花岗岩废石料替代混凝土组分优先性试验

Priority Test of Granite Waste as a Substitute for Concrete Components

花岗岩废石料替代混凝土组分可以降低工程成本,减少天然资源消耗;确定替代的优先级,可更大程度实现对花岗岩废石料的再利用。为探究废石料等质量替代混凝土原材料的优先级,利用废石料分别替代水泥、粗细集料制备C25、C30、C40等3种强度混凝土,采用扫描电镜与压汞试验结合抗压强度试验结果分析废石料替代混凝土原材料后对混凝土强度、密实性的影响,确定替代的优先顺序。结果表明:C25、C30、C40等3种强度花岗岩废石料混凝土外观形貌优于同强度基准组,颗粒级配更为合理;3种混凝土中的无害孔、少害孔、有害孔和多害孔体积分布总体优于基准组,孔隙率分别为13.51%、11.52%、9.14%,与基准组相比都有显著降低。废石料的加入有效细化了裂缝与孔隙,提高了混凝土的强度和密实性,由此确定了替代混凝土组分的优先级,可为花岗岩废石料混凝土最优配合比设计提供参考。

Substituting granite waste for components in concrete can reduce project costs and decrease the consumption of natural resources.At the same time,determining the prioritization of this substitution can achieve greater reuse of granite waste material.To explore the priority of replacing concrete raw materials with granite waste of equal mass,waste stone was used to replace cement,coarse and fine aggregates respectively to prepare three types of strength concrete,including C25,C30,and C40.Scanning electron microscopy and mercury intrusion experiments,combined with compressive strength test results,are used to analyze the impact of substituting raw materials with waste stone on the strength and densification of concrete and determine the priority order of substitution.The results have shown that the appearance and morphology of C25,C30,and C40 granite waste stone concrete are superior to those of the corresponding strength reference groups,with more reasonable particle grading.The overall volume distribution of harmless pores,less harmful pores,harmful pores and more harmful pores in the three types of concrete is better than that of the reference group,with porosities of 13.51%,11.52%,and 9.14%,respectively,which have significantly decreased compared to the reference group.The addition of waste stone has effectively refined cracks and pores,increasing both the strength and densification of the concrete.Determines the substitution priority of concrete components,which can provides a reference for designing the optimal mix ratio of granite waste concrete.