摘要
在以石灰石为原料制备机制砂的过程中容易产生大量石灰石粉,其会与水泥中铝酸三钙等矿相发生反应,具备一定的胶凝特性,将其加入混凝土取代部分水泥,可减少水泥在混凝土中的用量和碳排放量,提高石灰石粉资源化利用的效率,具有“减废减碳”的双重效果。本文比较了不同标准中石灰石粉的技术指标,将石灰石粉在混凝土中的作用分为填充效应、活性效应和晶核效应3个方面,并说明了石灰石粉对混凝土工作性能、力学性能和耐久性能的影响。现有研究表明:石灰石粉可以改善混凝土的工作性能,但同时会影响混凝土的力学性能,当纯水泥混凝土中石灰石粉的替代掺量为50%,或采用15%矿物掺合料进行复合掺配时,混凝土具备较好的工作性能和力学性能;石灰石粉会显著降低混凝土中浆体与颗粒之间界面过渡区的粘结强度,因此,随着石灰石粉掺量的提高,混凝土的耐久性逐渐降低。
In the process of preparing machine-made sand from limestone as raw material,a large amount of limestone powder is easily generated,which reacts with minerals such as tricalcium aluminate in cement and has certain cementitious properties.Adding it to concrete to replace some cement can reduce the amount of cement and carbon emissions,improve the efficiency of limestone powder resource utilization,with a dual effect of"waste reduction and carbon reduction".This article compares the technical indicators of limestone powder in different standards,and divides the role of limestone powder in concrete into three aspects:filling effect,active effect,and nucleation effect.It also explains the inf luence of limestone powder on the workability,mechanical properties,and durability of concrete.Existing research has shown that limestone powder can improve the workability of concrete,but at the same time,it can affect the mechanical properties of concrete.When the substitute dosage of limestone powder in pure cement concrete is 50%,or when 15%mineral admixture is used for composite mixing,the concrete has good workability and mechanical properties;limestone powder significantly reduces the bonding strength between the interface transition zone between the slurry and particles in concrete.Therefore,as the amount of limestone powder increases,the durability of concrete gradually decreases.
出处
《混凝土世界》
2025年第6期74-78,共5页
China Concrete
关键词
石灰石粉
技术标准
工作性能
力学性能
耐久性能
Limestone powder
technical standards
workability
mechanical properties
durability
