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Unbonded fiber-reinforced elastomeric isolators (UFREIs) are a potentially low-cost and viable alternative for application as base isolators in low-rise buildings due to their adaptive characteristics. The behavior is denoted adaptive because the device exhibits well-defined lateral softening and subsequent substantial stiffening responses depending on the loading level. Since adaptive characteristics could have a significant effect on the seismic response of base-isolated structures, proper modeling of adaptive devices is crucial. There are several numerical modeling techniques for considering the adaptive characteristics of UFREIs. However, to date, none accurately fit the experimental hysteresis loops of UFREIs at large displacements where there is more dissipated energy due to full rollover. In this paper, an impact model is added to the leading numerical models of UFREIs (i.e., the Bouc–Wen model with a fifth-order polynomial and the algebraic model) to accurately capture the force-displacement hysteresis in lower and larger displacement amplitudes. The proposed impact model is then validated using prior experimental cyclic loading tests for square and rectangular specimens and shake table tests for different earthquake records. The effect of the impact model was also investigated through comparison with the response of the existing phenomenological models (e.g., the Bouc–Wen model with a fifth-order polynomial, the algebraic model, and the elastomeric bearing (Bouc–Wen) element). The results show that incorporating the impact model will improve the ability of the current numerical models to capture the behavior of UFREIs, particularly at larger amplitudes. [ABSTRACT FROM AUTHOR]

The wall system constitutes a large portion of the material used in building construction. Although interior walls cover more surface area within a building, published literature has mainly focused on the performance assessment of exterior walls. The aim of this research is to examine the life cycle environmental, social, and economic performance of interior wall construction methods (i.e., concrete block masonry, wood stud gypsum, and steel stud gypsum) used for industrial, commercial, and institutional buildings. The findings indicated that the environmental, social, and economic performance of concrete block masonry wall is 49%, 23%, and 18% higher than the next best alternative. This research has generated important information that can be used in material specification for greener building design. [ABSTRACT FROM AUTHOR]

Stormwater infrastructure system (SWIS) is a main component of a municipal infrastructure system that safely passes excess runoff, controls floods, and manages pollutant discharges. A comprehensive literature review has revealed that stormwater infrastructure level of service (LOS) assessment, an important step in asset management, has been abstractly defined. LOS assists in infrastructure performance assessment as well as investment decision-making. This research proposes a methodological framework for LOS assessment of SWIS and adopts the proposed method in asset management decision-making. A hierarchical framework was developed to assess the LOS by using key performance indicators. The proposed framework was demonstrated in a case study for a municipality in Southwestern ON. To improve the LOS of sub-catchments with low LOS, low-impact development (LID) controls were proposed. The cost-benefit analysis revealed that an investment of $110 950 in LIDs could increase the LOS by 26.4% (from medium to good). [ABSTRACT FROM AUTHOR]

Building information modeling (BIM) can be recognized as the most promising technology that was introduced to the construction sector in the recent past. The current BIM-based safety risk assessment methods ignore data uncertainty. Hence, this study integrates BIM with fuzzy set theory for safety risk prediction. A Fuzzy Inference System (FIS) was developed based on the causality of safety incidents. The FIS extracts construction project data from BIM models while automatically assessing each potential safety hazard and project's total risk. The proposed method was demonstrated by using a building project in which the safety risk was predicted as low. Safety records of the above project revealed that no safety incidents were recorded in this project. The proposed method can indicate the safety risks level at various stages of a construction project and help to enhance the safety of construction workers on a construction site. [ABSTRACT FROM AUTHOR]

Energy retrofits can improve the sustainability of a building by decreasing the energy consumption and resulting GHG emissions throughout its life. Adopting critical life cycle thinking is crucial when deciding on how to implement building retrofits. This article first evaluates innovative and proven building energy retrofits through a life cycle thinking lens. Next, it develops a methodological framework to assess building retrofits using four principal measures: environmental, economic, social, and technical criteria. The proposed method was demonstrated using an institutional building in Windsor, Ontario, as a case study. The case study revealed that the selected retrofit might result in the least energy savings, but it is still the preferred alternative because other factors can present valuable trade-offs that are desirable. The outcomes of this research, with the demonstrated tool, will assist building managers in determining the optimal energy retrofit for their buildings. [ABSTRACT FROM AUTHOR]

In Canada, most single-family wood-frame residential structures in seismically hazardous regions are constructed according to Part 9 of Division B of the National Building Code (or similar provincial standards) using nonengineering methods. These structures are expected to perform well during an earthquake regarding life safety but may sustain severe economic losses. Seismic isolation is an emerging technology that provides excellent life safety and economic performance. While this technology has proven effective at protecting structures from earthquakes, no nonengineering methodologies exist that are compatible with Part 9 methods. This limitation produces significant testing, design, and cost barriers that restrict the application of base isolation on vulnerable Part 9 structures. To eliminate or reduce these cost barriers, a program framework was developed to perform the engineering seismic design and analysis for a base-isolated Part 9 single-family residential structure. The proposed methodology further encourages the application of seismic isolation to Part 9 structures. [ABSTRACT FROM AUTHOR]

Construction project proposal evaluations received much attention during the recent years due to increased awareness of sustainability, value for money, and transparency. The bid evaluation matrix is the commonly used method in the construction industry for project proposal evaluation. The subjective judgments used for evaluation criteria are associated with significant uncertainty. Moreover, the transformation of qualitative evaluations raises significant data uncertainty. Attempts have been made by previous researchers to incorporate uncertainties associated with project bid evaluations, but the ability of those methods to account for "true uncertainty" is questionable. The objective of this paper is to develop a fuzzy logic-based evaluation framework for project proposal evaluation. This use of type-2 fuzzy numbers sets the proposed approach apart from the current body of knowledge. An algorithm using type-2 fuzzy numbers was developed to define input uncertainty and parameter weights. The developed method was demonstrated using a building construction project case study. The proposed approach enables quantifying qualitative evaluations more comprehensively from a scientific basis, forming a generic proposal evaluation method applicable to various industry sectors. [ABSTRACT FROM AUTHOR]

Improving the environmental performance of built environments has received wider interest in the recent past. Asset management is an under-utilized strategy to enhance and maintain desired environmental performance of a building at low life cycle costs (LCC). Current asset management decision-making methods are not fully capable of incorporating future technological changes and complex time sensitive environmental demands. There is a knowledge gap in incorporating factors such as environmental performance, risk and time sensitivity to foster dynamic asset management decision making. This paper presents a multi-period asset management method for public buildings to minimize LCC and attain climate action goals. A scenario planning approach is used to incorporate future changes in technologies, costs and organizational policies. Risk based prioritization is used to compare and select maintenance alternatives in a given period. Value at risk is used to identify the lowest risk capital planning strategy for an organization. The proposed approach was demonstrated using an operating aquatic centre building in British Columbia, Canada. Three possible future scenario were considered. Proposed method was used to develop multi-period maintenance plans for future scenarios. Based on the analysis, Great Transitions scenario is expected to achieve the least financial risk. The proposed approach enable capital asset planning by complying with changing climate action targets in a stochastic environment. [ABSTRACT FROM AUTHOR]

Climate-conscious development is a topic which has received widespread attention. One consequence of this is the prominence of greenhouse gas (GHG) emissions reduction targets set at various administrative levels (i.e. global, national, provincial and local governments). Despite the global interest, current models are incapable of integrating GHG emission reduction into the urban planning. This study presents lessons learned from a climate conscious growth study conducted for a fast-growing municipality in Okanagan, British Columbia, Canada, offering a model for local government target-setting generalizable across networks of communities, leading to significant cumulative GHG reductions at global scale. The study uses the results of engineering-based research to evaluate multiple planning scenarios developed to explore options for the subject municipality’s future urban form and the associated GHG emissions for the target year 2040. Overall municipal GHG emissions for each scenario were simulated in the study considering the residential and transportation emissions projections. The findings indicated that the lowest emissions scenario was the ultra-compact growth model without area structure plan (ASP) allocations. Accordingly, it was concluded that a densified growth strategy with a higher share of multi-unit residential development is technically the best path forward in municipal growth planning to meet climate action targets. Negative public perception of increased densification in urban areas remains an obstacle to the technically best solution. Moreover, per capita basis could be a more feasible approach for GHG emissions target setting. This study’s outcomes are expected to inform public sector institutions and decision makers in setting GHG targets and climate action planning. [ABSTRACT FROM AUTHOR]

Ongoing climate action programs are prompting more stringent energy performance standards for buildings. Consequently, energy retrofitting of existing buildings has become a common climate action initiative around the world. Building owners are keen to assess the technical and financial feasibility of energy retrofitting in pre-project planning stages. Life cycle cost analysis (LCCA) involves assessment of the economic cost of an asset or a service. LCCA, which is a data-intensive process, is heavily affected by data uncertainties; however, traditional deterministic LCCA models are oblivious to data uncertainty and this can have a significant effect on the final decision. As a solution, this paper proposes a novel LCCA approach for building energy retrofits. The proposed approach calculates life cycle cost (LCC) by adopting fuzzy set theory. In order to illustrate the proposed methodology, a case study was conducted for a public building operated in the Okanagan region of British Columbia, Canada. Two energy retrofit alternatives − a major retrofit and a deep retrofit − were compared using the proposed fuzzy set theory-based approach and the traditional deterministic LCCA approach. Even though the deterministic result had a strong membership to the fuzzy membership function of the LCC, the range of possible LCC is wide. Use of the fuzzy-based approach would enable the forecasting of possible future LCC as a result of changes in macro-economic factors. This information would allow building managers to plan for adverse future scenarios. [ABSTRACT FROM AUTHOR]

The building stock in the world consumes approximately 40% of the energy and emits one third of the total greenhouse gases emissions (GHG). Improving the energy efficiency in buildings is vital to address the climate change and achieve energy independence (i.e. to become net-zero energy). Improving energy performance in existing buildings has been receiving significant attention recently, which entails reducing energy demand for building operations, without affecting the health and comfort of its occupants. This approach requires strategies beyond mere technical advancements. However, there is limited published literature which has comprehensively addressed these issues. The aim of this paper is to critically review existing body-of-the-knowledge on improving energy efficiency of operating both commercial and institutional buildings. Peer-reviewed journal articles published from year 2000 to 2014 in reputed journals were reviewed. This review investigated contemporary energy efficiency approaches including technical, organizational, and behavioural changes. Based on the comprehensive literature review, a strategy map was developed as a pathway for achieving better building energy performance. It was noted that even though the existing studies predominately focused on technical advancements, approaches such as building behavioural changes have been largely overlooked. Findings of this study provide an important basis for setting up a national and organization wide strategy for improving the energy efficiency of commercial and institutional buildings. [ABSTRACT FROM AUTHOR]

Procurement is a key process in construction project management. The current construction procurement practices have been widely criticized for disregarding sustainability in the project life cycle. At present, there is a gap of knowledge on status-quo of sustainable procurement in Canada. Therefore, the objective of this study is to review sustainable procurement practices in the Canadian construction industry. A multi method research design was used in this study by combining both qualitative and quantitative research methods. Three research tools were used in the study; namely questionnaire surveys, review of documents, and semi-structured interviews. Data triangulation was used to combine the results of all three research tools. The study showed that sustainable procurement initiatives have rarely been used in the Canadian construction industry. Limited sustainability initiatives are used in the project procurement, while environmental sustainability criteria are given the prominence. Furthermore a significant deficiency is observed in bid evaluation involving triple bottom line of sustainability. A majority of construction industry respondents agreed that sustainable procurement is a long due necessity and highlighted government regulations as the main driver for sustainable procurement. This study may be the first step to promote the use of sustainable procurement in the Canadian construction sector. [ABSTRACT FROM AUTHOR]

Disregard of triple bottom line (TBL) of sustainability is one of the major drawbacks of current construction procurement practices. Sustainable procurement is an emergent concept that can improve procurement practices and enhance the sustainability performance of the construction industry as a whole. Presently, sustainable procurement is still not fully utilized in the Canadian construction industry. A comprehensive literature review showed that the construction industry is still not fully aware about the benefits of using sustainable procurement or ways of implementing the same. This study evaluates challenges encountered in implementing sustainable procurement in the Canadian construction industry. In addition, this study investigates perceptions of construction professionals on the benefits of using sustainable procurement for construction projects. A country wide questionnaire survey and semi-structured interviews were conducted to collect required data. A statistical analysis was performed to rank the challenges and benefits of sustainable procurement. Findings from semi-structured interviews were used to validate the results observed in the statistical analysis. This study revealed that lack of funding is the main challenge for implementing sustainable procurement, while reducing harmful emissions and waste generation was identified as the main benefit. It was concluded that the leadership and commitment of the project owners is the key to fully establish sustainable procurement in the Canadian construction industry. [ABSTRACT FROM AUTHOR]

Procurement is a key process in a construction project that creates and manages contacts. Procurement activities span from identification of requirements to project closeout, making it a perfect mode for integrating organizational strategic directions. Lately, the strategic importance of procurement has been widely acknowledged by academics as well as industry professionals. Construction procurement is a complex process with a large number of available options and directions. Ad hoc statistics show that modern initiatives such as sustainability, life-cycle costing, and standardization are getting integrated with procurement. However, there is no unified view in the construction industry on procurement as a project process. This paper presents a comprehensive review of traditional and emerging procurement practices in the construction industry. The current procurement practices are analyzed by separating into three segments; processes, methods, and policies. Furthermore, strengths and weaknesses of the traditional procurement methods are reviewed in detail. As the final section, contemporary developments in construction procurement are investigated. This article consolidates detailed knowledge of construction procurement that is identified as a knowledge gap in the literature. [ABSTRACT FROM AUTHOR]

• Experimental investigation of the lateral coupling in rectangular elastomeric isolators. • Three types of bidirectional loading were considered using a 6DOF apparatus. • An analytical model was derived and validated for the force-displacement relationship. • Conclusions based on the lateral stiffness, damping, and residual displacement. Elastomers are ideal for application as base isolators due to their ability to accommodate large recoverable strains. The formation of a composite with reinforcement, either steel or fibers, takes advantage of the near incompressibility of the elastomer to enhance the vertical and bending properties of the bearing. Although the conceptual design of a fiber-reinforced and steel-reinforced elastomeric bearing is similar, the lack of flexural rigidity of the fiber reinforcement results in unique performance characteristics, especially in the lateral direction. In this paper, an experimental program is conducted to evaluate the effect of lateral coupling in rectangular unbonded fiber-reinforced elastomeric isolators (UFREIs). An apparatus with six degrees of freedom was used to apply a vertical load with simultaneous displacement in both primary lateral directions, whereas previous experimental programs are mostly based on a two degree of freedom analysis (vertical and lateral). The UFREI specimen was subjected to cyclic lateral displacements including tests with initial lateral offsets in the secondary lateral direction, in directions angled off the principal lateral axis, and in a circular motion. This experimental program is the first to investigate lateral coupling in rectangular UFREIs. A comparison was conducted based on the effective lateral stiffness, equivalent viscous damping, and energy dissipation characteristics. The considered rectangular UFREIs were found to exhibit lateral coupling but the degree of coupling and the impact on the structural performance under bidirectional loading require further investigation. Residual displacement was observed in the experimental program and is discussed in depth. Also, a theoretical equation is derived to calculate the lateral stiffness based on the angle of loading and lateral displacement. Theoretical values are compared with experimental results to verify the equation. [ABSTRACT FROM AUTHOR]

During the recent past, the individual responsibility of climate change mitigation has been acknowledged by the society at large. Energy planning is pivotal in mitigating GHG emissions and adopting climate resilient strategies. However, community level energy planning has been overlooked in the urban development planning and the approval process. Many energy and emission reduction approaches are still voluntary for the developers and been pursued on ad-hoc basis. The objective of this study is to propose a systematic framework for renewable energy integration in community development. A scenario-based study was conducted for an upcoming neighbourhood in Okanagan, British Columbia (BC), Canada. Scenarios were assessed based on the life cycle cost (LCC) and GHG emission reduction. The scenarios were then compared based on costs and benefits to key stakeholders. Results of this study revealed that a higher share of renewable sources in the energy mix does not necessarily reduce LCC or GHG emissions. The benefits which can be achieved via incorporating renewables to the regional energy mix varies, depending on the existing energy sources in the mix. Therefore, regional power grid mix influences the feasibility and acceptability of RE integration at a given location. Developers should be aware of the optimal investment level which could be fully or partially recovered by premium home prices. The government should promote this practice via various incentives such as tax credits, grants etc. Findings of this research would mainly inform urban developers in renewable energy planning and local government in formulating climate action policies. [ABSTRACT FROM AUTHOR]

Occupant behavior in residential buildings has a direct impact on the effectiveness of energy-saving measures. In order to realize a buildings' carbon mitigation targets, the impact of individual occupancy profiles needs to be integrated with building simulation models. This paper introduces a decision support framework as a potential solution to make energy performance upgrade choices based on different occupancy profiles. This framework has been demonstrated through a case study of two single-family detached homes in Canada, which were highly instrumented with sensors for monitoring energy input and output. The case studies represented two common occupancy profiles-(1) a family of four (consisting of 2 working adults and 2 teenagers); and (2) a retired couple. Firstly, calibrated energy models were developed by using one-year energy use data collected through an intrusive load monitoring technique. Secondly, energy upgrade combinations were considered for each profile and tested for additional investment, payback period and greenhouse gas (GHG) emissions. Lastly, the most suitable combination of energy upgrade for each profile was ranked using a multi-criteria decision-making method (e.g., TOPSIS). Results indicated that the retired couple used more energy than the family of four and required energy upgrades with usually higher payback periods to achieve the same level of GHG emission reduction. The results of this research are timely for energy policymaking and developing best management practices, which need to be implemented along with the deployment of more stringent building standards and codes. • A scenario-based framework was developed for residential homes energy upgrades. • It considers occupant behavior and preference in selecting energy upgrades. • Field data is used to represent energy use of a family of four and a stay-at-home retired couple. • Energy upgrades are same under pro-economic choices for two profiles. • Energy upgrades vary under pro-environmental scenarios for two profiles. [ABSTRACT FROM AUTHOR]

Supplying the energy needs of a community through renewable energy sources is a vital aspect in developing sustainable communities. Many variations and uncertainties affect the development of a renewable-powered net-zero energy system. Community developers face challenges in making the investment decisions when planning community-level renewable energy (RE) projects. This study aims to address the need for reliable methods to assess RE project deployment strategies. To achieve this, the key decision variables were identified and dynamic project performance was assessed for a Canadian RE case study. A framework was developed using system dynamics for rating renewable energy project deployment scenarios. A fuzzy logic-based optimization process was used to identify the optimal system capacities and energy mix. The optimal energy supply mix was identified as follows for the case study: grid electricity- 56%, solar PV – 28%, biomass – 11%, and waste-to-energy– 5%. The results of the system dynamics based rating indicated that stage-by-stage construction that also accounts for community growth in facility capacity sizing provides the best outcomes for the community, with 42.8% of the community's energy demand supplied with renewables. The developed model can help community developers to identify the best energy choices and investment strategies when planning community energy systems. • Energy planning involved technical, economic, and environmental dimensions. • Planning hybrid RE systems at community level supports net-zero development. • Multi-objective optimization is used to identify the optimal energy supply mix. • System dynamics modelling is used to evaluate long-term RE project performance. • Phased development with capacity growth is a better choice for community RE. [ABSTRACT FROM AUTHOR]