T梁桥在建设期碳排放模型的建立与分析

Establishment and analysis of carbon emissions model of T-beam bridge during construction

为了对桥梁的低碳施工提供理论依据,首先对桥梁建设期碳排放计算的边界进行了界定,将建设期划分成材料生产、材料运输和机械施工三个阶段,应用因素分解理论及碳排放系数法建立了桥梁建设期的碳排放模型。然后以益阳至娄底高速公路的一段预制T梁桥作为研究对象,通过清单、计价文件和施工图纸确定了各种碳排放因子,计算出了该上部结构的碳排放量,基于此计算方法计算出了T梁桥各部位的碳排放量并进行了对比分析。最后将此碳排放模型中影响因素的不确定性也考虑进来,进行了参数敏感性分析。分析结果表明,T梁桥建设期的碳排放从结构考虑主要来源于桩基工程和上部工程;从建设期阶段考虑主要来源于生产阶段;T梁桥建设期的碳排放参数敏感性强度排序为:水泥碳排放因子>钢材碳排放因子>电力碳排放因子>柴油碳排放因子。

The analysis of carbon emissions during the construction period of T beam bridges can provide theoretical basis for low-carbon construction of bridges. This paper first defines the boundary of carbon emissions calculation during the bridge construction period, and di vides the construction period into three stages： material production, material transporta- tion, and mechanical construction. The carbon emission model of the bridge construction period is established by using the factor decomposition theory and the carbon emission cod ficient method. Taking a section of prefabricated T-beam Bridge from Yiyang to Loudi Ex- pressway as the research object, various carbon emission factors were determined through inventory, valuation documents and construction drawings, and the carbon emissions of the superstructure were calculated. Based on this calculation method, T beam bridge was calcu lated. The carbon emissions of various parts of the bridge were compared and analyzed. Fi- nally, the uncertainties of the influencing factors in this carbon emission model were also taken into account. The sensitivity analysis of the parameters was performed. The results show that： During the construction period of T bridge bridges, the main sources of carbon emissions are the main source of the structure, the pile foundation works and the upper part of the project- at the construction phase, they mainly come from the production phase; the carbon emission parameters of the T-bridge bridge construction period are sensitive to the intensity： cement carbon Emission Factor- Steel Carbon Emission Factor- Electricity Carbon Emission Factor- Diesel Carbon Emission Factor. The conclusion of this paper pro- vides a reference calculation model for the carbon emissions generated by the T beam bridge and provides a reference for the construction of low-carbon bridges.