismic retrofit intervention. [ABSTRACT FROM AUTHOR]

The article discusses the in situ experimental test campaign conducted on traditional masonry houses concerning the July 9, 1998 earthquake in Faial Island, Azores. It states that self-equilibrated scheme becomes the basis for the in situ test setup. It mentions that the experiment tests five specimens and aims to characterize the stone masonry walls out-of-plane behavior and recommended solutions for strengthening post-earthquake intervention. An in-plane test was conducted on an unreinforced masonry (URM) panel to examine the set-up's efficiency for other applications concerning the stone masonry walls. It also says that the conducted experiment contributes to the architectural heritage preservation and the reduction of seismic vulnerability.