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Department of Urban and Environmental Engineering (Disaster Management Engineering)Seismic risk assessment has recently emerged as an important issue for infrastructure systems because of their vulnerability to seismic hazards. Earthquakes can have significant impacts on transportation networks such as bridge collapse and the resulting disconnections in a network. One of the main concerns is the accurate estimation of the seismic risk caused by the physical damage of bridges and the reduced performance of the associated transportation network. This requires estimating the performance of a bridge transportation network at the system level. Moreover, it is necessary to deal with various possible earthquake scenarios and the associated damage states of component bridges considering the uncertainty of earthquake locations and magnitudes. To perform the seismic risk assessment of a bridge transportation network, system reliability is required. It is a challenging task for several reasons. First, the seismic risk itself contains a great deal of uncertainty, which comprises location, magnitude, and the resulting intensity of possible earthquakes in a target network. Second, the system performance of a bridge transportation network after the seismic event needs to be estimated accurately, especially for realistic and complex networks. Third, the seismic risk assessment employing system reliability may increase the computational costs and can be time-consuming tasks, because it requires dealing with various possible earthquake scenarios and the resulting seismic fragility of component bridges. Fourth, a precise performance measure of the system needs to be introduced. In this study, a new method is proposed to assess the system-level seismic risk of bridge transportation networks considering earthquake uncertainty. In addition, a new performance measure is developed to help risk-informed decision-making regarding seismic hazard mitigation and disaster management. For the tasks, first of all, a matrix-based system reliability framework is developed, which performs the estimation of a bridge transportation network subjected to earthquakes. Probabilistic seismic hazard analysis (PSHA) is introduced to enable the seismic fragility estimation of the component bridges, considering the uncertainty of earthquake locations and magnitudes. This is systemically used to carry out a post-hazard bridge network flow analysis by employing the matrix-based framework. Secondly, two different network performance measures are used to quantify the network performance after a seismic event. Maximum flow capacity was originally used for a bridge transportation network, however the numerical example using this measure is further developed for applications to more accurate system performance analysis using total system travel time (TSTT). Finally, a new method for system-level seismic risk assessment is proposed to carry out a bridge network flow analysis based on TSTT by employing the matrix-based system reliability (MSR) method. In the proposed method, the artificial neuron network (ANN) is introduced to approximate the network performance, which can reduce the computational cost of network analysis. The proposed method can provide statistical moments of the network performance and component importance measures, which can be used by decision-makers to reduce the seismic risk of a target area. The proposed method is tested by application to a numerical example of an actual transportation network in South Korea. In the seismic risk assessment of the example, PSHA is successfully integrated with the matrix-based framework to perform system reliability analysis in a computationally efficient manner.clos

Climate Change Impact Assessment for Surface Transportation in the Pacific Northwest and Alaska

WA-RD 772.

The State of Adaptation in the United States: An Overview

Over the past two decades the adaptation landscape has changed dramatically. From its early days as a vague theoretical concept, which was often viewed as a threat to advocating for the reduction of greenhouse gas emissions, it has developed into a widely, albeit not universally, recognized governmental mandate to reduce societal vulnerability to climate change. While it is important to appreciate the progress that we are making on this issue, it is impossible to ignore the urgent need to do more. Smart investment can be made by reflecting on what is already underway in order to determine where to build on existing efforts and where to innovate new approaches to fill the gaps in the path forward. In this report we provide illustrative examples of the variety of work on climate change adaptation that is underway in the United States. This is by no means an exhaustive survey of the field; however it does provide insight into the dominant focus of work to date, the resultant gaps, and the opportunities available for advancing this essential aspect of sustainability. We focus on four areas of activity -- agriculture, natural resources, human communities, and policy. The general trends relevant to these sectors can be applied more broadly to other sectors and countries. Adaptation can be thought of as a cycle of activities that ultimately -- if successful -- reduces vulnerability to climate change. This process starts with identifying the impacts of climate change to determine the types of problems climate change might pose. This includes all of the research on the causes and the global, regional, and local manifestations of climate change, often referred to as impacts assessments

Enhancing Ontario’s Rural Infrastructure Preparedness: Inter-Community Service Sharing in a Changing Climate — Environmental Scan

Given the research that has been done in this environmental scan and the gaps found in this research, it is our aim to find out: What types of service sharing are going on in Ontario municipalities, particularly in rural/remote areas? How can inter-community service sharing (ICSS) benefit the asset management planning process in these rural/remote areas to enhance capacities for climate change resilience? Climate change (CC) will exacerbate deterioration to existing infrastructure and increase replacement costs. Improved preparedness reduces risks and increases efficiency, readiness and coping capacity. To increase the preparedness of Ontario rural communities, this project develops CC-Prepared Inter-Community Service Sharing (ICSS) as an innovative strategy that expands cost-effective solutions within Ontario’s standardized Asset Management Planning (AMP) process. Overseen by a Project Advisory Board (PAB), it identifies a suite of best practice ICSS processes and principles and a range of factors and indicators that influence the uptake of ICSS as a viable and practical opportunity targeted to enhance rural infrastructure preparedness for CC. It utilizes a multimethod, interdisciplinary approach involving an environmental scan, interviews, a survey and case studies and develops an ICSS Toolkit consisting of reports, workbook, policy brief and media kit. Knowledge translation and transfer (KTT) includes blogs, teleconferences, articles, presentations and a workshop. For small rural Ontario communities, this study enhances management of CC impacts on infrastructure through the development of a CC-Prepared ICSS strategy, increasing anticipatory, collective actions that reduce dam age and increase efficiencies. It informs sound municipal/provincial level programs and policies about innovative ICSS that benefit rural communities through the identification of Ontario-wide trends, case study best practises and action-oriented recommendations

Carbon Free Boston: Social equity report 2019

OVERVIEW: In January 2019, the Boston Green Ribbon Commission released its Carbon Free Boston: Summary Report, identifying potential options for the City of Boston to meet its goal of becoming carbon neutral by 2050. The report found that reaching carbon neutrality by 2050 requires three mutually-reinforcing strategies in key sectors: 1) deepen energy efficiency while reducing energy demand, 2) electrify activity to the fullest practical extent, and 3) use fuels and electricity that are 100 percent free of greenhouse gases (GHGs). The Summary Report detailed the ways in which these technical strategies will transform Boston’s physical infrastructure, including its buildings, energy supply, transportation, and waste management systems. The Summary Report also highlighted that it is how these strategies are designed and implemented that matter most in ensuring an effective and equitable transition to carbon neutrality. Equity concerns exist for every option the City has to reduce GHG emissions. The services provided by each sector are not experienced equally across Boston’s communities. Low-income families and families of color are more likely to live in residences that are in poor physical condition, leading to high utility bills, unsafe and unhealthy indoor environments, and high GHG emissions.1 Those same families face greater exposure to harmful outdoor air pollution compared to others. The access and reliability of public transportation is disproportionately worse in neighborhoods with large populations of people of color, and large swaths of vulnerable neighborhoods, from East Boston to Mattapan, do not have ready access to the city’s bike network. Income inequality is a growing national issue and is particularly acute in Boston, which consistently ranks among the highest US cities in regards to income disparities. With the release of Imagine Boston 2030, Mayor Walsh committed to make Boston more equitable, affordable, connected, and resilient. The Summary Report outlined the broad strokes of how action to reach carbon neutrality intersects with equity. A just transition to carbon neutrality improves environmental quality for all Bostonians, prioritizes socially vulnerable populations, seeks to redress current and past injustice, and creates economic and social opportunities for all. This Carbon Free Boston: Social Equity Report provides a deeper equity context for Carbon Free Boston as a whole, and for each strategy area, by demonstrating how inequitable and unjust the playing field is for socially vulnerable Bostonians and why equity must be integrated into policy design and implementation. This report summarizes the current landscape of climate action work for each strategy area and evaluates how it currently impacts inequity. Finally, this report provides guidance to the City and partners on how to do better; it lays out the attributes of an equitable approach to carbon neutrality, framed around three guiding principles: 1) plan carefully to avoid unintended consequences, 2) be intentional in design through a clear equity lens, and 3) practice inclusivity from start to finish