在全球溫室氣體減?趨勢之下，聯合國氣候變化綱要公約(United Nations Framework Convention on Climate Change，UNFCCC)會員國已於2009年第十五次締約國大會中提出哥本哈根協議(Copenhagen Accord)，說明應控制全球溫?上升?高於攝氏2度，並要求主要碳排放國家應提出其2020?的?化減?目標，因此減少二氧化碳排放，實為刻不容緩之議題。公路工程是台灣重大工程項目之一，其中以橋梁工程設計最複雜。當設計單位若採用不同的設計元素或結構型式等，將直接影響材料使用數量與施工時間，亦將造成相當程度之碳排放量差異。 本研究主要目的為擬定橋梁工程碳排放計算範疇，透過專家訪談與案例計算成果找出影響橋梁工程碳排放量之關鍵因素，並依計算之成果彙集橋梁工程主要碳排放工項。依據計算結果與分析顯示，橋梁工程可概分為上、下部結構，上部結構碳排放量主要受不同主梁材質、結構型式、跨度、是否為跨河橋與工法等，而下部結構依是否為跨河橋、橋墩高度以及基礎型式分類也有差異；主要碳排放工項彙整，混凝土I型橋梁共有16項主要碳排放工作項目、混凝土箱型梁15項、鋼橋17項，而混凝土橋主要以結構用混凝土與鋼筋材料為最主要碳排放工項，鋼橋則以鋼板為主。 Greenhouse effect and greenhouse gas mitigation practices are becoming global issues in recent years. The government in Taiwan has also developed policy to reduce CO2 emission and save energy in construction of public projects. The objective of this research is to identify the influencing factors on the CO2 emission of bridge construction projects in Taiwan. Examples of those factors are the type of superstructure, the type of lower structure, the construction methods, the location of the project, and so on. The rules of Carbon footprint are used to calculate the CO2 emission of around 31 bridge construction projects in Taiwan. Results of the calculation of these case projects are then compared to each other for analysis to identify the influencing factors on the CO2 emission of bridge projects in Taiwan. Public owners and designers can refer to those identified factors for constructing bridges with lower CO2 emission. The goal of reducing CO2 emission in construction can be facilitated.
