不同类型挡土结构碳排放计算与评价

Calculation and Evaluation of Carbon Emission from Different Types of Retaining Structures

挡土结构在修建过程中因能源消耗会产生大量的二氧化碳,现有的研究成果关于挡土结构碳排放的研究报道较少。依托河北省新元高速公路改扩建路基加宽工程,并基于相关研究成果,将挡土结构全生命周期分为建材生产、建材运输、建造施工与运营维护4个主要阶段;针对这4个主要阶段,基于生命周期评价理论和碳排放系数法,建立了挡土结构的碳排放计算数学模型,得到返包式加筋土陡边坡、液态粉煤灰悬臂式挡墙和泡沫轻质土挡墙3种类型的挡土结构各阶段的碳排放量。研究结果表明,返包式加筋土陡边坡、液态粉煤灰悬臂式挡墙、泡沫轻质土挡墙的总碳排放量分别为-195.471 t、325.713 t和322.599 t。返包式加筋土陡边坡总碳排放量最少、泡沫轻质土挡墙次之、液态粉煤灰悬臂式挡墙最多,返包式加筋土陡边坡对于改善碳排放环境状况具有明显优势。研究成果可为相关挡土结构碳排放量计算与评价提供参考。

The energy consumption of retaining structures will produce a large amount of carbon dioxide during the construction process.There are few reports on the carbon emissions of retaining structures.Based on an actual project of widening and expanding the subgrade of Xin-Yuan Expressway in Hebei Province and relevant research results,the life-cycle of a retaining structure is divided into four main stages,i.e.production stage of building materials,transportation stage of building material,construction stage and stage of operation and maintenance.In view of these four main stages,the mathematical model of carbon emission calculation for retaining structures was established based on the life-cycle assessment theory and the carbon emission coefficient method.The carbon emissions of three types of retaining structures,including the wrapped reinforced steep slope,the liquid fly ash cantilever retaining wall and the foam light-weight retaining wall were obtained.Results show that the total carbon emissions of the wrapped reinforced retaining wall,the liquid fly ash cantilever retaining wall and the foam lightweight retaining wall were-195.471 t,325.713 t and 322.599 t respectively.The total carbon emission of the wrapped reinforced steep slope is minimum,followed by the foam light-weight retaining wall and the liquid fly ash cantilever retaining wall.The wrapped reinforced steep slope has obvious advantages in improving the carbon emission control.Results of this study could be adopted as references for the calculation and the evaluation of carbon emissions of related retaining structures.