高速公路改扩建工程废弃混凝土再生骨料利用可行性分析

Feasibility analysis of using recycled concrete aggregate(RCA) in expressway reconstruction and expansion projects

在高速公路改扩建工程大规模发展的背景下,通过对我国天然骨料发展现状及问题、废弃混凝土对环境的影响以及高速公路改扩建工程投资控制需求3个方面分析,阐述了废弃混凝土再生骨料利用的必要性。对废弃混凝土再生骨料国内外研究现状进行了阐述,提出了适用于高速公路改扩建工程中废弃混凝土再生骨料的生产工艺,并对再生骨料相关技术指标进行了对比,论证了高速公路改扩建工程废弃混凝土再生骨料利用的技术可行性。同时依托江苏高速公路改扩建项目施工现场小规模生产模式,分别用成本法和定额法分析了再生骨料生产的微观经济性,说明了再生骨料相对于天然骨料的生产价格上有一定的优势,并从宏观经济的层面阐述了废弃混凝土再生骨料利用带来的社会效益和环境效益,进一步论证了废弃混凝土再生骨料利用的经济可行性,揭示了废弃混凝土再生骨料在高速公路改扩建工程应用的广阔前景。

With the increase of expressway reconstruction and expansion projects, the necessity of using recycled concrete aggregate is analyzed in three aspects: the current state and problems of natural aggregates use in China, the influence of scrap concrete on environment and the budget control requirement of expressway reconstruction and expansion(R&E) projects. The state of the practice of the utilization of recycled concrete aggregate in China and abroad is reviewed while the specific manufacturing practice RCA for expressway R&E projects is proposed. Several technical indexes for the QA/QC of recycled aggregate are compared and the technical feasibility of using RCA in expressway R&E project is then discussed. The small-scale field production of RCA in Jiangsu expressway R&E project is used as a case study for the microeconomic analysis of the utilization of RCA by the cost method and quota method respectively. The results show that RCA has some advantages of the production price over natural aggregates. Macroeconomic analysis concerning social and environmental benefits of the utilization of RCA is also conducted. Taking all these factors into account, It is concluded that the utilization of RCA has a wide prospect in expressway reconstruction and expansion project.