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Heritage is strengthened through proactive actions, known as preventive conservation, that are considered before earthquakes, rather than reactive actions addressed when the emergency situation occurs. Considering that there are several regions around the world with very active seismicity, conservation interventions should guarantee human safety and the improvement of the inhabitant's living conditions while keeping alive the earthen fabric and adobe buildings, thus preserving the lives of the residents but also preserving cultural heritage in the face of earthquakes. The main aim of this paper is to define a comprehensive conservation procedure addressing the preventive conservation of vernacular adobe vaulted houses in Yazd, an Iranian World Heritage property, since 2017. The fundamental phases of this procedure, which this paper's structure is based on, include introducing the case study and addressing the conservation objectives, the assessment of significance and value, the seismic criteria, the conservation strategies, seismic safety assessment, and decision-making on interventions. The comprehensive preventive conservation procedure presented in this paper was determined by relevant conservation criteria, which contributed to an adequate seismic-retrofitted intervention design. This conservation approach requires evaluation of the seismic performance and the buildings' safety, through which the decision regarding intervention could be made. Accordingly, this research also dealt with the seismic safety assessment of an adobe building through numerical research work performed using the software HiStrA Ver.2022.1.6. Based on the numerical results, decisions on the need and on the extent of intervention techniques were addressed. In addition, a comparative study was performed on different seismic strengthening techniques available in the literature to define fundamental conservation criteria. In this way, there are more chances for human lives to be preserved if an earthquake occurs. [ABSTRACT FROM AUTHOR]

Masonry infills are frequently employed as both outer and inner partitions in reinforced concrete (RC) frame structures due to their outstanding characteristics in terms of energy efficiency, fire resistance and sound isolation. However, common construction practice typically involves the mortar connection between masonry infills and RC frames. For this reason, the unforeseen frame-infill interaction takes part under seismic loading, which leads to severe and uncontrollable damage to masonry infills. This interaction also causes damage or even the collapse of the RC frames and thus of the whole structures. The poor performance of infilled RC frame structures in recent earthquake events is a strong motivation for the development of innovative engineering solutions, which aim to mitigate the detrimental effects of frame-infill interaction. This article introduces an innovative decoupling system founded on the concept of decoupling the RC frame from the masonry infill. The decoupling is achieved by inserting elastomeric material between the masonry infill and RC frame. The properly designed decoupling system allows infill activation only at high in-plane drifts. Simultaneously, it provides boundary conditions for seismic loads acting perpendicular to the infill plane. Firstly, the article explains the design of the masonry infill with the decoupling system and its installation. Afterwards, the results of small specimen tests carried out to determine the load-bearing capacity of the decoupling system are presented. Furthermore, the article discusses the findings of an extensive experimental campaign conducted on nine real-size RC frames with decoupled infills subjected to separate and combined in-plane and out-of-plane loadings. In addition to different loading types, various infill configurations are considered – solid infill, infill with centric window, and infill with centric door opening. Finally, the experimental results of RC frames with decoupled infills are compared with the experimental results of traditionally infilled RC frames, which were tested within the framework of the same project. The thorough evaluation and comparison of the experimental findings demonstrate the significant improvement of seismic performance of infilled RC frames if the decoupling system is applied. [ABSTRACT FROM AUTHOR]

The seismic safety margins of seismically isolated bridges have not been thoroughly studied or comprehended due to a lack of actual on-site data observations. This study introduces a newly validated method for the efficient seismic protection of bridges that may be exposed to extremely strong, multidirectional near-source and critical far-source earthquakes. The isolated system was improved by incorporating innovative adaptive horizontal C-multigapped (HC-MG) energy dissipation devices to overcome the safety limitations associated with solely using isolated bridges under seismic loads. The newly developed adaptive C-gapped (ACG) bridge system was systematically validated through extensive experimental seismic tests on bridge models and additional analytical studies. The new ACG bridge system represents an advanced technical solution that integrates the benefits of seismic isolation and energy dissipation. The seismic isolation system for the largescale ACG bridge prototype was designed using double spherical rolling seismic bearings (DSRSB). The seismic performance of the system was enhanced with adaptive HC-MG energy dissipation devices. The improved seismic performance of the system was demonstrated through extensive seismic shaking-table tests on the ACG bridge prototype, simulating selected seismic inputs characteristic of typical near- and far-source earthquakes. [ABSTRACT FROM AUTHOR]

An innovative solution for aluminium-glass partition walls that can withstand seismic actions without damage is presented. The key feature characterising the proposed innovation is a dissipative coupling between the components of the partition wall, i.e., the glass plates and the surrounding aluminium frame, accomplished through the interposition of high-damping rubber pads (HDRPs). Sliding mechanisms between glass panels and the aluminium frame are permitted through specific detailing solutions, which allow the partition wall to be unsensitive to the inter-storey drift imposed by the hosting structure. A detailed discussion of the system conception is illustrated, showing the main intermediate steps that led to the final solution. The implementation of a refined numerical model is illustrated, and its characteristic parameters are calibrated according to a set of experimental tests previously performed on materials and subcomponents. A numerical application to a case study consisting of a partition wall system installed within a three-storey building is provided to assess the performance of the proposed innovative solution under severe earthquakes. [ABSTRACT FROM AUTHOR]

The article studies effect of expedient inter-hole delays on seismic safety of blasting in open pit mining. The actual delays in non-electric initiation systems are measured instrumentally, and the results are processed using computer modeling. The domestic and foreign information on deviation of the actual and design delays is reviewed. The computations prove the increase in the factor of seismic safety in blasting with longer inter-hole delays. Additional instrumental measurements of seismic vibrations should be performed to evaluate actual blast patterns at a full and lab scale, with the analysis of quality of rock fragmentation by blasting. [ABSTRACT FROM AUTHOR]

This paper considering two buildings different in height as a case study to inquiries into the effect of recorded and spectrally matched ground motions (simulated ground motion). Model of structures are developed using design procedure of Chapter 12 of ASCE 7-22 and linear analysis is adopted using requirements of Chapter 16 of ASCE 7-22. In this study, the effects of recorded and simulated ground motions on drift distribution and also floor acceleration are investigated. It could be seen that all of the structures, when subjected to simulated ground motions, give acceptable performance, even though this is not the case with amplitude-scaled ground motions. [ABSTRACT FROM AUTHOR]

To improve the reliability of the incremental dynamic analysis, the Monte Carlo simulation technique is introduced to fully consider the uncertainties in the characteristics of earthquakes. To match the computational efficiency of Monte Carlo simulation, structural seismic responses are calculated by neural networks. To consider the failure risks under 3 safety requirements imposed on the structural seismic performance by the Chinese standard, the equivalent failure probability is employed to compare the safety of 4 different design schemes composed of high-rise frame structures. The workflow of the proposed method is demonstrated by taking the 4 design schemes as examples; good agreement is found between the failure probabilities of the entire structures and their stories with their failure states. Furthermore, the safety of these schemes is compared, and some design advice is discussed.

Heritage is strengthened through proactive actions, known as preventive conservation, that are considered before earthquakes, rather than reactive actions addressed when the emergency situation occurs. Considering that there are several regions around the world with very active seismicity, conservation interventions should guarantee human safety and the improvement of the inhabitant’s living conditions while keeping alive the earthen fabric and adobe buildings, thus preserving the lives of the residents but also preserving cultural heritage in the face of earthquakes. The main aim of this paper is to define a comprehensive conservation procedure addressing the preventive conservation of vernacular adobe vaulted houses in Yazd, an Iranian World Heritage property, since 2017. The fundamental phases of this procedure, which this paper’s structure is based on, include introducing the case study and addressing the conservation objectives, the assessment of significance and value, the seismic criteria, the conservation strategies, seismic safety assessment, and decision-making on interventions. The comprehensive preventive conservation procedure presented in this paper was determined by relevant conservation criteria, which contributed to an adequate seismic-retrofitted intervention design. This conservation approach requires evaluation of the seismic performance and the buildings’ safety, through which the decision regarding intervention could be made. Accordingly, this research also dealt with the seismic safety assessment of an adobe building through numerical research work performed using the software HiStrA Ver.2022.1.6. Based on the numerical results, decisions on the need and on the extent of intervention techniques were addressed. In addition, a comparative study was performed on different seismic strengthening techniques available in the literature to define fundamental conservation criteria. In this way, there are more chances for human lives to be preserved if an earthquake occurs.

3D-Printed Concrete (3DPC) can reduce the consumption of materials, construction costs, and implementation time, as well as increase sustainability. Seismic safety is one of the necessities of any structure in a high earthquake hazard zone. The lack of scientific and engineering studies in this area would highlight the importance of studying seismic safety in 3DPC building structures. This paper is focused on the basic specifications of 3DPC buildings under earthquake excitations. The authors conducted a thorough theoretical study due to the pilot nature of the research. A prescriptive evaluation was conducted based on the existing seismic regulations for similar structures. The main goal of the research was to create the necessary platform for applied studies, which was achieved through theoretical investigations and prescriptive evaluations. For this purpose, the finite element modeling of a 3DPC building with an arch roofing system was implemented and analyzed using ABAQUS software. Based on the main results, the most remarkable weakness of such a structure was the material's poor tension behavior. The arrangement of the internal partitions (infill walls), the shear performance of the walls, and the relative displacement of the components were other effective factors of the 3DPC building under seismic loads. The results showed that the truss-like performance of the arch roof in the considered 3DPC building probably caused the undesirable structural responses under the seismic loads.

An innovative solution for aluminium-glass partition walls that can withstand seismic actions without damage is presented. The key feature characterising the proposed innovation is a dissipative coupling between the components of the partition wall, i.e., the glass plates and the surrounding aluminium frame, accomplished through the interposition of high-damping rubber pads (HDRPs). Sliding mechanisms between glass panels and the aluminium frame are permitted through specific detailing solutions, which allow the partition wall to be unsensitive to the inter-storey drift imposed by the hosting structure. A detailed discussion of the system conception is illustrated, showing the main intermediate steps that led to the final solution. The implementation of a refined numerical model is illustrated, and its characteristic parameters are calibrated according to a set of experimental tests previously performed on materials and subcomponents. A numerical application to a case study consisting of a partition wall system installed within a three-storey building is provided to assess the performance of the proposed innovative solution under severe earthquakes.

Linear and nonlinear analysis methods are defined in the 2018 Turkish Building Earthquake Code (TBDY-2018) to determine the existing earthquake safety of reinforced concrete (RC) buildings. After applying the relevant calculation methods in many buildings, the experience gained was numerically sampled on an existing three-story RC building, and an answer was sought as to whether the linear analysis method is too conservative. When the seismic performance of the RC building was applied using the linear analysis method suggested in TBDY-2018, it was concluded that the building could not provide the 'Controlled Damage (KH)' performance level. On the other hand, as a result of non-linear time history analyses using 11 earthquake records with the assumption of lumped plastic hinges and pushover analyses based on the spread plasticity, it was concluded that the building provides the 'Controlled Damage (KH)' performance level. It has been concluded that the difference in the evaluation is due to the fact that rotation is taken as "zero (0)" at the lower ends of the lowest story columns in the equation (15A.1) in the sub-title of displaced axis rotation in TBDY-2018 Section Annex 15.A.2. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional V-shaped Canyon-Bridge model with three depth-to-half-width ratios is constructed and the theoretical solution of the physical variables of the bridge deck is derived. The wave field of V-shaped canyon under the incident anti-plane shear waves (SH waves) is derived in frequency domain based on the classical elastic wave analytic theory. The time domain wave field of canyon is obtained according to Fourier transform. The bridge displacement input is given according to the wave time-histories. The displacement responses of the bridge deck are derived from the multi-point input of the bridge, and the velocity and acceleration responses are obtained through derivation. The results show that both the amplification effect and the shielding effect of canyon on waves will affect the bridge input and response and are greatly affected by the depth-to-half-width ratio of the canyon. The dangerous location of V-shaped canyon bridges is speculated based on the theoretical results and the actual situation, which provides guidance for the seismic protection of canyon bridges. Kindly check and confirm whether the corresponding author, Mail ID and respective affiliations are correctly identified.The above issues have been checked and confirmed to be correct. Thank you very much. [ABSTRACT FROM AUTHOR]

Background: Recent studies on masonry infills have shown that damages can be more serious when frame and infill are coupled. Although the discussion on out‐of‐plane (OOP) stability and strength of isolated infills is still open, the development of solutions able to assure the decoupling of infill panels respect to structural frame seems to be the most promising in terms of damage prevention of the building. Aim: A system for decoupling the RC frame and the aerated autoclaved concrete (AAC) masonry infill reinforced with textile reinforced mortar (TRM) is presented. The goal is to analyze the potential of this system to face the OOP actions caused by a seismic event. Method: In this system, the frame is free to deform in its plane, without interaction with the AAC infill, which is supported by retaining brackets at the top. These brackets allow relative in‐plane displacements between the RC frame and the masonry infill and avoid OOP overturning of the infill. Results: The paper shows the design of the system and provides an overview of the seismic capacities validated by testing on the system components. Based on the analysis and comparison of the test results, the performance and effectiveness of the proposed system are presented. [ABSTRACT FROM AUTHOR]

This paper has collected more than one hundred papers about resilience at home and abroad, summarised and analysed the meaning and evaluation methods of resilience and then summarised the key issues. Through research on these papers, we found that the current evaluation method for the water supply system seismic resilience is divided into two aspects: on the one hand, it’s based on the seismic performance of water supply system, where the system itself evaluates the resilience absorbs the earthquake resistance level. On the other hand, the assessment is based on the post-earthquake recovery ability of the water supply system, namely the recovery time, recovery degree, recovery path and the resilience level of resources input. Based on past seismic safety of the water supply system and research on post-earthquake recovery ability, the meaning of water supply system in seismic resilience should include two aspects of seismic safety and post-earthquake recovery ability. From using the seismic safety evaluation method also and post-earthquake recovery ability in two angles, this paper gives a comprehensive multiple evaluation index framework of the evaluation model and points out that water system earthquake state resilience evaluative criteria and the requirements of the current seismic code should match.

The severe socio-economic impact of recent earthquakes has represented a tough reality check, further confirming the mismatch between society expectations and reality of seismic performance of modern buildings. Life-safety code-compliant design criteria are not enough when dealing with new structures. To raise the bar in terms of structural safety and overall performance objectives, the renewed challenge is defining high-performance buildings able to sustain a design-level earthquake with minimum disruption of business and limited economic losses. To achieve this goal, alternative strategies might be adopted: (a) implementing more advanced design methodologies, (b) increasing the seismic design level, (c) adopting low-damage earthquake-resistant technologies. However, the common perception is that these strategies would lead to unaffordable costs. To support decision-makers, the paper develops a comprehensive parametric study to compare the cost–benefit of reinforced concrete multi-storey buildings designed for increasing levels of seismic intensities (representing a higher seismicity zone or Importance Class) and according to alternative design approaches (Force-based vs. Displacement-based) and technologies (traditional vs. low-damage). Analytical/numerical investigations are carried out to determine the building performance, and loss assessment analyses are performed to compute the Expected Annual Losses of all the parametric configurations. Results, further elaborated through a machine-learning technique, highlight the convenience of implementing more advanced design methodologies, such as a displacement-based approach allowing for a better control of the building response, and the remarkable benefits of applying low-damage technologies, leading to a very high performance and significantly reduced economic losses (> 50%) for a small increase (< 5–10%) of the initial investment cost. [ABSTRACT FROM AUTHOR]

In this paper we introduce the 3D physics-based numerical simulations (PBS) of ground motion during the Nov 11, 2019, MW 4.9 Le Teil earthquake, which occurred in a low-to-moderate seismicity area in the South-East of France, within the Rhône river valley, which hosts several operating nuclear installations. The numerical code SPEED, developed at Politecnico di Milano, Italy, was used to produce the PBS. After introducing the criteria to construct the numerical model, based on the relatively limited data available, a numerical convergence test was made to identify the frequency range for accurate simulations. Furthermore, the performance of the numerical results against the available strong motion records was assessed quantitatively using Goodness-of-fit (GoF) measures. According to the GoF scores, a good-to-excellent agreement was found on the horizontal components up to 8 Hz, showing that, even without a very detailed 3D numerical model of the medium, that would imply detailed knowledge of the basin shape, of the bedrock-to-basin impedance ratio, as well as of the damping ratio in the basin and its dependence on frequency, the PBS may provide realistic broadband predictions of earthquake ground motion. Nevertheless, as shown by the poorer performance on the vertical component, the high-frequency limitations of PBS, also in relation to the energy radiated by the kinematic source model, is still an issue to be carefully addressed. In spite of these limitations, the results obtained in this work demonstrate that PBS, if suitably calibrated and validated, can be either an alternative or a useful complement to empirical ground motion models, especially in those cases where the region- and site-specific features of ground shaking, including near-source conditions, are typically not accounted for by ergodic empirical models, such as for the seismic risk evaluation of large urban areas and/or of strategic structures, infrastructures and industrial plants. [ABSTRACT FROM AUTHOR]

Florence is known all over the world for its history, monuments, Museums, and artworks. Unfortunately, such precious manufacts are not always adequately protected against natural hazards. Works of art, indeed, are very vulnerable to seismic effects, due to their irregular and slender shapes, and their fragile materials. All these reasons make them vulnerable to seismic events even when they do not achieve a destructive intensity. The current Technical Codes point out such vulnerability, despite providing guidelines not completely adequate to prevent the seismic damage. In this frame, a research activity has started within the Department of Architecture of Florence aimed at investigating the dynamic response of artworks to seismic events, including both simplified form-filling and more detailed Finite Element analyses. In this work, the seismic performance of the marble statue “Oceanus” by Giambologna has been as- sessed by adopting three different analytical models.

The seismic safety assessment of large concrete dams remains a significant challenge in dam engineering, as it requires appropriate analysis methods, modern performance criteria, and advanced numerical models to simulate the dam seismic behavior. This paper presents a method for seismic safety assessment of arch dams based on Endurance Time Analysis (ETA), using tensile and compressive damage results from a robust formulation for seismic analysis considering joint opening/sliding and concrete non-linear behavior (finite element program DamDySSA, under development in LNEC). The seismic performance is evaluated by controlling the evolution of the damage state of the dam, according to predefined performance criteria, to estimate acceleration endurance limits for tensile and compressive damage. These acceleration limits are compared, respectively, with the peak ground accelerations prescribed for the Operating Basis Earthquake (OBE) and Safety Evaluation Earthquake (SEE), aiming to evaluate the dam seismic performance relative to both earthquake levels efficiently, using a single intensifying acceleration time history. The ETA-based method is applied to the cases of Cabril Dam (132 m-high) and Cahora Bassa Dam (170 m-high), confirming its usefulness for future seismic safety studies, while the potential of DamDySSA for non-linear seismic analysis of arch dams is highlighted. [ABSTRACT FROM AUTHOR]

The European building stock presents pertinent issues needing suitable strategies to be solved. In detail, this regards seismic safety and energy efficiency of buildings to ensure more liveable and safe cities, which represents an important goal for modern societies. Energy performance includes both comfort and saving, the latter required for a more responsible resource consumption within the building sector, having a considerable contribution to the total demand. Current strategies do not seem to be able to simultaneously solve such aspects satisfactorily, both for higher economic requirements and poor technical feasibility implied by separated and disharmonious interventions. Thus, a holistic perspective should be adopted to pursue such an ambitious objective, which has recently gained increasing attention among researchers. Current requirements are firstly highlighted to show the need for an integrated approach to building retrofit. Secondly, a critical review of integrated strategies combining seismic and energy refurbishment proposed in the literature is reported. Then, special issues are discussed, including the feasibility of an integrated approach applied to heritage buildings. This study revealed that a fully efficient strategy for integrated retrofit has not still been proposed in the literature and there are several open issues to be solved. However, current solutions may be further developed to improve them and the several options currently available demonstrated the increasing attention and importance of the topic. Finally, concluding remarks on this research topic have been drawn to promote future studies.

Despite the fact that in recent years Portugal has not seen the occurrence of high-magnitude earthquakes, it remains threatened by these events due to its geographic location. Since the 1960s, reinforced concrete has been the most used material for new constructions; however, the historic urban centers are dominated by old unreinforced masonry (URM) buildings, which techniques and construction materials have evolved since the Great Lisbon earthquake that occurred in 1755 (Mw = 8.5). Given the presence of these buildings in areas of significant seismicity, extensive research is needed to assess the seismic risk and define mitigation policies. This kind of studies is often supported by empirical methods and based on expert judgment due to the high variability of the building stock and lack of information. The main purpose of this work is: (i) to provide analytical fragility curves, supported by nonlinear static analysis, for the entire population of old masonry buildings, built before the introduction of the first design code for building safety against earthquakes (RSSCS) in 1958; (ii) define vulnerability curves to be used by the technical community for seismic assessment of pre code URM buildings. The characterization of the building stock geometry and material properties is based on information previously collected, which was essential to define representative archetypes and typologies. [ABSTRACT FROM AUTHOR]

The methods developed by the world community to date to withstand strong natural and induced destructive earthquakes do not effectively reduce material losses and the number of victims. The authors propose for discussion an integrated approach to solving the problem of ensuring seismic safety, based on the use of new important information about the geological conditions for earthquake generation. This involved the use of results of numerical and physical modeling, as well as physical full-scale experiments in the natural fault areas. The paper analyzes the petrophysical conditions of deep-seated frictional processes in coseismic faults, revealed through detailed studies of the fragments of paleoearthquake centers that became accessible after their exhumation from seismic-focal depths of the Earth’s crust. The collected information allowed the authors to clarify with a high degree of certainty the origin and occurrence of seismic motions. This paper presents briefly the results of the medium-term forecast of earthquakes with M≥5.0 as applied to the seismodynamic regime of the Baikal rift zone. The forecast emphasizes the detection of places for 1–11-year earthquake generation cycles.A comprehensive analysis of the collected information made it possible to substantiate the conclusion about an opportunity to prevent earthquake damage by using hydrodynamic damping of seismically hazardous fault segments. In the last section, consideration is being given to one of the most promising methods of such man-made impacts, which uses modern technological advances in drilling deep multil-branch and directionally inclined wells with horizontal deviation. The paper discusses the techniques that make it possible to prevent episodes of unexpected reactivation of fault segments in the form of excitation of earthquakes with M≥6.0. Attention is drawn to conducting tests at selected sites in order to improve the technology as part of the approach to earthquake damping.

To improve the reliability of the incremental dynamic analysis, the Monte Carlo simulation technique is introduced to fully consider the uncertainties in the characteristics of earthquakes. To match the computational efficiency of Monte Carlo simulation, structural seismic responses are calculated by neural networks. To consider the failure risks under 3 safety requirements imposed on the structural seismic performance by the Chinese standard, the equivalent failure probability is employed to compare the safety of 4 different design schemes composed of high-rise frame structures. The workflow of the proposed method is demonstrated by taking the 4 design schemes as examples; good agreement is found between the failure probabilities of the entire structures and their stories with their failure states. Furthermore, the safety of these schemes is compared, and some design advice is discussed. [ABSTRACT FROM AUTHOR]

Although Portugal has not been hit by high‐magnitude earthquakes in recent years, its history is marked by tragic seismic events and it remains susceptible due to its geographical location. The Portuguese building stock is constituted approximately by 45% masonry residential buildings and most were built before the enforcement of the first seismic code in 1958. For several years, structural interventions in these buildings were allowed without the need to assess their seismic vulnerability. In 2019, a new law was approved to regulate the rehabilitation interventions to provide safety and comfort of existing buildings. The seismic assessment of existing buildings became mandatory and based on the procedures and requirements included in NP EN 1998–3: 2017 (Portuguese version of Eurocode 8 – part 3), which establishes the performance requirements and compliance criteria for existing buildings subjected to a certain level of seismic action. According to this normative requirements, analytical seismic vulnerability assessment and reliability‐based analyses were carried out on a large set of masonry buildings representative of the Portuguese housing stock, leading to the development of surrogate and expeditious method for seismic assessment in compliance with the reference method defined in the European standard. The method allows the seismic assessment of masonry buildings with rigid and flexible floors, without explicit numerical analyses, using only geometric parameters and the material properties. Compliance of results assessed by the proposed method and the corresponding values obtained by the code were carried out by confidence tests. [ABSTRACT FROM AUTHOR]

Extensive analytical and experimental research has been done by the authors directed to mitigation of the effects of earthquakes on structures. The research results mainly represent parts of the realized several related international projects. A selected part of the analytical studies directed to comparison between conventional and seismically isolated frame structures is presented in this paper. The responses of the applied newely developed advanced seismic isolation system HC-RMS-GOSEB to the simulated input excitation of three representative earthquakes of intensity 0.50g, have shown that it is very effective for construction of vibro-isolated and seismically resistant buildings, providing activated multistage seismic response and globally optimized seismic energy balance. Its application achieves an increase in the vibration period of the structure, far enough from the dominant period of seismic excitation. The results of the research confirm that this system is a potential solution for achieving low-cost and highly efficient protection of buildings.

The article discusses the issues of protecting the population and territories of the Republic of Uzbekistan from the secondary consequences of natural disasters, in particular from strong earthquakes of magnitude (M≥5). The author noted that strong earthquakes in most cases cause not only primary destruction, but also cause other secondary types of natural and man-made emergencies. Several examples of secondary consequences of strong earthquakes in Uzbekistan and in the world are given. The purpose of the article is to develop innovative approaches to further reduce the secondary consequences of strong earthquakes in Uzbekistan. The existing problems in the field of reducing the consequences of strong earthquakes in the republic, as well as the measures taken to reduce the consequences of strong earthquakes are presented. The article examines the advanced experience of foreign countries (Russia, Kazakhstan, Azerbaijan, Japan, South Korea, Turkey, etc.) in the field of ensuring seismic safety, preparing all segments of the population for correct actions during an earthquake in order to further reduce the secondary consequences of strong earthquakes. At the same time, the authors set out the future prospects for the response (correct actions) of the population and functional services to the seismic forecast in Uzbekistan, proposed a number of correct actions of the population and functional services of the State Service for Prevention and Action in Emergency Situations in accordance with urgent seismic forecasts in tabular form. In the conclusion of the article, in order to further increase the effectiveness of protecting the population and territories from emergencies associated with earthquakes, based on the study of the best practices of foreign countries, outlined innovative approaches to reduce the secondary consequences of strong earthquakes in Uzbekistan.. [ABSTRACT FROM AUTHOR]

On August 21st 2017 an earthquake of magnitude Mw = 3.9 occurred in the Ischia Island (Italy), causing numerous damages to ordinary and monumental buildings and two casualties. Immediately after the earthquake, teams from the Universities of Napoli Federico II and 'Parthenope', carried out inspections on the churches of the island in two phases: the first was developed in the post-emergency and was mainly aimed to assess the overall damage and the usability checks through the A-DC form, issued by the Italian Ministry of Heritage and Cultural Activity and Tourism (MiBACT); the second phase was preparatory to the vulnerability assessment of each church, carried out by filling in the second level form, issued by the Italian Group for the Defence against Earthquakes (GNDT). Based on the available data, a database made of 27 churches was created to individuate the most representative typologies, to perform a territorial vulnerability assessment, to carry out a detailed analysis of the recorded damages and to construct damage probability matrices. Moreover, for a homogenous class of churches, a predictive formulation of the mean damage was assessed and compared with other formulations available in the literature. Finally, simplified methods for assessing the seismic safety of the inspected churches were applied to the database, in order to confirm the homogeneity of the Ischia churches in terms of seismic vulnerability. [ABSTRACT FROM AUTHOR]

Florence is known all over the world for its history, monuments, Museums, and artworks. Unfortunately, such precious manufacts are not always adequately protected against natural hazards. Works of art, indeed, are very vulnerable to seismic effects, due to their irregular and slender shapes, and their fragile materials. All these reasons make them vulnerable to seismic events even when they do not achieve a destructive intensity. The current Technical Codes point out such vulnerability, despite providing guidelines not completely adequate to prevent the seismic damage. In this frame, a research activity has started within the Department of Architecture of Florence aimed at investigating the dynamic response of artworks to seismic events, including both simplified form-filling and more detailed Finite Element analyses. In this work, the seismic performance of the marble statue "Oceanus" by Giambologna has been assessed by adopting three different analytical models. [ABSTRACT FROM AUTHOR]

Storage racks are nonstructural components mainly designed to support the vertical load of goods. During strong external loads such as an earthquake, which acts in the lateral direction of the racks, stored goods become structurally vulnerable. To identify and reinforce the vulnerable parts of storage racks and improve their seismic performance, we developed a viscoelastic damper system with a capacity designed for storage racks. First, we performed an experiment to analyze the behavioral characteristics of a pallet rack — a representative storage rack used for large goods — under vibration. Based on the results of the experiment, we chose the members of storage racks that were vulnerable to vibration. For the proper seismic reinforcement of vulnerable members, we developed a viscoelastic damping system for storage racks by calculating the structural shear force on each floor of the rack and the capacity of the damper to distribute the shear force. First, three viscoelastic dampers of different capacities were fabricated using a viscoelastic material and subjected to cyclic loading tests to evaluate their mechanical performance. We determined the position on which the damper should be placed to improve the rack's seismic performance by considering the shear force on each floor of the storage rack and its operational characteristics. Finally, we conducted a shaking table test to verify the new viscoelastic damper system. The system improves the seismic performance of storage racks by controlling their elastic and permanent deformations. [ABSTRACT FROM AUTHOR]

Within this current study, in order to be safe of school buildings against an earthquake, shear wall ratio, must have been a plan, was determined depending on floor type. In order to determine these approach, three types of model building formwork plans with 4, 6 and 8 classrooms were selected. Shear wall- frame systems have been created by placing 4 reinforced concrete shear walls symmetrically on both sides of each of the 3 selected formwork plans. Each of the 3 types of selected formwork plans were modeled as 2, 3, 4 and 5 stories. Each of the model buildings was built for 2 types of material combination. Thereby, a total of 24 types of school buildings were taken into account in the calculations. Performance evaluation of the 24 model school buildings produced was made by using nonlinear analysis method. The smallest reinforced concrete shear wall dimensions, provided the predicted performance level, are obtained by increasing by 5 cm the reinforced concrete shear walls in both directions. This process was carried out until each of the selected 24 model buildings provided the minimum target performance levels based on the probability of exceeding occurrence. Shear wall dimensions were determined by dividing specified curtain wall dimensions into floor areas.These shear wall ratios depend on floor type.

Earthquake emergency treatment is a key technology to solve the last 1 km of earthquake early warning applications, and it has obvious effects on preventing gas accidents in earthquakes. As a communication technology, NB-IoT has technical advantages such as low cost, low power consumption, and wide coverage compared to traditional wireless communication methods such as 4G. In recent years, NB-IoT communication technology has been widely promoted in the field of Internet of Things as the latest technology, but there is no public application in the field of earthquake early warning. This article introduces a new gas earthquake emergency treatment system based on NB-IoT, discusses the principle and basic composition of the gas earthquake emergency treatment device based on NB-IoT, and analyzes and compares it with the existing similar devices. The key points in the research and development process are aimed to promote solutions based on NB-IoT to realize gas earthquake emergency disposal system, and provide technical guarantee for gas earthquake safety. [ABSTRACT FROM AUTHOR]

This paper considers the potential of designing and constructing floor slabs taking into account three aspects of major importance: flexibility-adaptability, energy efficiency and seismic safety. Currently traditional reinforced concrete floor slabs at least 20 centimetres thick are still designed and built. Such practice has no justification, as thick concrete floor slabs hinder architectural creativity as well as all the other aforementioned aspects. In this paper, the authors analyse and demonstrate the simultaneous correlation between flexibility-adaptability, energy efficiency, seismic safety and the mass of the floor slabs in residential buildings. Massive floor slabs limit the distance between load-bearing walls and consequently the adaptability of residential space. A large mass directly intensifies the seismic forces it induces. Thick concrete slabs have high heat capacity, as they have high mass and volume. The solution to floor slabs which satisfy all three aspects is to design and build them as waffle slabs. These two-way spanning concrete slabs have low mass, are rigid and can span the distance of more than 10 metres between two load-bearing walls.The authors of this paper suggest that floor slabs conform to the limitation in mass provided in this paper under Eq. (5) and (6). By applying this principle, architects would be able to design more flexible, adaptable, energy efficient, and seismically safe living spaces.

In the part 2 of the study [Ruzhich, Kocharyan, 2017, we aimed at identifying the elements of paleoearthquake sources in the crust, which formed at the hypocentral depths in the exhumed Primorsky segment of the ancient collisional suture. The study area covered the southeastern margin of the Siberian craton (Pribaikalie, East Siberia). Slickensides, pseudo-tachyllite (basaltic glass) and other petrological evidence of intensive tectonic movements were sampled. The structure of the deep segments of the collisional suture were reconstructed from on the data on coseismic ruptures and faults, and the PT parameters were estimated. In the past decades, similar research problems were actively investigated (e.g. [Sibson, 1973; Byerlee, 1978; Morrow et al., 1992; Hodges, 2004; Kirkpatrick et al., 2012). In Russia, the interest in studying geological and geophysical features of the deeply denuded areas in ancient faults is still limited [Sherman, 1977; Ruzhich, 1989, 1992, 1997; Savel’eva et al., 2003; Ruzhich et al., 2015; Kocharyan, 2016. The deeply denuded Primorsky segment of the collisional suture of the Siberian Craton underwent the geological evolution of a billion years. In the analysis, we used additional geological data from the petrology studies of the Main Sayan fault zone and other exhumed fault segments, including the seismogenerating faults in the Mongolia-Baikal region [Zamaraev, Ruzhich, 1978; Zamaraev et al., 1979; Ruzhich et al., 2009. From the PT conditions for the occurrence of the slickensides, pseudo-tachylyte, and the Primorsky segment structure, the 40Ar/39Ar method estimated the age of the slickensides containing tourmaline at 673±4.8 Ma, which may correspond to the Neoproterozoic stage of the breakdown of the megacontinent Rodinia. Another dating, 415.4±4.1 Ma, obtained for the muscovite sample from a decompressional rupture, refers to the Early Paleozoic stage in the development of the collisional suture, when accretion of the Siberian Craton and the Olkhon terrain took place [Donskaya et al., 2003; Fedorovsky et al., 2010. Based on these ages and other available petrological data, the depths of the heterochronous systems of coseismic ruptures were estimated:18 km in the Neoproterozoic, and12 km in the Middle Paleozoic stage of the seismotectonic evolution of the crust in Pribaikalie. The deep paleoseismological settings need to be further investigated in order to more thoroughly clarify the physical and chemical conditions that contributed to the occurrence of the ancient and recent sources of strong earthquakes in the deep segments of faults in the crust. Such information is a prerequisite for further progress towards resolving the problems of securing seismic safety in various regions.

Le murature portanti realizzate con materiali lapidei naturali possono costituire una risorsa per la ricostruzione di aree devastate da eventi sismici nella misura in cui si chieda di recuperare,oltre ad una maggiore sicurezza antisismica, anche un’identità storico-tipologica e tecnologica del tessuto urbano, unitamente alla possibilità di rilanciare le attività edilizie artigianali delle economie locali, altrimenti tagliate fuori dal processo di ricostruzione spesso basato sull’importazione di tecniche costruttive avulse dal contesto in cui si affermano.Se da un lato l’emergenza impone l’uso di sistemi costruttivi a secco solitamente basati su legno e acciaio, che consentono in tempi rapidi di dare ricovero a persone e cose, appare tuttavia evidente chequeste, unitamente al cemento armato,non possono essere imposte come la soluzione valida ovunque e comunque per la ricostruzione di antichi borghi completamente distrutti,dei quali deve essere tramandata la memoria storica anche in base alle recenti direttive ministeriali. Nella memoria si indagano sinteticamente le tecnologie costruttive in muratura ammesse dalle normative antisismiche, alla luce del fatto chele stesse offrono interessanti prestazioni acustiche ed energetiche, grazie all’elevata massa ed inerzia termica, aspetti anch’essi oggetto di specifiche normative cogenti. --- Natural stone masonry is a fundamental resource for buildings reconstruction or renovation in areas devastated by seismic events, in order to recover the historical-typological identity of Central Italy urban landscape. As a matter of facts, this kind of building material,united with the new seismic safety technologies, allows to relaunch local handcrafts, otherwise cut off from the reconstruction process based on foreign constructive techniques. Whereas, on the one hand, emergency requires the use of wood and steel building systems or reinforced concrete, allowing rapid provision of shelter to people and things, it is evident, however, that it is not the ideal solution for a new concept of reconstruction of completely destroyed ancient villages and cultural heritages, also according to recent ministerial directives. In this paper, the building technology based on natural stone masonry, allowed by the seismic prevention regulations, are synthetically investigated in terms of both structural and technological properties, such as seismic safety, acoustic and energy performances, according to the recent building standards and regulations.

The paper discusses the basic principles underlying a new approach to the control of seismic activity in tectonic fault zones. A key component of the approach is the use of controlled man-made impacts on highly stressed fault segments. The applicability of the approach was verified in field experiments on seismically active fault segments of the Baikal rift zone and collision structures of Mongolia. The paper reports the most striking examples of applying man-made pulsed vibrational impacts to highly stressed fault segments in combination with controlled fluid injection into deep wells. The results of impacts on the studied fault segments are discussed in the light of new geological data on physicochemical processes in the zones of ancient seismically active faults and recent advances in deep drilling for hydrocarbon exploration and production. A justification is provided for the concept of controlled shear stress relaxation in potentially hazardous fault segments showing the signs of earthquake preparation. The possible implementation of the proposed concept in the near future is discussed. [ABSTRACT FROM AUTHOR]

Summary: There is a growing tendency toward the performance‐based design of tall buildings, where any assessment using response history analysis requires a set of ground motion (GM) records. This paper considering a tall building as a case study investigates how judgment on the seismic safety of the structure is affected by the use of recorded or spectrally matched GMs. Three model structures are developed: (a) using conventional design procedure of Chapter 12 of ASCE 7‐16; (b) adopting linear analysis requirements of Chapter 16 of ASCE 7‐16; (c) designing for service‐level design earthquake of Los Angles Tall Building Structural Design Council (LATBSDC) procedure. It is shown that all of the structures give acceptable performance when subjected to simulated GMs, although this is not the case for amplitude‐scaled GMs based on ASCE 7‐16 and LATBSDC. Finally, to have an objective assessment of performance, independent of GM types, incremental dynamic analysis is employed to derive fragility and mean annual rate of exceeding (MAR). Results show that for anticipated drifts at Maximum Considered Earthquake (MCE) level, the structures provide acceptable MAR at the fundamental period. However, for the higher modes including the second and third periods, MAR values become acceptable only at drifts as large as 0.085. [ABSTRACT FROM AUTHOR]

Residual risk exists in our buildings even if they were designed in conformance with modern codes of practice. Various approaches have been implemented or proposed in the last decade for setting risk-based performance requirements for seismic design of building structures. However, there is insufficient consideration about the aggregated risk for society, which could be significant especially for a densely populated metropolitan city. This paper introduces a rational and universal approach for evaluating the adequacy of structural safety requirements by comparing societal risk functions based on probabilistic loss assessment with a proposed regulatory requirement that aims to limit the mortality rate to "as low as reasonably practicable (ALARP)". The proposed approach is then applied to Melbourne, Australia, in a case study, which shows that the earthquake fatality risk for the society appears to be unacceptable. The outcome can be used for justification of a seismic retrofitting policy or a required change of the design code level. The proposed scheme is also applicable to other natural hazards and for safety engineering applications generally. [ABSTRACT FROM AUTHOR]

The damages and losses caused by dam failure are significant. Currently, the seismic safety of dams is well established. However, a study concerning the seismic safety of dam-relevant structures is necessary. Occasionally, dams may withstand an earthquake; however, they are often unable to operate after the quake due to malfunctioning dam-relevant structures. Furthermore, the collapse of such structures could lead to a dam failure or cause considerable losses to the society downstream as well. Therefore, the seismic safety of dam-relevant structures cannot be neglected, and such safety precautions must be conducted properly. The main goal of this research is to evaluate the seismic safety of a dam spillway in Northern Thailand and to ensure that it can operate normally after an expected large earthquake. First, a representative dam-relevant structure is selected based on the availability of data and its importance. Afterward, the performance goal of a representative structure will be established upon its importance, expected performance, and ground motion level. For example, all structural components must be intact, and the uncontrollable release of reservoir water must not take place during and after the maximum considered earthquake (MCE). The seismic analysis of a representative structure is then performed using a numerical simulation. Finally, based on the results, suggestions are made regarding the seismic safety of the representative structure. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to evaluate the seismic safety of water supply pipeline networks. It proposes a definition of seismic safety of water supply pipeline networks based on research results regarding seismic damage prediction and functional failure analysis of such networks, referring to the basic concept of safety. The definition proposes restrictive criteria and finality criteria. This paper establishes a division standard for the seismic safety level of a water supply pipeline networks. It establishes a preliminary evaluation method and model of the seismic safety of the water supply pipeline networks in combination with a seismic damage prediction model and functional failure analysis model. It makes it possible to evaluate whether a water supply pipeline networks meets the current seismic specification requirements. This evaluation method can also provide a scientific basis for urban earthquake disaster reduction and reconstruction. Finally, with this method, the water supply pipeline networks seismic safety is evaluated for Harbin and corresponding suggestions are put forward. [ABSTRACT FROM AUTHOR]

Within the scope of this study, an approach has been proposed to practically determine seismic safety of existing school buildings. For this purpose, three types of model building formwork plans with 4, 6 and 8 classrooms were selected. Shear wall-frame systems have been created by placing 4 reinforced concrete shear walls symmetrically on both sides of each of the 3 selected formwork plans. Each of the 3 types of selected formwork plans were modelled as 2, 3, 4 and 5 stories. Thereby, a total of 12 types of school buildings were created. The smallest reinforced concrete shear wall dimensions, provided the predicted performance level, are obtained by increasing by 5 cm the reinforced concrete shear walls in both directions. This process was carried out until each of the selected 12 model buildings provided the minimum target performance levels, is specified in Turkish Earthquake Code (TEC) [1], based on the probability of exceeding occurrence. The limit values of proposed practical approach are obtained by using model building analyses. In order to determine the consistency of the limit values in this proposed approach, 70 project data of framed and shear wall-framed systems school buildings where in Isparta region are obtained. The results obtained with the proposed approach were compared with the results of the detailed solutions in accordance with the TEC [1] guidelines. [ABSTRACT FROM AUTHOR]

Today, many important concrete face rockfill dams (CFRDs) have been built on the world, and some of these important structures are located on the strong seismic regions. In this reason, examination and monitoring of these water construction's seismic behaviour is very important for the safety and future of these dams. In this study, the nonlinear seismic behaviour of Ilısu CFR dam which was built in Turkey in 2017, is investigated for various reservoir water heights taking into account 1995 Kobe near-fault and far-fault ground motions. Three dimensional (3D) finite difference model of the dam is created using the FLAC3D software that is based on the finite difference method. The most suitable mesh range for the 3D model is chosen to achieve the realistic numerical results. Mohr-Coulomb nonlinear material model is used for the rockfill materials and foundation in the seismic analyses. Moreover, Drucker-Prager nonlinear material model is considered for the concrete slab to represent the nonlinearity of the concrete. The dam body, foundation and concrete slab constantly interact during the lifetime of the CFRDs. Therefore, the special interface elements are defined between the dam body-concrete slab and dam body-foundation due to represent the interaction condition in the 3D model. Free field boundary condition that was used rarely for the nonlinear seismic analyses, is considered for the lateral boundaries of the model. In addition, quiet artificial boundary condition that is special boundary condition for the rigid foundation in the earthquake analyses, is used for the bottom of the foundation. The hysteric damping coefficients are separately calculated for all of the materials. These special damping values is defined to the FLAC3D software using the special fish functions to capture the effects of the variation of the modulus and damping ratio with the dynamic shear-strain magnitude. Total 4 different reservoir water heights are taken into account in the seismic analyses. These water heights are empty reservoir, 50 m, 100 m and 130 m (full reservoir), respectively. In the nonlinear seismic analyses, near-fault and far-fault ground motions of 1995 Kobe earthquake are used. According to the numerical analyses, horizontal displacements, vertical displacements and principal stresses for 4 various reservoir water heights are evaluated in detail. Moreover, these results are compared for the near-fault and far-faults earthquakes. The nonlinear seismic analysis results indicate that as the reservoir height increases, the nonlinear seismic behaviour of the dam clearly changes. Each water height has different seismic effects on the earthquake behaviour of Ilısu CFR dam. In addition, it is obviously seen that near-fault earthquakes and far field earthquakes create different nonlinear seismic damages on the nonlinear earthquake behaviour of the dam. [ABSTRACT FROM AUTHOR]