桥梁工程全寿命周期碳排放流计算与分析

为了探寻不同类型桥梁全寿命周期碳排放的差异，基于全寿命周期理论将桥梁工程寿命周期划分为物化、运营维护以及拆除报废3个阶段。选取6种不同类型的桥梁，对其碳排放数据进行归一化处理，得到各阶段的碳排放流。进而借鉴现金流量理论构建了静态及动态的桥梁碳排放流模型，并通过此模型对上述桥型的碳排放流进行了分析。研究结果表明：静态碳排放总流从大到小依次为刚构桥(684.016)、斜拉桥(598.778)、悬索桥(461.288)、连续梁桥(264.728)、拱桥(218.508)、简支梁桥(45.009)。动态碳排放总流从大到小依次为刚构桥(12 446.639)、悬索桥(10 180.505)、斜拉桥(8 963.715)、连续梁桥(4 853.203)、拱桥(4 529.216)、简支梁桥(883.095)。本项研究提出的桥梁碳排放流模型，充分考虑了碳排放的时间价值，可更好地指导桥梁选型，助力桥梁工程的低碳、环保、可持续发展。

Calculation and analysis of life-cycle carbon emission flow of bridge engineering

In order to explore the differences of carbon emissions in the full life cycle of different types of Bridges, the life cycle of bridge engineering is divided into three stages: materialization, operation and maintenance, demolition and scrapping based on the life cycle theory. The carbon emission data of six different types of Bridges in the literature were normalized to obtain the carbon emission flows of each stage. Then, the static and dynamic carbon emission flow models of Bridges are constructed based on the cash flow theory, and the carbon emission flow of the above Bridges is analyzed through this model. The results show that the total static carbon emission flows from large to small are rigid frame bridge (684.016), cable-stayed bridge (598.778), suspension bridge (461.288), continuous beam bridge (264.728), arch bridge (218.508) and simply supported beam bridge (45.009). The total dynamic carbon emission flow of rigid frame bridge (12446.639), suspension bridge (10180.505), cable-stayed bridge (8963.715), continuous beam bridge (4853.203), arch bridge (4529.216) and simply supported beam bridge (883.095) in order from largest to smallest. The bridge carbon emission flow model proposed in this study fully considers the time value of carbon emission, which can better guide the bridge selection and help the low-carbon, environmental protection and sustainable development of bridge engineering.