Gao Shan, Zhang Sumei, Guo Lanhui
School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China.
Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi'an 710123, China.
Materials (Basel). 2021 Nov 11;14(22):6803. doi: 10.3390/ma14226803.
Among the techniques for converting stacked coal gangue to reusable material, one of the most effective ways is to use coal gangue as a coarse aggregate in green concrete productions. The physical and chemical properties of rock and spontaneous-combustion coal gangue are generally suitable for being used as a coarse aggregate in green concrete. Coal gangue concrete is not recommended to be used in subsurface structures, as its water absorption law would be changed under a large replacement ratio. The mechanical performance of coal gangue concrete is degraded by raising the replacement ratio. Over-low and -high concrete grades are not suggested to be used as coal gangue aggregate, unless extra admixtures or specific methods are used. The influence of coal gangue on the durability of coal gangue concrete is remarkable, resulting from the porous structure of coal gangue that provides more transmission channels for air and liquid in concrete, but is beneficial for thermal insulation. The usage of coal gangue in structural concrete members is still limited. The mechanical behavior of some structural members using coal gangue concrete has been reported. Among them, concrete filled steel tubes are a preferable configuration for using coal gangue concrete, regarding both the mechanical and durability performance.
在将堆积煤矸石转化为可再利用材料的技术中，最有效的方法之一是在绿色混凝土生产中将煤矸石用作粗骨料。岩石和自燃煤矸石的物理和化学性质通常适合用作绿色混凝土中的粗骨料。不建议在地下结构中使用煤矸石混凝土，因为在高替代率下其吸水规律会发生变化。提高替代率会降低煤矸石混凝土的力学性能。除非使用额外的外加剂或特定方法，否则不建议使用过低和过高的混凝土等级作为煤矸石骨料。煤矸石对煤矸石混凝土耐久性的影响显著，这是由于煤矸石的多孔结构为混凝土中的空气和液体提供了更多传输通道，但有利于保温。煤矸石在结构混凝土构件中的应用仍然有限。已经报道了一些使用煤矸石混凝土的结构构件的力学性能。其中，就力学性能和耐久性而言，钢管混凝土是使用煤矸石混凝土的一种较好的结构形式。
