Development of road network vulnerability analysis focusing on required functions immediately after a disaster

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14258
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22050:Civil engineering plan and transportation engineering-related
• Research Institution: Hokkaido University
• Principal Investigator: Satoshi Sugiura 北海道大学, 工学研究院, 准教授 (30648051)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 災害 / 道路網分析 / ネットワークデザイン問題 / グラフ理論 / 脆弱性

Outline of Final Research Achievements

This study aims to provide a method for evaluating the vulnerability of road networks and proposing improvement measures. Using the minimum cut theory, we developed two indicators to assess connection strength: isolation vulnerability and local capacity vulnerability, and constructed models to calculate these indicators. These indicators were applied to actual road networks to identify locations prone to isolation and areas expected to be congested during mass evacuations. Additionally, we formulated a network design problem to mitigate isolation vulnerability and identified new road sections to be added to reduce isolation vulnerability at key locations in northern Hokkaido. These research outcomes were published in two high-level academic journals and are considered to have received a certain level of recognition.

Free Research Field

土木計画，交通計画

Academic Significance and Societal Importance of the Research Achievements

本研究は災害直後に道路網が要求される性能，すなわち避難路としての冗長性，および孤立生起のしやすさを評価し，その水準を増強するための方策を与えるものである．構築したモデル群はいずれも実際の道路網で適用できることを確認しており，実務適用も可能であると考えている．構築した手法論は，以降の防災計画において資するところが小さくないと考える．