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The purpose of this paper is to present a probabilistic assessment and verify the effectiveness of seismic improvement schemes against earthquake, blast and progressive collapse. The probabilistic analysis is performed by taking into account the uncertainties in loading such as planar configuration and amplitude of the blast loading. A standard Monte Carlo (MC) simulation method is employed to generate various concepts of the uncertain parameters within the problem. For a given concept, various local dynamic analyses are performed within a certain range of distance, in order to quantify and locate the damage induced by impact wave on structural elements. In the next step, a limit state analysis is performed in order to investigate whether a progressive collapse mechanism forms under the acting loads or not.

( | ) and ( | ) are blast fragility and seismic fragility, respectively; ( ) and ( ) are annual occurrence rate of earthquake and blast, respectively. The purpose of the current study is to calculate for the primary structure as well as the retrofitted structure. Annual occurrence rate of earthquake can be calculated by using probability seismic hazard analysis for the site of interest, where the structure is located. In this paper, blast fragility and seismic fragility are defined rather differently; in other words, seismic fragility is defined as the probability of structural collapse given a specified level of seismic intensity whereas blast fragility is defined as the probability of collapse given that a significant blast event takes place. Both blast and earthquake loading conditions involve the activation of energy dissipation mechanism and, as a consequence, both can be resisted employing ductility enhancing techniques, such as column wrapping or jacketing and steel bracing.

The current paper aims to present a probabilistic assessment of progressive collapse under blast and earthquake loads. Non-dependent and incompatible events are considered to obtain a general rate of collapse. Finally, probabilistic collapse rate was obtained for a moment frame before and after modifying with convergent steel brace (CBF). The purpose of doing so is to investigate whether seismic improvement schemes can reduce collapse risk of different critical events or not.

Objective of the present work is to present a methodology for calculating the annual risk of collapse for a civil structure subjected to both seismic and blast loads, using a bi-hazard approach. Given that a blast event takes place, the probability of progressive collapse is calculated using a MC simulation procedure. The simulation procedure implements an efficient non-linear limit state analysis, formulated and solved as a linear programming problem. The probability of collapse caused by an earthquake event can be calculated by integrating the seismic fragility of the structure and the seismic hazard for the site.

This paper aims to improve the seismic building design (SBD) work process for Malaysian Government projects.

Semi-structured interviews were virtually conducted to a small sample size of internal and external stakeholders from the Malaysian Government technical agency. There were seven of them, comprising Structural Engineers, an Architect, a Quantity Surveyor and consultants-linked government projects. The respondents have at least five years of experience in building design and construction.

The paper evaluates the current SBD work process in the government technical agency. There were four main elements that appear to need to be improved, specifically in the design stage: limitations in visualization, variation of works, data management and coordination.

This study was limited to Malaysian Government building projects and covered a small sample size. Therefore, further research is recommended to extend to other government agencies or ministries to obtain better results. Furthermore, the findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.

The findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.

This study was limited to government building projects and covered a small sample size. Therefore, further research is recommended to extend to other government agencies or ministries to obtain better results. Furthermore, the findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.

This study provides an initial step to introduce the potential of building information modeling for SBD in implementing Malaysian Government projects. It will be beneficial both pre-and post-disaster and is a significant step toward a resilient infrastructure and community.

The purpose of this paper is to examine the effectiveness of building codes in earthquake risk mitigation in Taiwan.

Using probabilistic risk analysis tools with available data, this study assesses the exceedance probability of extensive damage limit for general buildings in their 50‐year useful lives. The buildings were classified into 15 categories according to their construction materials and building height. Then, the effects of construction materials, building height and construction years are detected.

The exceedance probabilities of extensive damage limit for all of the investigated buildings in their 50‐year useful lives are on the order of 10⁻². The effect of construction materials and building height on seismic risk of buildings is decreasing with the development of a seismic design code. Significant discrepancy of seismic risk still exists among some buildings.

Seismic risk analysis requires quite restrictive statistical idealizations for the relevant probabilistic terms in the mathematical formulation. The problem of imperfect simplification and lack of sufficient empirical data has shown the research needs for improvements of seismic risk assessment. The questions of what constitutes acceptable risk for various performance levels and how safe is safe enough remain context‐specific.

Although probabilistic risk analysis provides a tool for quantifying the probability of structural failure, current earthquake‐resistant design procedures do not relate performance levels to probability. The paper explores some probability information for current earthquake‐resistant design for general buildings during their 50‐year useful lives and the information may provide some valuable information for future code calibration.

The purpose of this study is for a higer sustainability of the historic towns and centres. The task of the society is to minimize risk and guarantee maximun safety within the territory while safeguarding the natural as the built landscape. With these sometimes unfortunate outcomes in mind, the society continue to promote “informed planning” hoping to achieve ever grater sustainability and respect for the extant, but, in practice, what the society have done amounts to very little. Indeed, today’s historic city centrers remain neglected and are increasingly “unsafe”.

In the course, Italy introduced a set of regulations in an attempt to construct, transform, conserve and exploit the potential of historic cities. Unfortunately, the results were not outstanding and today we need to rethink their approach if we are to reverse the abandonment of historic centers and make those “safe” again. In an effort to understand if what was hitherto put in place is sufficient or if new strategies are called for, we have reviewed the technical measures issued. In a large number of cases, restoration only increased their fragility, whereas in many others, especially concerning small centers with traditional economies, no rehabilitation work was ever attempted, not even essential maintenance work, and thus their functional and physical obsolescence became manifest.

The variegated and complex fragility of such centers requires forms of planning that can take account of the environment, deploy city-planning measures and undertake structural and architectural adaptation. If regeneration is to lead to a “comprehensive and integrated vision” for solving urban problems, economic, physical and social improvement and appropriate environmental conditions for an area subject to transformation, it will require new national and local action policies able to guarantee physical safety, the conservation of cultural values and the social and economic regeneration of such centers within a framework of policies for equilibrated urban development.

The processes of repurposing/revamping and giving leverage to historic centers must make use of multidisciplinary approaches ranging from conservation needs to overall regeneration needs. Therefore, new formulas are needed to enable us to combine conservation based on protective constraints with formulas for rehabilitation, reuse and performance improvement that are couched less in terms of sustainability, and more in terms of profitability, according to the principle – repeatedly voiced in international forums – that assets are also economic resources. Therefore, it will be necessary to proceed carefully, by drawing up a program of territorial development strategies with due guarantees of feasibility and economic growth prospects.

An appropriate regulatory framework is certainly necessary for the regeneration of historic towns and centers but an even more important role should be played by projects that optimize the use of resources if we are to ensure that financing will be managed correctly and a connection will be created – given the discontinuity represented by new constructions – between what remains of extant historic and contemporary architecture and construction. In this context, contemporary architectural design and urban planning can help meet the continued requests for the refurbishment of consolidated cities and the reconstruction of earthquake-stricken towns.

Rehabilitating center is not a cultural luxury but a necessity that springs from the need to economize territorial and economic resources. Consequently, a methodology should be formulated to produce, in each specific case, a design jointly drawn up by town planners, architects, urban redevelopment experts, structural engineers and with the participation of many other specialist figures, such as economists, sociologists, geologists and engineering physicists.

This paper provides a multidisciplinary vision on regeneration.

The purpose of this paper is to examine why building owners are often reluctant to adopt adequate mitigation measures despite the vulnerability of their buildings to earthquake disasters, by exploring the economic-related barriers to earthquake mitigation decisions.

A case study research method was adopted and interviews chosen as the method of data collection.

Critical economic-related impediments that inhibited seismic retrofitting of earthquake-prone buildings were revealed in this study. Economic-related barriers identified include perception about financial involvement in retrofitting, property market conditions, high insurance premiums and deductibles, and the high cost of retrofitting. The availability of financial incentives such as low interest loans, tax deductibles, the implementation of a risk-based insurance premium scale and promoting increased knowledge and awareness of seismic risks and mitigation measures in the property market place are likely to address the economic-related challenges faced by property owners when undertaking seismic retrofitting projects. The provision of financial incentives specifically for seismic retrofitting should be introduced in policy-implementation programme tailored to local governments’ level of risks exposure and available resources.

The recommendations provided in this study suggest strategies and answers to questions aimed at understanding the types of incentives that city councils and environmental hazard managers should focus on in their attempt to ensure that property owners actively participate in earthquake risk mitigation.

This paper adopts a holistic perspective for investigating earthquake risk mitigation by examining the opinions of the different stakeholders involved in seismic retrofit decisions.

In the absence of random variables, random variables are generated by the Monte Carlo (MC) simulation method. There are some methods for generating fragility curves with fewer nonlinear analyses. However, the accuracy of these methods is not suitable for all performance levels and peak ground acceleration (PGA) range. This paper aims to present a method through the seismic improvement of the high-dimensional model representation method for generating fragility curves while taking advantage of fewer analyses by choosing the right border points.

In this method, the values of uncertain variables are selected based on the results of the initial analyses, the damage limit of each performance level or according to acceptable limits in the design code. In particular, PGAs are selected based on the general shape of the fragility curve for each performance limit. Also, polynomial response functions are estimated for each accelerogram. To evaluate the accuracy, fragility curves are estimated by different methods for a single degree of freedom system and a reinforced concrete frame.

The results indicated that the proposed method can not only reduce the computational cost but also has a higher accuracy than the other methods, compared with the MC baseline method.

The proposed response functions are more consistent with the actual values and are also congruent with each performance level to increase the accuracy of the fragility curves.

This research study focuses on investigating the seismic performance of non-straight beams in steel structures and exploring the mechanism by which plastic hinges are formed within these beams. The findings contribute to the understanding of their behaviour under seismic loads and offer insights into their potential for enhancing the lateral resistance of the structure. The abstract of the study highlights the significance of corners in structural plans, where non-coaxial columns, diagonal elements or beams deviating from a straight path are commonly observed. Typically, these non-straight beams are connected to the columns using pinned connections, despite their unknown seismic behaviour. Recognizing the importance of generating plastic hinges in special moment resisting frames and the lack of previous research on the involvement of these non-straight beams, this study aims to address this knowledge gap.

This study examines the seismic behaviour and plastic hinge formation of non-straight beams in steel structures. Non-straight beams are beams that connect non-coaxial columns and diagonal elements, or deviate from a linear path. They are usually pinned to the columns, and their seismic contribution is unknown. A critical case with a 12-m non-straight beam is analysed using Abaqus software. Different models are created with varying cross-section shapes and connection types between the non-straight beams. The models are subjected to lateral monotonic and cyclic loads in one direction. The results show that non-straight beams increase the lateral stiffness, strength and energy dissipation of the models compared to disconnected beams that act as two cantilevers.

The analysis results reveal several key findings. The inclusion of non-straight beams in the models leads to increased lateral stiffness, strength and energy dissipation compared to the scenario where the beams are disconnected and act as two cantilever beams. Plastic hinges are formed at both ends of the non-straight beam when a 3% drift is reached, contributing to energy damping and introducing plasticity into the structure. These results strongly suggest that non-straight beams play a significant role in enhancing the lateral resistance of the system. Based on the seismic analysis results, this study recommends the utilization of non-straight beams in special moment frames due to the formation of plastic hinges within these beams and their effective participation in resisting lateral seismic loads. This research fills a critical gap in understanding the behaviour of non-straight beams and provides valuable insights for structural engineers involved in the design and analysis of steel structures.

The authors believe that this research will greatly contribute to the knowledge and understanding of the seismic performance of non-straight beams in steel structures.

The purpose of this paper is to explore the changes in commercial office occupiers’ preferences in their building choice as a result of a recent natural disaster which triggered policy changes in building safety.

This study follows a qualitative research design comprising semi-structured one-on-one interviews with 24 property professionals (commercial leasing agents and property managers) in Auckland, New Zealand. A thematic analysis was employed for identifying, analysing and reporting themes emerged within data.

Tenants across New Zealand now incorporate earthquake issues in their leasing decisions. Most tenants are familiar with the impending policy changes related to earthquake-prone buildings. The degree to which building standards are incorporated into office occupiers’ choice varies with the size of the organisation and their willingness to invest in their corporate social responsibility. A certain level of overreaction was observed in tenants’ behaviour in the face of risk and uncertainty following the earthquakes. However, risk appears to be subsiding and emphasis is placed on availability of space in desirable locations.

The findings are limited due to a non-random sample selection and a small sample size. Further quantitative research is required to determine if office tenants place a premium on occupying seismically safe buildings since forthcoming regulatory changes have been announced.

This study provides evidence that imminent building policy changes are efficient in raising public awareness and informing perceptions of potential losses following a recent natural disaster event. Building owners can potentially capitalise on tenants’ desire to occupy high quality space.

This is the first study that develops the knowledge base identifying the perceptions of tenants about seismic safety of buildings since the Canterbury earthquakes. The study also contributes to the literature on the market effect of policy changes triggered by a focusing event.

The purpose of this paper is to provide the research and practising engineers with insight on the benefits of using low‐yield point steel with respect to ordinary steel as a construction material for shear wall panels. The paper seeks to focus on the behaviour of such panels when installed in new or existing structures in order to improve their seismic performance.

Finite element models are applied in order to approximate the structural response of low‐yield steel panels, used for seismic applications. Owing to the specific characteristics of the problem at hand, geometric and material nonlinearities have to be accurately considered. For comparison reasons, low‐yield point steel and ordinary steel are considered as construction materials for the aforementioned panels. The paper examines both the case of “pure shear” steel panel and also the more realistic case that the panel is encased in the surrounding frame.

The paper reaches a number of interesting conclusions. The beneficial behaviour of low‐yield steel panels with respect to ordinary steel panels is verified. Comments are made distinguishing the differences in the behaviour of panels surrounded by strong elements (“encased” panels) compared with that of panels submitted to pure shear. Finally, the improved seismic behaviour of existing structures retrofitted by shear wall panels is verified.

The paper exhibits numerically the advantages of low‐yield point steel with respect to ordinary steel as a construction material for panels and, second, contributes to the comprehension of the realistic panel behaviour of encased panels. More specifically, the paper focuses on the differences in the behaviour of encased steel panels with respect to the “pure shear” steel panels.

The purpose of this paper is to investigate a reinforced concrete multi-storey building with dissipative structural walls. These walls can improve the behaviour of a tall multi-storey building. The authors’ main objective is to evaluate the damage of a building with dissipative walls in comparison with that of a building with solid walls.

In this paper, a comparative nonlinear dynamic analysis between a building with slit walls and then the same building with solid walls is performed by means of SAP2000 software and using a layer model. The solution to increase the seismic performance of a building with structural walls is to create slit zones with short connections in to the walls. The short connections are introduced as a link element with multi-linear pivot hysteretic plasticity behaviour. The hysteretic rules and parameters of these short connections were proposed by the authors and used in this analysis. In this study, the authors propose to evaluate the damage of a building with reinforced concrete slit walls with short connections using seismic analysis.

Using the computational model created by the authors for the slit wall, a seismic analysis of a multi-storey building with slit walls was done. From the results obtained, the advantages of the proposed model are observed.

Using a simple computational model, created by the authors, that consume low processing resources and reduces processing time, a nonlinear dynamic analysis on high-rise buildings was done. Unlike other studies on slit walls with short connections, which are focused mostly on the nonlinear dynamic behaviour of the short connections, in this paper the authors take into consideration the whole structural system, wall, connections and frames.