Research on application of emergency timber bridge for disaster

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04596
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 25030:Disaster prevention engineering-related
• Research Institution: Hakodate National College of Technology
• Principal Investigator: Hirasawa Hideyuki 函館工業高等専門学校, 社会基盤工学科, 教授 (90238353)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 木橋 / トラス橋 / 緊急仮設橋 / 架設実験 / 災害復旧

Outline of Final Research Achievements

The author develops a timber truss bridge as an emergency bridge for life saving and transportation of daily necessities. In the Warren truss bridge developed as emergency bridge in 2010, there was a problem of heat strain by welding in the steel connection plates. In another Warren truss bridge developed in 2019, the problem was removed without welded processing , however, deformation and vibration for the direction perpendicular to bridge axis occurred easily. To improve these problems, this study develops the bridge with the following characteristics ; (1) Using two steel plates with 3.2mm thickness for the connection, (2) Attaching the portal members to the intermediate part of the bridge as well as the end part of the bridge. (3) Using connection plates with folding processing, not welding processing. As the results, the bridge developed here became light and simple, and the construction time was only 3 hours and 8 minutes.

Free Research Field

橋梁工学

Academic Significance and Societal Importance of the Research Achievements

この研究で開発した木製トラス橋は、災害時を想定し電動工具類は使用せずスパナによるボルト締め作業のみで組み立て可能な優れた作業性、わずか3時間程度の急速施工で供用を可とする迅速性を有している。従来、橋は強度や耐久性を重視する設計思想で造られてきたが、災害復旧のための橋にはそれらとは異なる思想で考案する必要がある。特に、人命救助の観点から、被災後72時間以内の救出を果たすためには、被災地に関する情報収集の時間、被災地までの輸送時間、現地での架設時間を極力短縮しなければならない。この意味において、新しい思想を取り入れた学術的意義と架設時間の短縮化により迅速に復旧できる社会的意義がある。