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Monitoring of non-structural elements is not usually implemented, despite the seismic vulnerability of these components and the significant cost associated with their replacement in case of damage. By exploiting the limited cost of commercial sensors, accelerometers were installed in an existing building to compare accelerations applied to non-structural elements in case of an earthquake with critical acceleration thresholds. The exceedance of these thresholds would indicate a possible danger for the occupants and the need for a more detailed inspection of the element, guiding prioritisation strategies in the aftermath of the earthquake. Furthermore, the real-time probabilistic assessment of potential damage to non-structural elements can serve to identify escape routes and facilitate rescue operations. Critical acceleration thresholds were defined from probabilistic considerations on the expected seismic performance of each typology of non-structural element, described by appropriately selected fragility curves. The feasibility of the proposed procedure was tested by comparing the identified acceleration thresholds with the design values of floor acceleration provided by the Italian Building Code. As a further application, critical acceleration values of the different non-structural elements were compared with a set of real floor acceleration values recorded at the top level of reinforced concrete buildings, highlighting critical non-structural element typologies.

The assessment of seismic risk for critical and strategic structures like schools and hospitals remains crucial, even in regions with low seismic activity. Presently, operational school buildings in Sri Lanka are primarily designed to handle gravitational loads without considering capacity-based design principles. Consequently, these structures may lack the necessary lateral resistance to mitigate potential damage or collapse during future earthquakes in Sri Lanka. Hence, conducting seismic risk assessments for such school buildings is imperative to ensure the safety of their occupants. In this research paper, we utilize a recently developed probabilistic seismic hazard map for Sri Lanka to evaluate seismic risk. We employ two nonlinear 3-D finite element models of school buildings created in OpenSees. Incremental Dynamic Analysis is conducted using a well-established set of ground motions, continuing until the structure approaches the point of collapse, to determine the probability of collapse prevention. Subsequently, we develop fragility functions for two limit states, immediate occupancy, and collapse prevention. These fragility curves are then used to compute the probability of exceeding these limit states, aiding in the assessment of the structural safety of the school buildings. A key outcome of this analysis reveals a general trend of increased damage probabilities as the number of stories in the buildings increases despite the distinct structural characteristics of each building. It is also important to note that the disparities between the immediate occupancy and more severe damage cases, such as collapse prevention, are notably pronounced in both two- and three-story school buildings.

During the Puebla earthquake on September 19, 2017, about 200 steel buildings were subjected to a severe shake in the State of Mexico, Puebla, Morelos, and Mexico City. Although null or minor structural damage was reported, design and assembly opportunity areas in some beam–column moment joints were identified during the post-seismic inspections. With this in mind, six beam–column connections, widely employed in steel frame structures by the local practice, were experimentally tested through natural-scale. A damage concentration with not enough ductile response for high-ductility steel structures was reported. Welding parameters and fabrications details are emphasized to improve the response for new structures, and a rehabilitation suggestion for existing structures is discussed. This research is part of a study that aims to establish the vulnerability of steel structures in Mexico. [ABSTRACT FROM AUTHOR]

Application of green adaptive reuse (GAR) is considered to be difficult and lacks the attention in the field of research. The potential of implementing GAR has become uncertain since the way of implementing specific practices is still unknown when the context is different. In Sri Lanka, building professionals are reluctant to use GAR approach due to various obstacles. Specially, due to the scarcity of land, high energy consumption and costs, most of the existing abandoned buildings in Sri Lanka are demolished despite the significant benefits of GAR of buildings. Thus, this research is aimed to develop a framework that could facilitate the implemention of GAR for existing buildings in Sri Lanka. A qualitative research approach was followed for this research with semi-structured interviews. The findings were analyzed using the content analysis method. Significant factors for the implementation of GAR approach were identified mainly under seven criteria including physical, economical, functional, technological, social, legal and political. Further, barriers and strategies for the implementation of GAR for existing buildings in Sri Lanka were revealed. Based on the findings, a framework was developed as a guidance for the implementation of GAR for existing buildings in Sri Lanka which was the key outcome of this study. [ABSTRACT FROM AUTHOR]

Among the buildings with strategic role for civil protection purposes part of them were built before the introduction of modern seismic codes. Aiming to guarantee their operability in case of seismic events, they have to be assessed and, hopefully, seismically upgraded. This aspect arises the necessity of reliable low computational demanding numerical models and probabilistic strategies that can be easily adopted in case of the assessment of conspicuous building stock. Part of the authors proposed and validated, in previous works, a low-demanding seismic model calibrated on ambient vibrations (SMAV) that is engaged in this paper for calculating fragility curves. On the base of dynamic and geometric properties, the SMAV model simulates the dynamic response of buildings. The herein proposed procedure adopts the SMAV model and takes into account the direction of seismic input in a probabilistic manner. The use of the ASI scale as an Intensity Measure parameter is discussed and the results are compared to those obtained with others IM scales. Although SMAV implements an equivalent linear procedure the results are compared with those obtained by more sophisticated FEM models and nonlinear dynamic analyses with a satisfactory agreement. Finally, two real case studies are presented. The fragility curves for both the case studies are calculated and discussed. The results encourage the authors to the use of fragility curves based on SMAV model. Additionally, the fragility curves can be easily implemented in seismic risk assessment procedures at urban or territorial scale and, consequently, the proposed procedure may represent a key aspect in the reduction of seismic risk and rationalization of investments for the seismic upgrading of strategic buildings. [ABSTRACT FROM AUTHOR]

This study takes an old oceanarium in Jiangsu Province, China, as a case study and monitors the energy consumption values related to electricity, water and gas consumption for the whole year before the renovation of the oceanarium. Based on the energy consumption monitoring data, an in-depth analysis of the energy consumption defects of the oceanarium before the renovation is conducted using energy audit technology. We combine the characteristics of the oceanarium itself according to: (1) the results of the building energy audit; (2) the results of the envelope calculation; and (3) the latest energy-saving retrofit technology. We developed a more scientific building energy-saving retrofit programme. Using this method, we can accurately monitor the energy consumption problems in old oceanarium buildings and find building energy consumption defects. In this study, we monitor the real-time energy consumption of nine old government office buildings in Jiangsu Province, China using energy monitoring technology. We analyse and study the monitoring results and finally target the scientific energy-saving retrofits. This method can be used to carry out targeted energy-saving building renovation in the future and put forward new methods and ideas for studying the energy consumption of existing public buildings., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Although Architects focus on applying various requirements in designing different types of buildings & projects to achieve human, functional, economics…etc. needs, it is obvious that human safety needs concerning fire protection codes are mostly neglected, which, over time, threatens the safety of buildings. Therefore, many buildings do not fulfill life safety codes, either due to poor implementation or because of legislation causing an immediate danger to society, which requires checking all existing buildings, especially the ones implemented before issuing & applying the life safety code in Egypt.Hence, this paper aims to set a reference matrix to redesign existing buildings, focusing on “Assembly Occupancy Buildings”, being one of the most buildings that deal with a diverse number of users and for their common existence in many places.Furthermore, the paper aims to apply the matrix on a selected building and redesigning it according to the life safety code requirements.The paper also presents two buildings in the Faculty of Engineering at Fayoum university and another building at the Administrative Capital University. It is also applies the matrix on the Multi-purpose hall of one of the mosques in New Cairo (5th. Settlement).The paper concludes a matrix that includes a set of design decisions to adjust or redesign existing buildings to meet the life safety code requirements.

This paper introduces actual considerations for the progressive disuse of residential space in the Alpine territory, considering possible actions. Nowadays, the building complexes built around the 1960s and 1970s (a symbol of mass tourism) are suffering and searching for a new identity. The generation of owners who bought them has aged and the propensities of the new generations for holiday in those places has changed, which means fewer opportunities for leisure, particularly in the winter. Due to the great attention (and seeming opportunities) of current incentive policies toward improving the energy use of the existing stock, the authors investigate the private conveniences of transformations through the refurbishment of these buildings. Starting from a study of the territory and the dynamics of the local population, this research analyzes a possible set of energy works, based on a new (2020) incentive measure, the 110% Superbonus, which consists of a series of facilitation mechanisms, deductions, and reimbursements for building interventions. A large part of the insight is focused on a technical and economic feasibility study of the possible actions, following a process based on the evolution of the legislation. This work is based on a specific case study, located in a small municipality in the Piedmont mountain area, consisting of three apartment blocks of mostly second homes. The methodology adopted lends itself on the one hand, as a guide for preliminary economic energy assessments and, on the other hand, as a policy evaluation tool from the public and private perspectives.

Concrete cores extracted from the same structural element may show variations in strength resulting from a lack of homogeneity and variations in the grade of compactness. This paper, while accounting for such variability, introduces a new formulation to assess both in situ and the potential characteristic strength of concrete. The first part addresses the Concrete Society report 11 on formulations and the formulation introduced by the author that considers new coefficients that take into account the addition of water to the cement mixer and the influence of excess voidage. The second part describes a case study in that the procedures were applied to an experimental campaign carried out on two series of cores. The visual means method proposed by report 11 is applied for excess voidage assessment to the first series of cores, while a computed axial tomography (CAT) scan allowing a direct estimate of the percentage of voids in different sections is applied to the cores of the second series. Results show noticeable variations in the percentage of voids within the same drilling. Moreover, the proposed formulation can estimate the actual value of both the in situ and potential characteristic strengths of concrete with a reasonable degree of approximation. Finally, a computed axial tomography (CAT) scan leads to extremely precise results, making it possible to evaluate the percentage of voids in different sections of the same core.

Most existing masonry buildings were built without following code regulations for seismic criteria. Hence, their performance compared to the demands of the current codes, for both seismic and static actions, could be very low. In engineering practice, strengthening interventions can be pursued at different levels, based on qualitative assessments of masonry structures. Firstly, the structures are evaluated through in situ inspections. Then, based on the structural system of the building a strengthening design is proposed. The design can be targeted at guaranteeing a box behavior of structures acting through macro-elements, or at strengthening the in-plane capacity of piers and spandrels. However, lower cognitive levels may drive inaccurate impressions about the capacity of structures, leading to unreliable strengthening solutions. While in some cases the confidence factor could underestimate the effects of the reinforcements, in other cases lower knowledge levels could lead to incorrect reinforcements that do not provide helpful solutions. In this paper, the issues concerning the strengthening design of masonry structures are presented and discussed with regard to an existing building. The construction is a 20th century masonry building used as a nursing home for elderly persons. The study follows a knowledge-based procedure where, after achievement of the highest knowledge level and the proposal of compatible and effective strengthening interventions, the analysis of the potential effects of achieving lower knowledge levels is discussed both in terms of vulnerability computations and in terms of strengthening effectiveness. Regarding vulnerability assessment, a lower knowledge level leads to non-conservative results, with an increase in the estimated capacity of around 80%. Critical evaluation of the different configurations for the case study makes it clear that for the considered masonry building the mortar investigation represented the most important parameter to be investigated. The proposal of strengthening interventions before assessment of this parameter may lead to ineffective improvements resulting in index values lower than 0.60. The study represents the opportunity to assess comparisons in the setting of different investigation strategies and their effect on the definition of the strengthening solutions.

Background. Renovation of existing buildings has become a crucial tool to keep the built environment functional, by which unnecessary waste of resources can be reduced. Although many assessment methods and indicators are set, with the booming "renovation wave", a question that counters us is how influential and intact these are as a measuring tool. Several debates have emerged in the literature on the integration of different indicators and approaches to have a better way of accessing the buildings. Purpose. The aim of the study was, first, to have a set of integrated indicators for the renovation of residential buildings and, second, to develop an assessment methodology aimed at a comprehensive evaluation of the renovation process throughout its lifecycle stages. A requirement specification and an outline of the tool were developed based on the literature review and the survey. Design. The study has applied a qualitative multi-method research approach, including an online survey with experts, and case studies. The survey was part of renovation needs, barriers and evaluation methods and indicators comprising four sections addressed to experts about building renovation. The aim was, besides collecting general knowledge about the renovation in practice, to identify key indicators and areas where development or modification could have effect during the renovation. The developed methodology was applied in a case scenario of a multi-apartment building in Lithuania. Conclusions. This paper included the development of a combined methodology which applies to the renovation of the existing multi-apartment buildings with a checklist of indicators corresponding to environment, economic, and social aspects. [ABSTRACT FROM AUTHOR]

Climate change is causing more frequent extreme weather events. The consequences of increasing global temperature on the operating cost of existing buildings, and the associated health, safety, and economic risks were investigated. Eight cities in Ontario, Canada, across climate zones 5 to 8, were selected for this study. Statistical models were employed to forecast daily temperatures for 50 years. The impact of climate change on buildings' heating and cooling demands for energy was measured as changes in heating degree days (HDD) and cooling degree days (CDD) compared to current design requirements. The results predict an increase in the demand for cooling and a decrease in that for heating within the next 50 years. A drop in the total HDD and CDD is shown which reflects a more comfortable outdoor thermal condition. Risk to human health attributable to the increase in global temperature is negligible. [ABSTRACT FROM AUTHOR]

The paper presents a methodology of extraction, integration and elaboration of data from different sources using the geographic information system (GIS), to realize a georeferenced building database (GBD) useful for the seismic vulnerability assessment of existing buildings on a large scale. Three levels of GIS entities have been defined and equipped with the related information: census section (CS), urban block (UB), and individual building (IB), depending on the level of detail of dataset. Additional information about the typological and structural features has been extracted by CARTIS catalogue, to refine the data associated with each building. The data have been validated using detailed information gathered on a proper sample of buildings, which have been filed and analyzed one-by-one. The alphanumeric format of data allows for the automatic implementation of different methods available in the literature, which provide a qualitative seismic vulnerability index at different scales (whole urban district, an urban block, and a single building). Finally, the 3D representation of data and results have been elaborated, providing a tool easily searchable and constantly implementable. An application has been developed for a case study in Puglia, Italy: Bisceglie, for which 3726 IB have been assessed. The work addresses the issue of the lack of information typical of large-scale applications, exploiting all the available data sources to achieve nearly complete knowledge of existing building stock finalized to a rapid but extensive evaluation of the seismic vulnerability on an urban scale with very low computational efforts and the use of limited resources in terms of time and cost. [ABSTRACT FROM AUTHOR]

Energy retrofitting for buildings has gained great attention in recent years due to the significant benefits of reducing environmental impacts and costs. Generally, retrofit planning involves considering criteria such as energy savings, emissions savings, and cost savings. However, the rapid transition of climate and extreme climate forces integrate climate adaptation into retrofit practices. This study examines strategies and modifications necessary to transform the current climate mitigation-based retrofit processes into frameworks that simultaneously improve climate mitigation and adaptation. A comprehensive literature review is conducted on building energy retrofit studies based on climate adaptation. It was found that future climate events are anticipated to be more related to overheating than under-cooling in many regions. Passive retrofit strategies can reduce overheating risks substantially, while the dependency on active cooling is unavoidable in warm climatic regions in future climates. Retrofit strategies designed based on traditional approaches may not be effective and may even worsen the risks of overheating in the future climate due to drastic climate change. Climate resiliency criteria must be adapted to the building retrofit field. Climate modelling and energy simulation have a substantial role in designing retrofits, and yet significant research and development is required to penetrate the current retrofit practices. The synthesis of the findings guides the systematic and careful designing and implementation of building energy retrofits. These findings offer valuable insights to policymakers, urban planners, and researchers seeking to improve buildings' energy performance and resiliency and act as a guideline to implement climate change adaptation strategies. • Reviewed climate adaptation-based retrofit designing and planning studies. • Revealed a significant gap in existing retrofit frameworks that consider both climate mitigation and adaptation. • Highlighted careful design and implementation of retrofits is necessary to overcome future climate risks. • Presented a comprehensive guideline to integrate climate adaptation aspects into current retrofit practices. • Suggested future research directions, including the development of climate resilience benchmarks. [ABSTRACT FROM AUTHOR]

The need to improve the performance of Nigeria’s office buildings is due to, energy challenges, increasing population, changing user needs, and climate change. With the expansion of several Nigerian cities, existing buildings constitute a significant portion of the building stock, and improving their environmental performance could be more cost-effective than reconstruction. The use of simulation packages to assess alternative retrofitting enhancement scenarios is a straightforward approach. However, in Nigeria it is often challenging to get appropriate information to facilitate this type of evaluation; many buildings were not built to their original specifications, and when available, the records are often in a poor state due to deterioration. Studies that aimed at enhancing a building’s performance hardly stated the acquisition of the required building information. This paper investigates current practices and future possibilities of improvement measures and data capturing of existing buildings using a questionnaire survey of 133 building professionals in Benin City. The inter-relationship between energy efficiency, the environment, and building design with a high potential for meaningful retrofit to mitigate energy inefficiencies is known but not fully utilized. The collected thought on current practices signifies the need for developing a more economical and reliable methodology for data capturing and evaluation.

Seismic performance of existing buildings constructed before modern seismic design codes is one of the important problems of earthquake prone countries. Increasing life and economic losses after strong earthquakes shows the necessity of seismic performance assessment studies and methods. Therefore, in this study assessment methods recommended by different seismic codes were investigated and probabilistically assessed by comparing the fragility curves of existing low- to mid-rise RC structures. Building performances were determined according to TEC-2007, TBEC-2018, EC8/3 and ASCE 41-17. Eight different occupied buildings, classified according to construction dates (old and new) and story numbers (3 to 6), were selected and investigated by using these codes. At first, building capacity curves and damage limits, defined by the different code methods, were determined via pushover analyses. Structures were then subjected to more than 300 real strong ground motion (GM) records employing nonlinear dynamic analysis and fragility curves were obtained. Static analysis results showed that strength, stiffness and deformation capacity of new buildings are significantly higher than old ones according to all seismic codes considered and it is observed that TBEC-2018 gives the most conservative capacity estimations with respect to others. Comparison of fragility curves indicated that damage probabilities of TBEC-2018 and EC8/3 are higher than other seismic codes and this situation is valid for all story number and building age classes. In most cases TBEC-2018 and TEC-2007 results represent the upper and lower bounds of damage probabilities. It was also found that building age is the most effective parameter that affect the fragilities of existing buildings. Distribution of fragility curves imply that different code methods can give significantly different damage estimations under identical seismic demand levels. [ABSTRACT FROM AUTHOR]

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The aim of this research is to develop a framework for the implementation of Green BIM technology for existing buildings in Sri Lankan context. A multiple case study was conducted under a qualitative research approach. Two existing buildings were selected for the cases. Autodesk Revit was used to design the BIM models of the cases. As Green BIM techniques solar analysis and energy analysis were conducted using Green Building Studio simulation software. Solar simulation results included cumulative insolation as 463,825 and 480,538 kwh, PV energy production as 231,659 and 111,024 kwh/year, energy savings as $34,749 and $16,654 and pay pack periods as 18.5 and 15 years for case 01 and 02, respectively. Further, research revealed the challenges during the application of Green BIM for existing buildings when building data are not adequately available. Moreover, this study proposed the solutions that are taken during the study to overcome the challenges. This study justifies the potential of Green BIM implementation for existing buildings through an in-depth analysis of challenges and possible solutions with a framework that can be used. This encourages building owners and facility managers towards using Green BIM for existing buildings. [ABSTRACT FROM AUTHOR]

A combination of systematic and bibliometric literature review is applied. For bibliometric analysis a citation network analysis, keyword cluster analysis, burst detection analysis and the total citation score are evaluated. So far, literature mainly deals with creation of digital building models. However, in the operational phase of a building, updating digital building models is essential in order to use the digital building models for applications like maintenance, facility management and conversion planning. In this paper approaches and methods to update digital building data are examined systematically to reflect the current state of scientific knowledge. This will identify and compare update approaches for digital building models. Nine interrelated research areas can be identified that deal with updating digital building information. Based on the body of knowledge on the topic "Updating of digital building models", research gaps and poorly represented research areas are identified. One gap in research is the use of photogrammetry to update individual buildings during their operational phase. In addition to strong research areas such as geoscience, which has produced update approaches over the years, areas like factory planning have been identified which hardly consider approaches to updating as-built data. Only the most important and largest research areas involved have been considered. A more detailed examination would be possible, but would go beyond the scope of this paper. This paper is the first to analyse updating approaches in a detailed, systematic, and bibliographic manner. The holistic view of the topic of updating approaches of digital building models helps to get an overview of existing approaches. Especially because in building operation up-to-date digital plan documents of the building are increasingly needed, this overview is necessary. [ABSTRACT FROM AUTHOR]

Nonlinear macro-models of concrete components are routinely used for performance-based seismic assessment of existing "non-ductile" buildings. Accurate test-calibrated models improve cost and time effectiveness of rehabilitation. ASCE 41-17, the primary standard in the United States for seismic assessment and rehabilitation, offers nonlinear modeling parameters for concrete frame beams and columns that were recently updated to reflect median estimates (50% probability of exceedance). However, the ASCE 41-17 beam-column joint nonlinear modeling provisions are still based on lower-bound estimates shown by many researchers to be highly conservative. Moreover, existing literature backbone models are not suitable for shear-critical "non-conforming" unreinforced joints as they are mostly deterministic, non-sensitive to failure mode, designed for reinforced joints, or calibrated based on small unreinforced joint datasets. This paper proposes new probabilistic nonlinear modeling parameters for shear-critical unconfined (unreinforced) beam-column joints based on a database of cyclic tests to update the current ASCE 41-17 modeling parameters. Three alternatives for deformation modeling parameters are proposed, along with two alternative expressions for residual shear capacity ratio. The proposed models offer the analyst to select the desired probability of exceedance to enable consistent modeling criteria with beams and columns in concrete frames to avoid nonlinear analysis bias that is currently rendering joints unrealistically as the weakest link in non-ductile frames, leading to unnecessary costly retrofits. All the proposed models exhibited very good correlation with the test database and verification dataset. The proposed models offer immediate input to reduce the conservatism of the current seismic assessment standards for unconfined beam-column joints, which resulted from test scarcity at the time of their development. [ABSTRACT FROM AUTHOR]

Post-earthquake observations have outlined the poor seismic performance of substandard reinforced concrete (RC) beam-column joints in existing buildings. They often exhibit significant cracking even under moderate intensity earthquakes, compromising the seismic performance of the entire building. This makes the quantification of their residual capacity and the definition of reliable repairability thresholds critical. Different approaches are available in the literature to establish the repairability of RC joints. However, a simple crack width-based criterion is required for practitioners during in-situ inspections. This study deals with the definition of crack width-based fragility curves relying on numerical analyses. Those are carried out by using the validated finite element (FE) models, being capable of reproducing the initiation and development of cracks in RC joints. To this end, the uncertainties in material properties, influencing the seismic performance of structural components, are accounted for different joints. In particular, experimentally validated FE models are evolved to stochastic level by generating random variables of material properties with the stratified sampling scheme. Fragility curves representing a certain level of probability of exceeding the defined crack width at the joint back, joint core, and beam-to-joint interface are developed. An application of the proposed methodology for in-situ inspections is also presented, and the results of in-situ measurements of residual crack width from real buildings damaged by recent earthquakes are used for the validation. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper aims to extract the dynamic properties of existing structures without utilizing the analytical models. The ambient vibration testing could be used on any type of frame such as concrete, steel and masonry to investigate the structural vulnerability. The method could be the first stage and necessarily for the retrofit process. To achieve this aim, the ambient vibration testing can also be employed. The experimental data obtained from the method can be used to monitor the health, evaluating, and damage detection structures at present. The achieved data can be compared in future with the recorded signals at different times. So, the ambient vibration test was carried out on the building of Imam Hossein Hospital at Mashhad. Then, its dynamic characteristics of the acceleration records are obtained by using Data Acquisition System with three accelerometers in two perpendicular coordinates. The method is more accurate and practical compare with analytical models of the existing buildings. The ambient vibration test prevents of several points such as destructive testing or may irreparable damage to the building as well as high cost. Even, the ambient vibration test maybe required for every couple of decayed, when noticed of any changes in the condition of buildings after construction. These type of changes could be quality of concrete or welding or some changes in the location of walls that can be affected the dynamic specifications of the building. The method provides real lateral load pattern and actual modes that can evaluate existing condition of the building compare with the time of construction.

The paper describes a novel Adriseismic method for expeditious assessment of seismic risk associated with unreinforced masonry buildings. The methodology was developed for the Adriseismic project of the Interreg ADRION programme, with the aim to develop and share tools for increasing cooperation and reducing seismic risk for six participating countries within the region surrounding the Adriatic and the Ionian Seas. The method is applicable to unreinforced masonry buildings characterised by three main seismic failure mechanisms, namely masonry disintegration, out-of-plane failure, and in-plane damage/failure. Depending on the input parameters for a specific structure, the assessment yields a qualitative output that consists of the masonry quality index, the index of structural response, the level of seismic risk, and the most probable collapse mechanism. Both input and output of the method are applied in the spreadsheet form. The method has so far been applied in urban areas of participating countries in the project, including Mirandola, Italy; Kaštela, Croatia; Belgrade, Serbia. In parallel, the methodology has been validated by performing a detailed seismic assessment of more than 25 buildings, and the results have been compared with the results of the proposed expeditious method. The results show a good correlation between the two methods, for example, the structural response index obtained from the expeditious method and the capacity/demand ratio obtained from the conventional assessment method.

This work aims to provide an effective structural solution, minimizing the discomfort during the works’ execution, for how to retrofit the Day-Hospital building of the National Cancer Institute “G. Pascale Foundation” in Naples. The structural vulnerability has been preliminarily evaluated for this scope, using linear static and dynamic analyses according to code provisions. The performance index in terms of peak ground acceleration (PGA), both for the life safety (SLV) limit state and the operational (SLO) limit state, has been evaluated. A seismic assessment has been performed by finite element (FE) analyses using the SAP2000 computer program, post-processor VIS15 and plugin SPF. Two main solutions have been proposed to improve the structural performance of the existing building. The first one is based on increasing the thickness of the existing reinforced concrete (RC) cores. The second solution is characterized by strengthening the RC cores using steel plates, steel strips and angles. A comparison of the proposed interventions is provided herein from the technological and financial standpoints.

Seismic isolation devices, as known, are particularly efficient tools for the protection of newly designed or existing buildings and infrastructures and for the mitigation of maximum effects due to earthquakes. The highest is the vulnerability of a given existing construction, and the higher is the benefit in structural terms due to a possible retrofit intervention based on base isolation. This is especially the case of reinforced concrete (RC) building frames built in the 1960s in the Italian context and originally designed with a code of the first generation (“Regio Decreto Legge 25 Marzo 1935, n. 640”) in a city characterized by a long history of severe earthquakes (as the Reggio Calabria and Messina earthquake in 1908), and thus recognized as highly seismic regions. In this paper, a case-study application is proposed for the Frangipane school constructed in Reggio Calabria (Italy) and recently subjected to a major renovation intervention for its retrofit against the high seismic hazard.

The existing building stock is largely made up of reinforced concrete (RC) buildings, constructed between the post-World War II period and 1981, and mostly consists of buildings constructed very quickly to meet the great housing demand of this period, and buildings that do not adhere to anti-seismic and energy regulations. Today, after more than fifty years, these buildings have reached the end of their useful life cycle and their maintenance is not sustainable, presenting a series of structural, energy and architectural problems and criticalities. The myriad of possible retrofit interventions currently available for these RC structures drastically reduces when the main requirement for interventions is to avoid operational interruptions to buildings. In this case, an additive structure, operating exclusively from the outside as an exoskeleton, is typically used for achieving appropriate retrofit. In this paper, two solutions are proposed and addressed for the retrofit of an existing RC building in Italy, one through the application of a steel exoskeleton and the other through the application of an RC exoskeleton system. A set of push-over (PO) analyses is carried out to define the performance point of both the original and combined systems. The comparative results of these solutions are then discussed.

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article addresses seismic vulnerability assessment at an urban scale using mechanical methods, more specifically potential improvements by involving typological curves instead of standard capacity curves and by using accurate displacement demand determination for reliable building damage prediction. The impact in terms of damage grades is computed for two typical Swiss cities. In Europe, seismic-vulnerability assessment is usually performed using the Risk-UE methodology, which involves an empirical approach (LM1 method) and a mechanical approach (LM2 method). The LM2 method contains standard capacity curves of conventional building types for computation of the corresponding damage grades. These capacity curves have been developed for southern Europe and are not optimal for describing features of other building stocks. New specific refined capacity curves are developed for northern Europe. Eurocode 8 prescribes the computation of displacement-demand for seismic assessment of existing building through a process based on the N2 method. However, the inaccuracy of the N2 method in certain conditions has already been studied. Therefore, modifications of N2 method have been proposed to improve the reliability of displacement-demand determination. In this study, the impact of typological capacity curves and the modified N2 method are investigated independently. Results show that both refinements contribute to improve the damage-grade distribution assessment. [ABSTRACT FROM AUTHOR]

Among the buildings with strategic role for civil protection purposes part of them were built before the introduction of modern seismic codes. Aiming to guarantee their operability in case of seismic events, they have to be assessed and, hopefully, seismically upgraded. This aspect arises the necessity of reliable low computational demanding numerical models and probabilistic strategies that can be easily adopted in case of the assessment of conspicuous building stock. Part of the authors proposed and validated, in previous works, a low-demanding seismic model calibrated on ambient vibrations (SMAV) that is engaged in this paper for calculating fragility curves. On the base of dynamic and geometric properties, the SMAV model simulates the dynamic response of buildings. The herein proposed procedure adopts the SMAV model and takes into account the direction of seismic input in a probabilistic manner. The use of the ASI scale as an Intensity Measure parameter is discussed and the results are compared to those obtained with others IM scales. Although SMAV implements an equivalent linear procedure the results are compared with those obtained by more sophisticated FEM models and nonlinear dynamic analyses with a satisfactory agreement. Finally, two real case studies are presented. The fragility curves for both the case studies are calculated and discussed. The results encourage the authors to the use of fragility curves based on SMAV model. Additionally, the fragility curves can be easily implemented in seismic risk assessment procedures at urban or territorial scale and, consequently, the proposed procedure may represent a key aspect in the reduction of seismic risk and rationalization of investments for the seismic upgrading of strategic buildings.

The 2017 New Zealand Society for Earthquake Engineering (NZSEE) guidelines for seismic assessment of buildings recommends using Simple Lateral Mechanism Analysis (SLaMA) before implementing numerical analyses. The method and the NZSEE guidelines have been enhanced from the 2006 version, resulting into an efficient procedure, balancing simplicity and accuracy. This paper presents a numerical study, initiated as part of the development of the SLaMA-2017 method, to investigate the accuracy of the analytical approach via comparison with numerical 2D-pushover on 40 RC frames. SLaMA is effective in capturing the plastic mechanism of the frames, including global or soft-story mechanisms. Further-yet-simple refinements of the procedure are suggested. [ABSTRACT FROM AUTHOR]

This study presents the shake-table tests of a 1/5-scaled RC frame retrofitted with RC infill walls. The intensity of input ground motions increased gradually to comprehensively evaluate the structural seismic behavior. We performed a comparison of the results from the RC frame with masonry walls and that with RC walls. The results showed that the presence of RC infills effectively improved the lateral structural stiffness and loading capacity of the frames and reduced their damage and story drift. RC walls acted as the first seismic line of defense, and their failure was dominated by bending failure and concentrated on the low stories. The displacement ductility of the structure decreased with increasing stiffness of the introducing infills. [ABSTRACT FROM AUTHOR]

Within the 2019–2021 research agreement between the Civil Protection Department (DPC) and the Network of University Laboratories for Earthquake Engineering (ReLUIS), the work package WP4 "Seismic Risk Maps—MARS" is specifically devoted to update the 2018 release of the Italian National Seismic Risk Assessment. To this end, the previously considered models of hazard, exposure and vulnerability will be critically reviewed and updated by taking advantage also from the results deriving from other WPs of the DPC-ReLUIS research project. In the present paper some of the most relevant aspects that are being introduced in the development of the new Italian risk maps have been described and shortly analysed. First, a significant upgrade of the vulnerability model implemented in the new version of the platform used for risk calculation (IRMA) is proposed, where reference to the six EMS-98 classes is made also considering regional vulnerability features. Further, empirical data from observed real damage are integrated with results from numerical simulations (mechanical approach), in particular for reinforced concrete buildings. Finally, some special construction types such as schools, churches and bridges are included in order to provide a more comprehensive view of the national risk. [ABSTRACT FROM AUTHOR]