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This paper presents a case study of a proposed regulatory future-proofing framework for the construction industry. The update to the crystalline silica standard by the Occupational Safety a...

Infrastructure projects experience different regulatory impacts during permitting, operations, and decommissioning. However, no framework is in place to provide a foundation for infrastruct...

The objective of this study is to establish a framework for analyzing infrastructure dynamics affecting the long-term steady state, and hence resilience in civil infrastructure systems. To this end, a multi-agent simulation model was created to capture important phenomena affecting the dynamics of coupled human-infrastructure systems and model the long-term performance regimes of infrastructure. The proposed framework captures the following three factors that shape the dynamics of coupled human-infrastructure systems: (i) engineered physical infrastructure; (ii) human actors; and (iii) chronic and acute stressors. A complex system approach was adopted to examine the long-term resilience of infrastructure based on the understanding of performance regimes, as well as tipping points at which shifts in the performance regime of infrastructure occur under the impact of external stressors and/or change in internal dynamics. The application of the proposed framework is demonstrated in a case of urban water distribution infrastructure using the data from a numerical case study network. The developed multi-agent simulation model was then used in examining the system resilience over a 100-year horizon under stressors such as population change and funding constraints. The results identified the effects of internal dynamics and external stressors on the resilience landscape of infrastructure systems. Furthermore, the results also showed the capability of the framework in capturing and simulating the underlying mechanisms affecting human-infrastructure dynamics, as well as long-term regime shifts and tipping point behaviors. Therefore, the integrated framework proposed in this paper enables building complex system-based theories for a more advanced understanding of civil infrastructure resilience.

Dual water distribution systems have been proposed as a technological infrastructure solution to enhance the sustainability and resilience of urban water systems by improving performance and decreasing energy consumption. The dual system separately distributes non-potable water for outdoor demand and potable water for indoor demand. The objective of this study was to evaluate the long-term performance of dual water distribution systems versus singular systems under various scenarios of renewal strategies and demand fluctuations. To this end, a dynamic (time-dependent) simulation model was developed to capture long-term dynamics of water distribution infrastructure systems using empirical relationships. The model integrates utility agency’s renewal decision-making processes with the physical infrastructure degradation to simulate the long-term transformation of the pipeline network. Various system performance measures, including breakage, leakage, energy loss, level of service, and life-cycle costs, were simulated over a 50-year horizon. The simulation model was implemented using data from the City of Fort Collins, CO, and used to examine the long-term performance of the dual and singular water distribution systems. The analysis results enabled: (i) understanding the long-term transformation of water distribution systems; (ii) comparing different performance measures of dual and singular systems; and (iii) exploring the sensitivity of both systems to demand fluctuations.

More than one billion people will face water scarcity within the next ten years due to climate change and unsustainable water usage, and this number is only expected to grow exponentially in the future. At current water use rates, supply-side demand management is no longer an effective way to combat water scarcity. Instead, many municipalities and water agencies are looking to demand-side solutions to prevent major water loss. While changing conservation behavior is one demand-based strategy, there is a growing movement toward the adoption of water conservation technology as a way to solve water resource depletion. Installing technology into one&rsquo, s household requires additional costs and motivation, creating a gap between the overall potential households that could adopt this technology, and how many actually do. This study identified and modeled a variety of demographic and household characteristics, social network influence, and external factors such as water price and rebate policy to see their effect on residential water conservation technology adoption. Using Agent-based Modeling and data obtained from the City of Miami Beach, the coupled effects of these factors were evaluated to examine the effectiveness of different pathways towards the adoption of more water conservation technologies. The results showed that income growth and water pricing structure, more so than any of the demographic or building characteristics, impacted household adoption of water conservation technologies. The results also revealed that the effectiveness of rebate programs depends on conservation technology cost and the affluence of the community. Rebate allocation did influence expensive technology adoption, with the potential to increase the adoption rate by 50%. Additionally, social network connections were shown to have an impact on the rate of adoption independent of price strategy or rebate status. These findings will lead the way for municipalities and other water agencies to more strategically implement interventions to encourage household technology adoption based on the characteristics of their communities.