Resilient Design Research Articles

Performance of a seismic-resilient precast segmental column with UHPC segments and CFRP tendon

Precast segmental column has attracted a lot of research interests in recent years due to its numerous advantages. This study proposed a new seismic resilient precast segmental column with damage controllable and repairable designs. The special designs limited the damages of the column within a pre-determined plastic hinge region while keeping the other parts of the column damage-free. Also, internal energy dissipation (ED) bars were made to be replaceable so as to achieve quick post-earthquake retrofitting. UHPC was used in the damage-free parts to prevent these parts from damage. In addition, to address the potential corrosion problem of the unbonded steel tendons, CFRP tendons were used instead of steel tendons. One precast segmental column with traditional designs was also tested as a reference. Based on the cyclic test, it was found that the proposed new specimen had comparable performance to the reference column. The damages of the proposed column were limited in the pre-determined plastic hinge region. After replacing the ED bars and casting the concrete in the plastic hinge region, the seismic resilient column was tested again and it showed satisfying seismic performance. The test results demonstrated that the proposed seismic resilient designs in this study were feasible and could be used in earthquake-prone regions to keep the precast segmental column functionally restorable even after strong earthquakes.

Seismic resilient design of rocking tall bridge piers using inerter-based systems

Seismic resilient design of tall bridge piers with rocking foundation by using inerter-based systems is investigated in this work. A simplified model is developed in OpenSees to simulate the rocking bridge pier equipped with a tuned viscous mass damper (TVMD) system, wherein nonlinearity of the pier response is incorporated through a distributed-plasticity fiber-based section approach; the rocking behavior is simulated through elastic-no-tension spring elements located at the foundation interface of the pier as per FEMA 356 recommendations; an equivalent model comprising a rotational mass linked with the two terminals of the TVMD through appropriate constraint conditions is utilized for modeling the inerter-based system. Optimal design parameters of the TVMD are determined through an extensive parametric analysis, aiming to minimize the tilt angle of the bridge pier. The effectiveness of the selected design parameters of the TVMD on the seismic mitigation performance of rocking tall piers is then investigated numerically. Besides, guidelines are proposed for the design of TVMD parameters in engineering practice based on these analytical results. Nonlinear time-history analysis is conducted under both far-field and near-fault motions, followed by seismic fragility analysis for the overturning damage state, assuming the peak ground acceleration as intensity measure and the dimensionless tilt angle as the engineering demand parameter. The parametric analysis results show that the TVMD is less efficient for near-fault motions, due to reduced energy dissipation capacity caused by pulse-type feature. Additionally, the optimal parameters obtained from parametric analysis could be generalized to a higher number of seismic excitations, achieving a similar seismic performance, which indicates robustness of the TVMD. The TVMD is found able to reduce the tilt angle at the rocking interface especially during strong earthquake events, consequently increasing the overturning stability of rocking foundations adopted for tall bridge piers.

Aspects of Design in Low Voltage Resilient Grids—Focus on Battery Sizing and U Level Control with P Regulation in Microgrids of Energy Communities

Energy communities and their resiliency are both relatively new subjects of interest that need deeper analysis. The concepts are emerging in the current trend of energy decarbonization, combined with unpredictable external factors, such as extreme weather, or nearby conflicts, such as wars. To be resilient against electrical network supply outages or heavy blackouts, energy communities need appropriate design of their electrical microgrids to maintain an acceptable level of activity in both normal and critical situations. The paper deals with aspects of the design of the electrical network used by energy communities, seen as microgrids designed to offer an acceptable level of safe operation and energy resilience. While electrical network resilience covers both the public network (main grid) and local microgrid of an energy community, the paper focuses on the safe operation and resilience related to the local microgrid as a distinct goal from the one of preserving the main grid’s functionality. The first section considers definitions of energy resilience and some of the existing preoccupations on the subject. A second section of the paper presents different aspects of the design of a microgrid, with the purpose of increasing its safety in operation and energy community resilience. The section addresses electrical network architectures, multiple roles of storage resources related to prosumers and to islanded microgrids with high-RES penetration, and other aspects such as the impact of electrification of heating through, e.g., heat pumps. The next sections present selected use cases, which develop some of these design aspects by using typical real data for the analysis and assessing solutions to address resilient microgrid challenges. The selected use cases consider simplified approaches for real-time and short-term storage needs and operational use in microgrids, maintaining voltage levels in a high-RES scenario by using battery P control, and optimization of storage resources to cope with the needs. Conclusions are given in a final section, which also presents future work for a presumed continuation with other use cases related to storage means, safe operation, and resilient design of energy communities microgrids.

Application of "Behind the Barriers" Model at Neighbourhood Scale to Improve Water Management under Multi-Risks Scenarios: A Case Study in Lyon, France.

In modern urban areas, water management highly depends on the socio-ecological urban water cycle (UWC) that heavily relies on water infrastructures. However, increasing water-related hazards, natural and/or human-based, makes it difficult to balance water resources in the socio-ecological UWC. In the last decade, urban infrastructure resilience has rapidly become a popular topic in disaster risk management and inspired many studies and operational approaches. Among these theories and methods, the "Behind the Barriers" model (BB model), developed by Barroca and Serre in 2013, is considered a theory that allows effective and comprehensive analysis of urban infrastructure resilience through cognitive, functional, correlative, and organisational dimensions. Moreover, this analysis can be a reference to develop actions that improve infrastructure resilience under critical scenarios. Therefore, this study aims to study resilience design actions based on the BB model to achieve socio-ecological water balance and assess the performance of these actions. The study focuses on water management on a neighbourhood scale, which is considered the essential urban unit to study and improve the resilience of critical infrastructures, such as water services. The Part-Dieu neighbourhood in Lyon, France is selected as a case study, and it highlights the need to develop indicators to assess the performance of implemented actions in a structural and global resilience framework, to understand urban systems as complex and dynamic systems to provide decision support, and to strengthen crisis prevention and management perspectives in a dynamic approach.

Seismic performance of buildings with novel self‐centering base isolation system for earthquake resilience

AbstractThis study presents a novel self‐centering (SC) base isolation system enabled by traditional lead rubber bearing (LRB) incorporating superelastic shape memory alloy (SMA) U‐shaped dampers (hereinafter referred to as SMA‐LRB). This system is particularly suitable for some important structures (e.g., hospital buildings) that require high seismic performance and rapid recovery of normal serviceability after a severe earthquake. The working mechanism of the SMA‐LRBs is first illustrated, followed by a comparative experimental study on the traditional LRB and the emerging SMA‐LRB. Test results confirm the satisfactory flag‐shaped hysteresis loops of SMA‐LRB associated with significantly reduced residual deformation under cyclic loading. Subsequently, a refined numerical modeling strategy for these bearings is developed. The seismic performances of the SMA‐LRBs are examined systematically through two comparative reinforced concrete (RC) frame buildings, namely, the traditionally isolated and the SC isolated cases under far‐ and near‐field earthquakes. Seismic fragility analyses are further carried out through incremental dynamic analysis (IDA). The seismic responses demonstrate that the SC isolated building can match or improve the behavior of the traditional isolated buildings. Compared with the considerable residual deformation of the traditional isolated system under some earthquake events, the SC isolated system exhibits negligible residual deformation that can significantly avoid normal serviceability disruption while achieving the high‐performance objectives. The SC base isolation system can provide a promising type of advanced seismic protection device for earthquake resilient design.

Statistical analysis of climate measurements for resilient design in social housing

Climate change is a progressive phenomenon that, although it can be mitigated, it cannot be stopped. As a consequence, the level of uncertainty is high to propose resilient design strategies to counteract its effects on people's comfort and health. Likewise, a limitation is the collection of information and access to climatic data of each place, so in the present work a cycle of temperature, relative humidity and wind speed measurements was proposed in a case study of social housing in the city of Tunja, Colombia. Thus, the objective of the article is to analyze and validate the reliability of the data collected on site. For this purpose, a descriptive statistical analysis of the information was carried out with tools such as Excel and PSPP version 1.4.1. As a result, it was found that, although the average level of reliability is acceptable, there are data below the minimum value of acceptability. It was concluded that descriptive statistics allows to know the margin of error to which the data are exposed and therefore reduce the uncertainty in the resilient design

Future-robust evolution of product portfolios: Need for action from theory and practice

The evolution of products is driven by changes in the economic and technical environments through cycles of varying speed. But companies must not consider each product in isolation, but as a part of their product portfolio to reflect cross-product dependencies and interactions, as they are highly interconnected. As a result of these changes, companies face manifold challenges in the future-robust evolution of their product portfolios in a disruptive environment. A volatile environment requires the overarching and resilient design of products and related production systems. This article addresses the research question: What are the theoretical challenges and need for action in the evolution of product portfolios? How do they compare to the articulated challenges and need for action from practice? We conduct a systematic literature review to identify the challenges from a theoretical perspective and compare the results with the insights of an interview study. Overall, a need of action for the development of methods, processes and models to support the evolution of resilient product portfolios emerges. Based on the identified research gaps and the concrete challenge fields, a systematic for future-robust product portfolio development will be developed in the following work.

Resilience-oriented design for complex MEP systems in BIM

Normal operation of a Mechanical, Electrical, and Plumbing (MEP) system under random and intentional attacks is important to a building. A systematic research framework is proposed to analyze the resilience of an MEP system and optimize its design. The resilience magnitude in this research measures the ability of the MEP system to keep standard operation when component failures appear. First, the MEP model in Building Information Modelling (BIM) environment is extracted to a graph database by using Revit API, which represents the complex network of an MEP system. Second, the importance of the components and the resilience of the MEP system is analyzed based on the network theory and topological metrics. Third, the failure simulation is carried out by attacking the node of the system randomly and intentionally. Finally, the genetic algorithm is used to optimize the design of the MEP system by adding new edges. The results show that: (i) the graph database is a good representation of the MEP system, and it can convert the 3D model to a format that can be analyzed by data analysis measures, (ii) the same component in the MEP system could have different importance from different perspectives, (iii) the proposed network is more resilient with bridge ratio index and average path length improved by 6.16% and 40.58%, respectively, and (iv) the proposed intentional attack strategy is more conform to reality, and it can cause more severe results to a system. The research can contribute to the implementation of the resilience design theory in the MEP discipline, and create a bond between the 3D model and data analysis.

Economic optimization for dynamic cross-sector resilience design of energy and mobility via EVs: An emergency analysis

Electric vehicles (EVs) will play an essential role in smart cities to realize transportation electrification and power system reform for carbon neutralization. Meanwhile, the EV transportation service as mobility is incompatible with the EV storage management as real-time power supply stabilization. To realize the emerging ancillary services and the system resilience in interdependent energy/mobility systems, this paper presents an economic optimization of a dynamic energy/mobility allocation problem via EVs. We also evaluate the economic resilience performance after the occurrence of an emergent event by disconnecting part of the power lines is severed through a simulation imitating the central Tokyo area.

Fault-tolerant and resilient design of potentially dangerous systems

Increasing customer expectations, global competition and sustainability considerations have led to more and more complex technical systems. The performance, efficiency and quality are increasing, but also the possibility for faults. Designers need to develop technical systems, which will not fail as a consequence of these faults but will be resilient, i.e. they are capable to behave in an acceptable manner in the presence of faults. In recent years, strategies, methods and tools were proposed which may assist designers in this endeavor, both in the field of systematic fault-tolerant design and in the field of resilience engineering. Similar goals are pursued by strategies, methods and tools which aim to increase the safety and reliability of technical systems; these are even formulated in several international standards. This paper proposes a sensible structure to combine and integrate these strategies, methods and tools and is explaining this structure and concrete design aspects based on the development of three potentially dangerous systems - a lifting mast for an agricultural tractor, a power lift for an agricultural vehicle and a log splitting device.

Resilient Design of Continuous-time Distributed Optimization Algorithm in the Presence of Cyber-attacks

This paper presents a continuous-time resilient distributed optimization algorithm based on competitive interaction design method on connected graphs in the presence of adversaries. The competitive interaction method allows us to design a network that protects the multi-agent systems from adversaries without requiring high network connectivity. In addition, the proposed algorithm does not require the global information about the number of adversaries. First, we show that the proposed distributed algorithm solves the resilient distributed optimization problem with no attack on the communication links. Second, we show that the proposed continuous-time distributed optimization algorithm on connected graphs converges to the small neighborhood of the optimal solution in the presence of cyber-attacks onto the communication channel. Simulations are presented to illustrate our theoretical results.

Climate Change: Resilient Design Strategies for High Rainfall Areas of Southeastern Nigeria

Climate Change: Resilient Design Strategies for High Rainfall Areas of Southeastern Nigeria

Exploring Environmental Restoration and Psychological Healing from Perspective of Resilience: A Case Study of Xinglin Bay Landscape Belt in Xiamen, China

We explored the relationship between environmental restoration and psychological healing and the ecological optimization and healing function of the waterfront landscape from the perspective of resilience in the Xinglin Bay landscape belt of Jimei District, Xiamen City, China through qualitative research, in-depth interviews, and field investigations. 63 interviewees were invited from October 12 to 16, 2022 to collect data on their activity and psychological feelings in the area. The results showed that gender and frequency of activities were important variables affecting the effectiveness of landscape healing. Hydrophilic items in the Xinglin Bay landscape adopt the theme of resilience to promote the interaction between people and the environment, thereby subtly changing the cognition of visitors. The results of this study prove the relationship between resilient landscapes and physical and mental healing, highlighting the importance of the resilient design of waterfront landscapes in the urban environment and social development.

Implication of bridge resilience design and lessons from negative examples

AbstractBridge resilience is a newly proposed bridge design criterion that involves robustness, redundancy and reparability targeting on the rapidity of functionality restoration after suffering extreme actions and long-term durability deterioration. It stipulates a lower probability of reaching the ultimate limit state or strength limit state, which have been only partly involved in bridge design codes around the world. In AASHTO LRFD Bridge Design Specifications and Eurocodes, there are some design principles related to bridge resilience. Yet, it is also necessary to give more requirements for structural ductility and collapse resistance when the actual load exceeds the load combination in the code. This paper focuses on the resilience-based principles for bridge design, and exposes some problematic bridge structural systems and details, such as bridges most likely to overturning, steel bridges with fracture critical members, arch bridges with suspended desk, Morandi cable-stayed bridges, poor details for seismic vulnerability, etc. Whereas overturning is one of the worst anti-resilience scenarios, the resilience design against bridge overturning is highlighted through a detailed discussion including the calculation methods of anti-overturning factor, overturning stability of curved bridges, reasonable disposition of supports, and anti-overturning countermeasures.

Key Drivers in Using Low Damage Seismic Designs in Christchurch Buildings

Following the extensive damage to Christchurch’s infrastructure in the 2010 and 2011 Canterbury earthquakes, a complete rebuild of the city centre has been undertaken, with a particular focus on seismic-resilient buildings. This paper explores the application of different seismic-resilient technologies to buildings in Christchurch, by interviewing the structural engineers responsible for the design of six case study structures. Focus is given to the structural performance and benefits of each technology, and the key factors driving the clients’ and engineers’ decision to use the system. Comparisons are then made between resilient technologies, looking at the relative construction times and cost, areas of difficulty in design and construction, and the expected performance. Assessments are made of the knowledgeability of stakeholders, including clients and engineers, in resilient design, and the aspects that need to be addressed in the ongoing research and development of new and existing resilient technologies. Results show that the main factors identified driving clients’ and engineers’ decisions to use a seismic-resilient design were the structural performance, ease of construction and publicity. Key issues that need to be addressed during the development of new resilient systems are the durability, constructability and cost of a design, in addition to the production of design and construction aids, to both support engineers and contractors in the process, and encourage them to undertake a seismic-resilient design. Ideas are presented for increasing client and public awareness of different resilient systems available so that the demand and commission for seismic-resilient buildings in the city may increase.

Enhancing the Seismic Resilience of Steel Moment Resisting Frame with a New Precast Self-Centering Rocking Shear Wall System

In this paper, a new precast self-centering rocking shear wall system (PSCRSW) mainly composed of precast reinforced concrete (RC) wall, V-shaped steel brace and pre-pressed disc spring friction damper (PDSFD) are proposed to enhance the seismic resilience of steel moment resisting frame (SMRF). The mechanical behavior of PDSFD was investigated and simulated. The skeleton model of PSCRSW was theoretically derived and numerically validated, and the hysteretic performance under different design parameters was discussed and compared with that of the conventional RC shear wall. Based on the analyses, design principles and suggestions for PSCRSW were given. Then, an efficient seismic resilient design method for enhancement of SMRF was proposed, which considers performance objectives of multiple seismic hazard levels and has less design iteration. A typical SMRF was adopted as the prototype to be enhanced by the presented PSCRSW and design method. Reliable numerical models for the prototype and the enhanced SMRF were established, and nonlinear dynamic analyses were performed to assess the effectiveness of enhancing strategy. The results show that PSCRSW can realize approximate yielding behavior, displacement capacity and lateral strength to the conventional shear wall and can significantly lower the residual drift and wall damage. During the design, the ratio of preload to friction force for PSCRSW was suggested to be 1.5~2.0, and the bearing capacity for the wall was suggested to be amplified 1.2 times. Thereby, desirable bearing and self-centering performances can be guaranteed. The presented design method is capable of achieving the inter-story drift ratio targets and the expected roof drift ratios simultaneously, and the seismic resilience of the chosen SMRF was significantly improved by a large margin of reduction in residual inter-story drift and frame member damages.

Resilient seismic design of reinforced concrete framed buildings with metallic fuses including soil-structure interaction effects

In this paper, the authors propose and validate a code-oriented, resilient design methodology for reinforced concrete buildings with intermediate moment frames (RC-IMFs) and hysteretic energy dissipation devices (HEDDs) mounted in chevron steel bracing design as structural fuses, considering soil-structure effects. The design methodology is based on global lateral stiffness balances among different structural components (frames, bracings and HEDDs). Global seismic design parameters were specifically assessed for such stiffness ratios through extensive parametric studies for the subject structural system under study. In order to achieve an immediate occupancy seismic performance, the design sequence using capacity-design principles is clearly established and emphasized for the design of main structural elements. Soil-structure interaction (SSI) effects are included in the formal design process following the recommendations available in the seismic code for Mexico City. In order to fully test the efficacy of the proposed design methodology under a demanding seismic scenario, three buildings of 8, 15 and 24 stories were designed in soft soil sites of Mexico City close to resonant responses. Different types or HEDDs were considered and evaluated. Pushover analyses were performed in order to verify that subject buildings may achieve the objective resilient deformation mechanism (immediate occupancy) at the maximum useful ductility capacity assumed for the HEDDs. Nonlinear dynamic analyses were performed for the complete 3D designs according to the code under the action of eight pairs of acceleration records, representative of the site where the buildings were located. This was done in order to assess maximum inelastic demands, residual drifts, and fully verify and validate the proposed resilient, structural fuse code-oriented design. From the obtained results, it is confirmed that a resilient structural performance is feasible for RC-IMFs with HEDDs under the proposed code-oriented design methodology.

System resilience distribution identification and analysis based on performance processes after disruptions.

Resilience is a system's ability to withstand a disruption and return to a normal state quickly. It is a random variable due to the randomness of both the disruption and resilience behavior of a system. The distribution characteristics of resilience are the basis for resilience design and analysis, such as test sample size determination and assessment model selection. In this paper, we propose a systematic resilience distribution identification and analysis (RDIA) method based on a system's performance processes after disruptions. Typical performance degradation/recovery processes have linear, exponential, and trigonometric functions, and they have three key parameters: the maximum performance degradation, the degradation duration, and the recovery duration. Using the Monte Carlo method, these three key parameters are first sampled according to their corresponding probability density functions. Combining the sample results with the given performance function type, the system performance curves after disruptions can be obtained. Then the sample resilience is computed using a deterministic resilience measure and the resilience distribution can be determined through candidate distribution identification, parameter estimation, and a goodness-of-fit test. Finally, we apply our RDIA method to systems with typical performance processes, and both the orthogonal experiment method and the control variable method are used to investigate the resilience distribution laws. The results show that the resilience of these systems follows the Weibull distribution. An end-to-end communication system is also used to explain how to apply this method with simulation or test data in practice.

Mangrove forests as a nature-based solution for coastal flood protection: Biophysical and ecological considerations

Nature-based coastal protection is increasingly recognised as a potentially sustainable and cost-effective solution to reduce coastal flood risk. It uses coastal ecosystems such as mangrove forests to create resilient designs for coastal flood protection. However, to use mangroves effectively as a nature-based measure for flood risk reduction, we must understand the biophysical processes that govern risk reduction capacity through mangrove ecosystem size and structure. In this perspective, we evaluate the current state of knowledge on local physical drivers and ecological processes that determine mangrove functioning as part of a nature-based flood defence. We show that the forest properties that comprise coastal flood protection are well-known, but models cannot yet pinpoint how spatial heterogeneity of the forest structure affects the capacity for wave or surge attenuation. Overall, there is relatively good understanding of the ecological processes that drive forest structure and size, but there is a lack of knowledge on how daily bed-level dynamics link to long-term biogeomorphic forest dynamics, and on the role of combined stressors influencing forest retreat. Integrating simulation models of forest structure under changing physical (e.g. due to sea-level change) and ecological drivers with hydrodynamic attenuation models will allow for better projections of long-term natural coastal protection.

Evaluation of safe-to-fail flood solution alternatives and integration of safe-to-fail concept in AEC education to develop resilient coastal cities

Purpose Safe-to-fail (SF) is an emerging resilient design approach that has the potential to minimize the severity of flood damages. The purpose of this study is to explore the SF design strategies to reduce flood disaster damages in US coastal cities. Therefore, this study addresses two research questions: identifying the most suitable SF criteria and flood solution alternatives for coastal cities from industry professionals’ perspective; and investigating the controlling factors that influence the AEC students’ interest to learn about SF concepts through the curricula. Design/methodology/approach This study used the analytical hierarchy process to evaluate the SF criteria and flood solutions where data were collected through surveying 29 Department of Transportation professionals from different states. In addition, the study adopted a quantitative methodology by surveying 55 versed participants who reside in a coastal area and have coastal flood experiences. The data analysis included ordinal probit regression and descriptive analysis. Findings The results suggest that robustness is the highest weighted criterion for implementing SF design in coastal cities. The results demonstrated that ecosystem restoration is the highest-ranked SF flood solution followed by green infrastructure. Moreover, the results highlighted that age, duration spent in the program and prior knowledge of SF are significantly related to AEC students’ interest to learn this concept. Originality/value SF design anticipates failures while designing infrastructures thus minimizing failure consequences due to flood disasters. The findings can facilitate the implementation of the SF design concept during the construction of new infrastructures in coastal cities as well as educate the future workforces to contribute to developing resilient built environments.