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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.

Earthquakes are a serious threat to life; they claim many casualties and cause huge damage to people's properties. Seismic design provisions are added to building codes in response to the lessons learned from past earthquakes. However, despite all successes, many challenges are still faced and there are still deficiencies, especially in the field of architectural non‐structural components (ANSCs). In spite of their significance in the seismic performance of the building, ANSCs are mostly neglected from the viewpoint of seismic design. The purpose of this paper is to explain a proper state for the seismic consideration of ANSCs in the designing and construction process.

The key aim of this research is explaining a proper state for the seismic consideration of ANSCs in designing and construction process. For this purpose, first, their state is analyzed based on the conventional seismic design and construction process. Then, the insufficiencies of this approach are discussed through studying the consequences in the past earthquakes. Finally, based on the results obtained, the article tries to offer useful strategies to bring the potential threats of ANSCs to minimum.

It is found that ANSCs are considered only in a very small part of the design and construction process. In most cases, their executed details are allocated to a minor part of the design process or left to be chosen in the last stage of construction, as finishing details. As a result, despite all code provisions and practical guidelines, we still see many damages to and from ANSCs. The paper shows that the only way that the success of ANSCs' seismic restraints can be anticipated is by considering them in all stages of the design and construction process. To achieve this goal, collaboration is needed throughout all parts of the design and construction process, namely an interactive system design.

The paper, from the viewpoint of the design process, analyzes the seismic consideration of ANSCs, offering a new model for placing these components in a systematic design and construction process.

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.

Until the Loma Prieta earthquake of 17 October 1989, also known as the “World Series earthquake” or the “San Francisco earthquake,” many of us may have considered earthquakes a remote danger. But instantaneous television transmission from the interrupted World Series game and frightening images of the collapsed Cypress Viaduct and the burning Marina district transformed this incident from a distant disaster into a phenomenon that touched us all. The Loma Prieta earthquake was followed in December 1990 by the inaccurate but widely publicized New Madrid earthquake prediction. Despite its inaccuracy, this prediction alerted the public to the fact that the largest earthquake ever to have occurred in the United States occurred not in California or Alaska, but in Missouri, and that a large earthquake could occur there again. Americans are discovering that few places are immune to the possibility of an earthquake.

The purpose of this paper is to establish the horizontal displacement angle limit values under different performance level, use damage as the quantitative index of performance level and determine the design principle of the RACFST column for performance-based seismic fortification target based on the damage.

The paper is based on the seismic performance test of the RACFST column.

First, three-level seismic are introduced into the performance design foundation of the RACFST column. Second, the performance level of the RACFST column is divided into five grades: normal use, temporary use, use after repair, life safety and prevention of collapse. Third, the seismic performance targets of RACFST columns are divided into four categories: unacceptable situation, basic performance target, important performance target and special performance target.

The initial damage of the recycled aggregate occurs in the process of crushing and screening, and the damage evolution and development of the RACFST column occur under cyclic load. This is one of the problems that should not be avoided in the design of the seismic performance of the RACFST column. New levels are introduced in the performance design foundation of the RACFST column.

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic damage that may occur to traditional structures of NPPs during their service. This is to promote the passive safety concept in the structural design of AP1000 NPPs against earthquakes.

In conjunction with seismic isolation, tuned-mass-damping (TMD) is integrated into the seismic resistance system of AP1000 NPPs to satisfy the multi-functional purposes. The proposed base-isolation-tuned-mass-damper (BIS-TMD) is studied by comparing the seismic performance of NPPs with four different design configurations (i.e. without BIS, BIS, BIS-TMD and TMD) with the design parameters of the TMD subsystem optimized.

Such a new seismic protection system (BIS-TMD) is proved to be promising because the advantages of BIS and TMD can be fully used. The benefits of the new structure include effective energy dissipation (i.e. wide vibration absorption band and a stable damping effect), which results in the high performance of NPPs subject to earthquakes with various intensity levels and spectra features.

Parametric studies are performed to demonstrate the seismic robustness (e.g. consistent performance against the changing mass of the water in the gravity liquid tank and mechanical properties) which further ensures that seismic safety requirements of NPPs can be satisfied through the use of BIS-TMD.

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.

Several studies were made on paired site and soil–structure interaction (SSI) effects, but most of them were site specific. This paper aims to investigate the impact of SSI effects in conjunction with local soil condition effects on the seismic response of typical multistory low- to mid-rise–reinforced concrete (RC) buildings resting on Algerian regulatory design sites through a global explicit transfer function (TF).

A preliminary quantification of SSI effects associated with site effects is carried out through a frequency-domain solution based on the concept of rock-to-soil surface displacement TF performed for each design site category. It results from the combination of the TFs of structure, foundation and soil and reflects how seismic waves are amplified due to changes in the geological contrast between the rock and overlying soil deposits. As well, response modification factors, denoting displacement ratios of the building responses within the flexible and site-structure conditions with respect to the fixed-base one, are carried out.

In the context of Algerian seismic regulation, the study provides a clear vision of how and when site or SSI effects are expected to be influential, as opposed to the fixed-base hypothesis still retained by the current regulation. This helps engineers to be aware of the extent of the expected seismic damage.

The research applies to low- to mid-rise RC buildings within the Algerian seismic regulation, but it may also be expanded to other examples that fall under other seismic regulations.

The response modification ratio is a quantitative approach to assessing response fluctuations. It draws attention to how the roof level drift varies depending on the condition. These results can be used as numerical parameters in structural seismic design when the structure is comparable because they provide useful information about how the two phenomena interact with the structure.

The study goes beyond particular situations dealing with site specific and offers effective indicators and quantitative evaluation of combined site and SSI effects according to the current national seismic provisions, where no indication about site or SSI effects exists.

In seismic-prone areas, post-event operability is an important issue for steel warehouses. Even if surviving earthquakes with minimal probability of collapse, these structures might suffer so much damage, that their repair costs would be prohibitive. Strategies for limiting the building's damaged zones to specific parts (or “fuses”) can reduce repair costs. However, the replaceable part is limited to a small portion of the structure, whereas the rest cannot be disassembled. This is an issue for structures whose life span depends more likely on economics rather than on structural performances. Therefore, making them easily disassembled would be an advantage not only in seismic areas but also in any industrialized area. The purpose of this paper is to explore the “Design for Disassembly” (DfD) approach to complement seismic design and find a compromise between them.

In this work, one single type of structures was analysed (the moment-resisting frame), focusing on the design of a “disassemblable” seismic-resistant steel connection. The design process involved several iterations until an “optimum” compromise between seismic design and DfD was met.

This study shows that a compromise between seismic design and DfD is possible. In this case, the compromise was achieved at the expenses of more complex design calculations and a greater number of components than standard connections. However, this would be compensated for by a higher residual value for the entire structure.

Eventually, it was proved that a metric for assessing DfD steel connections is possible, but structural analyses are needed to validate it.

In recent years, three-dimensional (3D) seismic base isolation system has been studied extensively. This paper aims to propose a new 3D combined isolation bearing (3D-CIB) to mitigate the seismic response in both the horizontal and vertical directions.

The new 3D-CIB composed of laminated rubber bearing coupled with combined disk spring bearing (CDSB) was proposed. Comprehensive analysis of constitution and theoretical derivation for 3D-CIB were presented. The advantage of CDSB is that the constitution can be flexibly adjusted according to the requirements of the bearing capacity and vertical stiffness. Hence, four different combinations of CDSB were designed for the 3D-CIB and employed to isolate nuclear reactor building. A comparative study of the seismic response in terms of seismic action, acceleration floor response spectra (FRS), peak acceleration and relative displacement response was carried out.

3D-CIB can effectively reduce seismic action, FRS and peak acceleration response of the superstructure in both the horizontal and vertical directions. Overall, the horizontal isolation effectiveness of 3D-CIB was slightly influenced by vertical stiffness. The decrease in the vertical stiffness of the 3D-CIB can reduce the vertical FRS and shift the peak values to a lower frequency. The vertical peak acceleration decreased with a decrease in the vertical stiffness. The superstructure exhibited a rocking effect during the earthquake, and the decrease in the vertical stiffness may increase the rocking of the superstructure.

Although the advantage of 3D-CIB is that the vertical stiffness can be flexibly adjusted by different constitutions, the vertical stiffness should be designed by properly accounting for the balance between the isolation effectiveness and displacement response. This study of isolation effectiveness can provide the technical basis for the application of 3D-CIB into real engineering of nuclear power plants.