Search

Interdependent infrastructure systems play a critical role in the normal operation and postdisaster emergency response in modern cities. However, they are vulnerable to earthquakes throughout their service life, resulting in substantial economic losses and public safety concerns. The threat posed by earthquakes underscores the necessity of implementing risk mitigation strategies. In this paper, an emergency resilience-driven decision model is proposed to address the optimization problem of seismic retrofitting of infrastructure systems. Two types of interdependencies are introduced to reflect the interaction within the infrastructure systems. Then, a resilience metric based on weighted emergency connectivity efficiency is defined to evaluate the ability of a community to provide emergency services under earthquake risks. In addition, a mathematical model and its solution algorithm are developed to maximize emergency resilience benefits while minimizing retrofitting costs, considering resource and probabilistic performance constraints during the emergency response phase. To demonstrate the applicability of the decision model, a case study is conducted on the Centerville community under seismic hazard. The results demonstrate the effectiveness of the decision model in evaluating community emergency resilience and identifying retrofit strategies that align with both resilience benefits and cost optimization criteria. Additionally, the sensitivity analysis results indicate that the intensity of interdependency may significantly affect the optimal seismic retrofit strategies and associated resilience benefits. [ABSTRACT FROM AUTHOR]

Worldwide, office buildings account for almost one-third of global energy consumption. Therefore, the energy retrofit design of office buildings could reduce total energy consumption. Considering the benefits of advanced facade systems, retrofit facade design is an effective strategy for energy conservation while improving daylight performance, occupant well-being, and productivity. This paper compares the daylight and energy performance of single and double-skin facade systems used in a typical office building in a hot climate with different space layouts. The main objective is to optimize the daylight and energy performance of various facade systems in combination with a wide range of design variables. Simulations were conducted in DesignBuilder software using a multi-objective optimization approach. Eleven design variables and 103 simulations were considered with the objective of enhancing daylight performance while reducing cooling and lighting loads. Based on the results, single-skin facade configurations could enhance daylight performance significantly compared to double-skin facades, while double-skin facades performed better by reducing the risk of glare and annual energy consumption. Using single and double-skin facade systems could reduce annual total energy consumption by 50% and 60% compared to the existing building. [ABSTRACT FROM AUTHOR]

This research delves into the intricate realm of social housing flat units within tower blocks in Leicester, as a microcosm that serves as a perfect reflection of the larger problem of fuel poverty among social housing systems within the UK. The multifaceted approach intertwines energy efficiency upgrades, indoor comfort, and resident satisfaction. Rooted in a comprehensive methodology, this research seeks to address pressing societal challenges within these architectural projects, from fuel poverty and well-being to environmental sustainability and social justice. Through surveys, interviews, audits, simulations, and detailed analyses of summer and winter thermal performance, this study navigates the complex interplay of factors that influence retrofit success. The findings underscore the transformative potential of comprehensive retrofit measures and the paramount importance of resident engagement while offering a potential holistic checklist for future projects. This research paves the way for future studies encompassing contextual diversity, interdisciplinary collaboration, and long-term impact assessment. As it advances, these findings guide the commitment to fostering positive change, enhancing lives, and contributing to a more sustainable and equitable future in social housing retrofit endeavours. [ABSTRACT FROM AUTHOR]

Energy demand is rapid increase with the increase in usage of energy-consuming devices and growth in global buildings floor area. For this reason, many countries have developed policies and rating systems for converting current buildings to more energy-efficient and sustainable ones. However, religious buildings such as mosques were given little attention. Mosques are considered one of the unique building types for their operational scheme, and occupancy pattern throughout the year differ from any other types of buildings. Many factors affect mosques’ operational performance, such as energy wastage from their intermittent operation, poor building envelope characteristics, excessive lighting and HVAC systems, and poor thermal and visual comfort for the occupants. This paper presents a framework that aids in assessing and enhancing the operational performance of mosque buildings using five main evaluation criteria. The development of the framework involves four main stages. The first stage involves data acquisition using 3D laser scanning for electronic building documentation and site investigation that identifies the main factors affecting mosques’ operational performance. The second stage involves constructing the BIM model for developing the energy analysis model using IESVE (Integrated Environmental Solutions-Virtual Environment) software. Then, the third stage considers proposing different retrofit strategies that could be applied to evaluate their impact on the mosques’ operational performance. Finally, the last stage identifies the assessment criteria for evaluating the impact of the proposed retrofit strategies and developing a decision-making model using the Analytical Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as decision-making techniques. The framework is demonstrated using an actual case study of Imam Al-Hussein Mosque in Cairo, Egypt, to demonstrate its main features.

Each of the total Life-Cycle Cost (LCC) and resilience index are valuable indicators of infrastructure management against hazard events during its service lifetime. In this study, the proposed multi-objective framework provides a systematic methodology for decision-makers to select the optimal retrofit strategies that minimize the LCC while satisfying a given level of resilience, for which various retrofit strategies are chosen. For each case, the fragility curves are established through IDA for calculating the resilience and LCC, which incorporates the effects of complete or incomplete repair actions of damage conditions induced by multiple occurrences of previous hazard events. This study employs a well-known 'NSGA II' to identify the optimal set of solutions. The various aspects of the optimal retrofit strategies are thoroughly investigated and discussed for an actual structure in the refinery sites as a case study infrastructure. [ABSTRACT FROM AUTHOR]

A growing body of research shows that retrofitting practices can potentially reduce energy demand in hospital buildings and enhance indoor air quality. Yet, there is a lack of comprehensive reviews associated with green retrofitting practices in hospital buildings. This study aimed to undertake a systematic review of the past literature on retrofitting techniques used to improve indoor air quality and energy efficiency in hospital buildings, to identify barriers to its uptake, and to recommend solutions to identified challenges. For this reason, a systematic review was conducted for the published research from various academic databases. Findings showed a growing uptake of various retrofitting strategies for indoor air quality in hospital buildings. As a result, hospital management or building owners might consider addressing these challenges to facilitate the uptake and implementation of retrofitting practices in their facilities. [ABSTRACT FROM AUTHOR]

This research delves into the intricate realm of social housing flat units within tower blocks in Leicester, as a microcosm that serves as a perfect reflection of the larger problem of fuel poverty among social housing systems within the UK. The multifaceted approach intertwines energy efficiency upgrades, indoor comfort, and resident satisfaction. Rooted in a comprehensive methodology, this research seeks to address pressing societal challenges within these architectural projects, from fuel poverty and well-being to environmental sustainability and social justice. Through surveys, interviews, audits, simulations, and detailed analyses of summer and winter thermal performance, this study navigates the complex interplay of factors that influence retrofit success. The findings underscore the transformative potential of comprehensive retrofit measures and the paramount importance of resident engagement while offering a potential holistic checklist for future projects. This research paves the way for future studies encompassing contextual diversity, interdisciplinary collaboration, and long-term impact assessment. As it advances, these findings guide the commitment to fostering positive change, enhancing lives, and contributing to a more sustainable and equitable future in social housing retrofit endeavours.

The existing building stock is crucial for enhancing decarbonization targets and mitigating climate change. This article delves into a methodological approach that combines prospective life cycle assessment, building thermal simulation using projected future climate data, and global sensitivity analysis to pinpoint the most influential parameters under current climate conditions and future scenarios. The methodology covers plausible decarbonization pathways for the electricity mix, considering the growing utilization of renewable sources, which are influenced by the building locations. An adaptive reuse process involves converting a historic residence into an office building to validate the proposed methodology. Several retrofit strategies are assessed, such as exterior wall insulation, roof insulation, and window replacement. The findings reveal a 12% rise in average usage impacts and a 7% increase in cradle-to-use impacts from the base scenario to future climate projections. Embodied impacts surpass use-phase impacts by 23% in future climates and 33% in certain baseline scenarios. Utilizing future climate data in the life cycle analysis to estimate energy requirements can aid in forecasting building performance under climate change, especially in adapting the existing building stock for enhanced thermal comfort with minimal environmental impact. [Display omitted] • Existing buildings adaptation with low environmental impact under future climate. • The wall U-value is the most influential parameter regardless of climate scenario. • Roof and window parameters become less influential in future climate scenarios. • Embodied impacts exceed operational impacts in 33% of the retrofit alternatives. • The embodied phase becomes even more impactful with the grid decarbonization. [ABSTRACT FROM AUTHOR]

The improvement of the seismic performance of existing buildings is majorly accomplished by adopting one or more retrofitting interventions. The selection of the latter is generally made considering conventional parameters, based on e.g. economic or structural considerations, without carrying out a comprehensive and integrated comparison of different retrofitting solutions. Instead, for an optimal choice of a retrofitting option, it is necessary to include different evaluation criteria to better assess the effectiveness of each strategy. This aspect becomes even more relevant when referring to buildings of strategic importance, such as school buildings, for which typical structural response-oriented criteria may not be enough to identify the best choice. This paper implements and scrutinizes various multi-criteria evaluation methodologies to comparatively assess retrofitting options for an existing reinforced concrete (RC) school building, considering different aspects, weighted according to their deemed importance. These evaluation criteria focus not only on the structural performance but also on how each intervention affects the operability of the building and on economic aspects. A comparative performance assessment is conducted on a detailed numerical model, able to reproduce the main structural deficiencies observed during past earthquakes in RC school buildings. Then, different retrofitting interventions are identified with the aim to solve the structural issues and improve the overall performance of the case-study school building. The seismic performance is quantified in terms of seismic losses, including the contribution of non-structural elements, amongst several other metrics. Finally, the outcomes of the different evaluation methodologies, which denote a non-unanimous optimal solution, are compared and critically analyzed. [ABSTRACT FROM AUTHOR]

Regeneration of existing buildings and abandoned areas is a governmental and European key objective. This research focuses on Poveglia: an abandoned island in the Venetian lagoon, Italy. The underpinning idea concerns the upgrade of Poveglia to a zero energy Cognitive University Campus, connected to other educational institutions in the lagoon. The vision aims at reusing abandoned islands combining architecture, learning environments and digital networks, to demonstrate the potential of new technologies for the transformation of abandoned areas. The case study demonstrates the effectiveness of employing improved and revised systems and tools, developed in eLUX lab at the University of Brescia, for the regeneration of the island. The inclusion of the island in a smart campus network results in triggering positive synergies both enhancing energy efficiency and the learning environment. A further development concerns the setup of strategies for historical preservation, energy efficiency and renewable energy production.

Recent hurricanes indicated that retrofitted residential buildings are still susceptible to wind- and flood-induced damage in coastal areas. This poor performance indicates that flood retrofit methods need to be evaluated in terms of efficiency and effectiveness to resist hurricane wind and flood loads. This paper discusses various aspects in the hurricane-resistant design and retrofit of coastal residential buildings, including potential wind and flood-induced damage, risk mitigation, cost of retrofit methods, and the need for better standards. The cost analysis is performed for a typical one-story wood-frame residential building with a gable roof system considering several flood retrofit methods. The result indicates that selecting a flood protection level higher than the basic 100-year flood level can significantly decrease the risk of damage. This result seems appropriate and essential for specific hurricane-prone regions considering recent changes in the intensity/frequency of storms. A review of actual damage types indicates that wood-frame elevated houses are susceptible to experiencing wind-induced damage to the structural system and more extensive damage to the envelope system. The performance of breakaway walls below the base flood elevation (BFE) strongly depends on the connections between such walls and structural members. The result of cost analysis indicates that the foundation type can directly affect the total cost of retrofit solutions, such as elevation, wet, and dry methods for houses in coastal areas. Regarding the elevation method, adding a freeboard higher than the BFE does not significantly increase the total cost once the elevation method is selected as the preferred retrofit solution. [ABSTRACT FROM AUTHOR]

Low to severe earthquakes occur around the world every year, damaging and causing structural failure in buildings. Consequently, seismic improvements are required for existing buildings that are vulnerable to damage by seismic forces. The objective of this study was to investigate retrofitting strategies in terms of their sustainability. Mandalay, Myanmar, was selected as the study area as it is located near the Sagaing fault, which itself is in a strong earthquake zone (seismic zone 4). A three-storied RC building with a non-seismic design was selected as a case study building. An investigation was carried out into the performance and vulnerability of the building under three earthquake hazard levels. The vulnerability index value was calculated using the Priority Index method. Meanwhile, non-linear static pushover analysis was performed to investigate the performance of the existing building using SAP2000 V14 software. Four different types of retrofitting strategies were considered, namely reinforced concrete shear walls with openings, reinforced concrete shear walls without openings, steel plate shear walls, and finally steel bracing. Among these, it was found that the use of steel plate shear walls was the best retrofitting technique, owing to it having the best performance along with the lowest displacement. Its performance level reached up to the Immediate Occupancy (IO) level even under the conditions of a Maximum Consider Earthquake (MCE).

Although the study of roofing systems (from coverings to structure of the roof) is of great significance to energy efficiency and sustainable development, design and construction of new roofs on top of existing roofs in buildings has not received sufficient attention. This study discusses re-roofing as one of the key options to reduce energy consumption and improve overall building performance. The more conventional choice and more frequently chosen option for building energy retrofit is vertical building envelope components, however, this paper presents the case study of a proposed retrofitting concept for the roof of an existing building. Using a simulation methodology, the research demonstrates how the proposed retrofitting concept improves the energy performance using electricity generated and external conduction gain as evaluation metrics. The proposed novel re-roofing concept consists of thermal insulation, waterproofing and electric energy generation properties. More specifically, the design concept includes a three-layer roofing system consisting of (from exterior toward interior): a PV panel, an EPDM membrane and an insulation layer. The main goal of this study is to develop a concept for an innovative re-roofing solution that demonstrates the feasibility of turning an old building into a watertight and energy producing system. • The study of roof systems is of great significance to energy efficiency. • BIM can be used to study cost-effectiveness analysis for roof systems. • PV panel and insulation retrofits can provide greater energy efficiency improvements. [ABSTRACT FROM AUTHOR]

How can we evaluate the cost-effectiveness of retrofit interventions aiming at reducing the seismic vulnerability of an existing building? What level of shaking intensity should the retrofitted building sustain? These are open questions affecting either the pre-earthquake prevention, the post-earthquake emergency and the reconstruction phases. The (mis)conception that the cost of retrofit interventions would increase linearly with the level of safety required in designing the intervention often discourages stakeholders to consider alternative retrofit options. As a result, a minimum (in some cases prescribed by-law) level of safety is often targeted, leading in some cases to no-action. Furthermore, the performance measure enforcing owners to take action is generally evaluated following a deterministic approach. When the assessment does not directly reflect, even in simplified terms, epistemic uncertainties and aleatory randomness, it can result in misleading confidence on the expected performance. The present study aims at contributing to the delicate decision-making process of retrofitting existing structures, by developing a framework to assist stakeholders with the evaluation of the actual improvement of the performance, expressed in terms of reduction of collapse probability, of alternative strategies of intervention as well as targeted retrofit levels. With reference to a pre-1970 case study building located in New Zealand, alternative retrofit solutions are considered, targeting different levels of performance, and the probability of reaching collapse when considering a set of ground-motions is evaluated, providing a correlation between the deterministic safety index adopted in the design phase (named "Percentage of New Building Standard" adopting New Zealand regulations) and the expected annual probability of collapse. [ABSTRACT FROM AUTHOR]

In order to raise awareness of the role of building information modeling (BIM) in improving energy efficiency and comfort conditions, the work introduces a strategy of combining building simulation tools and optimization methods. Furthermore, it emphasizes the fact that a combination of these strategies with BIM can improve not only the construction process but also enable exploration of alternative approaches. The work discusses the potential application of data integration methodology for an office environment and focuses on the review of the potential performance of integrated systems. It also explains how BIM can help facilitate review of results and methods for improving building performance in terms of energy efficiency and indoor environmental quality. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess an energy retrofit of a building representative of those in public tertiary stock, to improve energy performance toward nearly Zero-Energy Building (nZEB) requirements. The building is located in the campus of the Politecnico di Milano University (Italy). Several hypothetical improvements regarding the building envelope and plants were assessed in terms of energy savings, costs, and the reduction of greenhouse gas emissions. The results of the study show that it is possible to reduce primary energy demand and associated emissions up to 40% from the current values by adopting market-available and well-proven technological solutions for retrofit. Moreover, exploiting on-site renewable energy sources, the net energy consumption can be near zero. However, an economic analysis of the application of these technologies has highlighted many critical elements related to the implementation of some solutions. This is particularly true for actions related to the thermal insulation of the building envelope and to the installation of ventilation system with heat recovery. Since nZEB requirements are related to the concept of economic performance, this paper gives useful hints to better understand the viability of many commonly adopted actions and strategies for reaching such targets in building retrofit cases. [ABSTRACT FROM AUTHOR]

In the United States, K-12 school buildings spend more than $8 billion each year on energy--more than they spend on computers and textbooks combined [1]. Most occupied older buildings demonstrate poor operational performance--for instance, more than 30 percent of schools were built before 1960, and 53 percent of public schools need to spend money on repairs, renovations, and modernization to ensure that the schools' onsite buildings are in good overall condition. And among public schools with permanent buildings, the environmental factors in the permanent buildings have been rated as unsatisfactory or very unsatisfactory in 5 to 17 percent of them [2]. Indoor environment quality (IEQ) is one of the core issues addressed in the majority of sustainable building certification and design guidelines. Children spend a significant amount of time indoors in a school environment. And poor IEA can lead to sickness and absenteeism from school and eventually cause a decrease in student performance [3]. Different building types and their IEQ characteristics can be partly attributed to building age and construction materials. [4] Improving the energy performance of school buildings could result in the direct benefit of reduced utility costs and improving the indoor quality could improve the students' learning environment. Research also suggests that aging school facilities and inefficient equipment have a detrimental effect on academic performance that can be reversed when schools are upgraded. [5] Several studies have linked better lighting, thermal comfort, and air quality to higher test scores. [6, 7, 8] Another benefit of improving the energy efficiency of education buildings is the potential increase in market value through recognition of green building practice and labeling, such as that of a LEED or net zero energy building. In addition, because of their educational function, high-performance or energy-efficient buildings are particularly valuable for institution clients and local government. More and more high-performance buildings, net zero energy buildings, and positive energy buildings serve as living laboratories for educational purposes. Currently, educational/institutional buildings represent the largest portion of NZE (net zero energy) projects. Educational buildings comprise 36 percent of net zero buildings according to a 2014 National New Building Institute report. Of the 58 net zero energy educational buildings, 32 are used for kindergarten through grade 12 (K-12), 21 for higher education, and 5 for general education. [9] Finally, because educational buildings account for the third largest amount of building floor space in the United States, super energy-efficient educational buildings could provide other societal and economic benefits beyond the direct energy cost savings for three reasons: 1) educational buildings offer high visibility that can influence community members and the next generation of citizens, 2) success stories of the use of public funds that returns lower operating costs and healthier student learning environments provide documentation that can be used by others, and 3) this sector offers national and regional forums and associations to facilitate the transfer of best design and operational practices. [ABSTRACT FROM AUTHOR]

In the last few years, the renovation and refurbishment of existing buildings have become the main activities of the construction industry. In particular, many studies have recently focused on the mechanical and energy performances of existing retrofitted/refurbished facilities, while some research has addressed the environmental effects of such operations. The present study aims to assess the environmental impact of some retrofit interventions on an existing reinforced concrete (RC) building. Once the structural requirements have been satisfied and the environmental effects of these retrofit solutions defined, the final purpose of this study is to identify the most environmentally sustainable retrofit strategy. The environmental impact of the structural retrofit options is assessed using a life-cycle assessment (LCA). This paper sets out a systematic approach that can be adopted when choosing the best structural retrofit option in terms of sustainability performance. The final aim of the study is to also provide a tool for researchers and practitioners that reflects a deep understanding of the sustainability aspects of retrofit operations and can be used for future researches or practical activities. [ABSTRACT FROM AUTHOR]

According to directive 2010/31/EU, a NZEB (nearly zero energy building) is defined as a high performance building whose very low or almost zero energy needs should be mostly provided by renewable sources. The study reported in this work has the objective to establish criteria and design solutions to improve buildings energy performances in order to reach NZEB targets for those buildings characterized by historical constraints. For this purpose, a comparative numerical analysis on the space cooling and heating of a historical building sited in Agrigento (Sicily, Italy) was performed by means of two energy tools: Termo and Trnsys. The first one is a stationary energy certification software based on the algorithms and mathematical methods listed in the UNI TS 11300 standard reference. The second one is a well calibrated dynamic tool based on hourly climate data and able to take into account the thermal inertia phenomena of structures. In order to obtain reliable results, measured climate data extracted from a weather station located near the reference building were used as input for the simulations. Starting from the simulation results, several retrofit scenarios were hypothesized, in order to achieve NZEB target, and then followed by a cost analysis carried out to reach optimal economic solutions and energy savings. The study can constitute a contribution to policy formulation and adoption of measures to facilitate design choices for the energy improving of historical buildings. [ABSTRACT FROM AUTHOR]

This paper discusses sustainable strategies have been implemented to improve the energy performance for the housing sector in arid climate, especially villas. A practical case study along with field measurements is presented in order to highlight the behavior of the energy performance after implementing energy conservation measures in practice. The residential sector in arid climate especially in GulfCountries has a significant share of carbon emissions. Millions of householders occupy villas and town houses. The harsh hot weather of this region is one of the reasons for a high demand on the cooling energy and the electricity consumption in the housing sector. Thus, there is a real potential to retrofit the existing houses with practical energy conservation measures. These techniques are affordable and feasible economically. Also, they play a substantial role to increase the energy efficiency of the residential units on the demand side. This study discusses the results of 12 months were monitored after implementation of energy savings measures on selected 10 villas in the capital of UAE – Abu Dhabi. This research highlights different responses by each villa against the implemented energy savings opportunities. The target of these executed strategies is to improve the energy performance of these selected villas after conducting a detailed energy assessment and implementing its recommendations. A detailed analysis of the electricity performance of the baseline and the monitoring period has been performed by using the actual readings of the existing power meters according to the international performance measurement and verification protocol. This research presents the energy data for the entire year before and after the implementation of the energy conservation measures – ECMs. These ECMs show the potential of improvement of energy performance in the housing sector by increasing the energy efficiency by 25.1% in average through low and medium cost techniques. The percentage of savings varies from 14.4% to 47.6% of the total electricity according to the individual operating conditions for each villa and the behavior of occupants. As a result, they contribute reducing the carbon and GHG emissions, and open new perspectives of energy savings for housing sector in arid climates. [ABSTRACT FROM AUTHOR]

Cyprus’ building stock energy saving potential is considerably high due to the absence of legislation and regulations governing the energy performance of buildings, prior to the country's accession to the European Union. In this study, a methodology is proposed and applied to a typical residential building to assess the financial attractiveness of alternative retrofit scenarios. An advanced simulation software tool is utilised to measure the energy performance of a typical residential building in terms of envelope characteristics, construction materials and Heating, Ventilation and Air Conditioning system. The thermal model is used to assess the impact of alternative retrofitting scenarios. Then, an economic model is developed to evaluate the financial impact over the investment horizon. Finally, a risk analysis is conducted to investigate the stochastic behaviour of key input variables. [ABSTRACT FROM AUTHOR]

The unique dynamic response of skewed bridges causes them to experience more noticeable damage compared to straight bridges during seismic events. The effectiveness of different retrofit strategies on the fragility of skewed bridges can change with the skew angle. This article assesses the impact of skew angle and various retrofit strategies on the fragility of multi span continuous concrete I-girder bridges. The results indicate that the level of effectiveness of a retrofit strategy is highly dependent on the skew angle and damage state of interest and an appropriate retrofit strategy should be chosen based on the vulnerability of the components. [ABSTRACT FROM AUTHOR]

Over the past ten years, the development of analytical procedures to accurately evaluate the seismic performance of existing buildings has gathered the attention of researchers. This has resulted in the publication of several standards, which, however, inadequately cover the issue of retrofit strategy selection. In the present article, a procedure that allows a comparison of available strategies in order to select the optimum solution for an existing deficient building is proposed. The procedure is based on calculating the pushover curve for the unstrengthened structure. A capacity spectrum is then estimated assuming different retrofit scenarios, which is then used for the evaluation of the strategies. The latter is based on criteria that assess the main structural system characteristics and how each solution benefits them. The final step of the procedure introduces simplified rules that allow the approximate design of each retrofit solution, which allows the evaluation of their applicability. The proposed procedure was applied to two idealized buildings with different structural systems. Results obtained indicate that less effective or inapplicable rehabilitation strategies were properly detected. Thus, the results were considered acceptable in terms of identifying the possible optimum strategy, which, however, should be verified with a detailed design of the retrofit system. [ABSTRACT FROM AUTHOR]

• Lateral static and impact behavior of propped cantilever columns was investigated. • The effectiveness of CFRP seismic-retrofit under impact has been experimentally investigated. • A comparison of the lateral impact and static behavior of RC columns is reported. • A semi-empirical equation is proposed to estimate the dynamic response given the static behavior. • CFRP seismic-retrofit is effective in reducing damage under vehicular lateral impact loads. The effectiveness of Carbon Fiber Reinforced Polymer (CFRP) seismic-retrofit of circular Reinforced Concrete (RC) bridge piers under vehicular lateral impact loading is addressed in the present work performing experimental tests. Sixteen 1 / 3 scale RC bridge piers with circular cross-sections characterized by three different configurations of longitudinal and transverse reinforcements were tested with and without CFRP seismic-retrofit. In the first case, tested columns represent common shear-deficient RC bridge piers designed with obsolete design practice or for non-seismic areas. In the second case, CFRP wrapping is applied according to common seismic-retrofit practices to increase the shear capacity and ductility of columns. Experimental tests were carried out under static and lateral impact loading with propped cantilever conditions reproducing a typical short-span viaduct bridge pier configuration. In the static tests, the lateral load was applied monotonically through a hydraulic jacket under equivalent impact conditions. In impact tests, the lateral impact load was applied through a colliding truck equipped with a rigid hammer at the typical vehicular impact location adopting two different impact velocities (3 and 4.5 m / s). A critical investigation of the transient dynamic characteristics, damage evolution, and post-impact damage is conducted by comparing the results obtained with and without CFRP seismic-retrofit, and under static and dynamic loading conditions. It is shown that CFRP seismic-retrofitting of circular RC bridge pier can also be effective in reducing the vulnerability under lateral impact loading. The CFRP-retrofit approach adopted in this study meets the requirement of multi-hazard prevention improving the robustness of the bridge. Finally, a semi-empirical equation for predicting the maximum displacement under impact loading is derived based on experimental results. The proposed equation adopts the results of a static test as a proxy for assessing the dynamic behavior allowing for the design of the required shear and flexural load-carrying capacity. [ABSTRACT FROM AUTHOR]

This paper investigates the application of surrogate modelling to create bottom-up archetype models, to improve the energy performance of specific residential building archetypes. The objective of this study is to quantify the application range(s) of surrogate models to predict and improve the annual energy performance of single-family home archetypes. Six distinct surrogate models were developed using multivariate regression and artificial neural networks, based on 6000 simulated samples extracted from four different century home archetypes in Toronto (Canada) as a result of random field study within a target neighbourhood. The results show that a single surrogate model can predict the annual energy requirements for four distinct archetypes with 7.87% average error with a multivariate regression model and 4.13% average error using an artificial neural network in 0.00047 and 0.013 ms respectively. These results indicate that the bottom-up surrogate model can describe the relationship between retrofit strategies and annual energy demand with substantial computational time savings. The findings of this study support the future application of surrogate modelling to develop bottom-up archetype models to continue the development of the Toronto Archetype Project and to support a national retrofit strategy in Canada. [ABSTRACT FROM AUTHOR]

This research project was undertaken in the Turkish Republic of Northern Cyprus (T.R.N.C). The objective of the research is to investigate the occupants’ behaviour and role in the refurbishment activity; to explore how and why occupants decide to change building components and to understand why and how occupants consider using energy-efficient materials. The study is conducted through semi-structured interviews to identify occupants’ behaviour as it is associated with refurbishment activity. This research paper presents the results of semi-structured interviews with 70 homeowners in a selected group of 16 housing estates in four different regions of the T.R.N.C. The expected solutions should be effective, environmentally acceptable and feasible given the type of housing projects under review, with due regard for their location, the climatic conditions within which they were undertaken, the socio-economic standing of the house owners and their attitudes, local resources and legislative constraints. Furthermore, the study goes on to insist on the practical and long-term economic benefits of refurbishment under the proper conditions and why this should be fully understood by the householders. [ABSTRACT FROM AUTHOR]