我国铁路工程机制砂混凝土应用现状及存在问题

受天然河砂限采政策及季节性开采的制约,机制砂已经成为天然河砂的绿色替代品。针对我国铁路混凝土的工程特点,从石粉含量、颗粒级配、颗粒形貌等方面分析现行标准对机制砂的性能要求,论述机制砂混凝土性能特点,探讨机制砂在我国铁路现浇结构和预应力构件中应用现状及存在问题,提出应建立适应于铁路工程特点的机制砂标准体系、加强机制砂生产过程质量控制、深化机制砂混凝土结构性能研究等思路,以期规范和提升铁路工程机制砂混凝土的工程质量。

Application Status and Existing Problems of Manufactured Sand Concrete of Railway Engineering in China

Due to the limit of natural sand restriction policy and seasonal mining,manufactured sand has served as a green substitute of natural sand.In accordance with the engineering features of railway concrete in China,the paper analyzes the performance requirements of existing standard for manufactured sand from the aspects of limestone powder content,grain composition,particle morphology,etc.,discusses the performance features of manufactured sand concrete and the application status and existing problems of manufactured sand concrete of railway cast-in-place structure and prestressed components in China,then puts forward such ideas as establishing manufactured sand standard system suitable for railway engineering,reinforcing process quality control of manufactured sand and deepening performance research of manufactured sand concrete,with the purpose of standardizing and improving the engineering quality of railway manufactured sand concrete.