2009 年莫拉克颱風短短數天在南部地區即降下三千餘毫米之雨量，造成129座橋梁嚴重毀損、流失或遭土石流掩埋。因此，橋梁之維護策略如何因環境之變遷而調整，甚至是未來橋梁之重建、整建，以及新建，皆為國內交通與橋梁管理單位應審慎面對之問題。因規劃與設計階段為影響工程最重要之階段，故本研究將深入探討環境變遷對橋梁所造成之影響，並針對規劃與設計階段提出法規之改善方向或詳細說明。 本研究藉由莫拉克颱風災損橋梁致災原因之分析，以橋基、沖刷以及通水斷面為三大條件彙整橋梁設計相關之法規，先經由實地訪談橋梁之規劃、設計顧問公司，負責施工以及維護之營造廠商及負責管理橋梁之單位，了解法規原意及其內涵後，透過專家問卷篩選出需立即改善或應補充說明之條文，研擬應進行改善之方向或增加條文之詳細說明，最後再由專家確認本研究之成果。 本研究另針對橋梁規劃設計整體架構進行探討，透過專家訪談將其分為六大步驟，並依各步驟之施作要項提出需調整及應注意之重點。本研究並歸納出各地理位置、河寬、橋型與施工方法之組合，期以提供給設計者做參考。本研究之成果應可提昇未來新建橋梁安全防災之性能，進而達成橋梁永續使用之目的。 Typhoon Morakot hit southern Taiwan in 2009 and generated more than 3000mm rainfalls only in a few days. As a consequence, floods, land slides, floating timbers, debris flows, and sands and rocks in the floods severely damaged 129 bridges that caused interruptions in traffic as well as difficulties in the disaster mitigation processes. Thus, maintenance strategies in response to the global climate changes for existing bridges and for future renovation and reconstruction of bridges have become crucial issues to the bridge management agencies. This research aims at an in-depth investigation of impacts caused by global climate changes to the planning and design phases of bridges. Based on the factors that caused bridge damages due to the Morakot typhoon, this research investigated and summarized codes, specifications, and regulations that need to be changed in the design of pier foundations, scouring, and areas of water flow. Intensive interviews of experts in the design firms, construction contractors, maintenance contractors, and bridge management agencies were conducted to formulate and justify the required changes and suggestions. This research also concluded six steps for the planning and design of bridges based on interviews of experts. Focuses and reminders were suggested for each of the steps, especially for the selection of bridge site, type of bridge, and construction methods. Results of this research should be able to provide useful guidelines to the safety and sustainability of bridges.
