纳米SiO_(2)增强高掺量粉煤灰混凝土力学性能研究  

Study on the Properties of High-volume Fly Ash Concrete Incorporating Nano-SiO_(2)

作　　者：邓永刚[1] 赵冰洁 DENG Yonggang;ZHAO Bingjie(Shenyang Ligong University,Shenyang 110159,China)

机构地区：[1]沈阳理工大学材料科学与工程学院,沈阳110159

出　　处：《沈阳理工大学学报》2020年第6期55-60,共6页Journal of Shenyang Ligong University

基　　金：国家重点研发计划项目(2018YFD1101001);2020辽宁省教育厅科学研究经费项目(LG202019)。

摘　　要：为探明纳米粒子对高掺量粉煤灰混凝土微观结构力学性能的影响,采用TAM-Air、TG分析、SEM及力学性能测试等研究纳米SiO_(2)对高掺量粉煤灰混凝土力学性能的改善机制。对普通混凝土、高掺量粉煤灰混凝土、纳米SiO_(2)增强高掺量粉煤灰混凝土的水化过程、早期和后期强度、孔隙及微观结构进行比较。结果表明,纳米SiO_(2)掺入促进水泥的水化,提高粉煤灰的活性,降低高掺量粉煤灰混凝土的孔隙率,提高混凝土早期强度;与掺入前相比,7天抗压强度提高了78%;28天抗压强度与普通混凝土相当。同时,由于粉煤灰后期的水化作用,180天养护龄期下,粉煤灰混凝土的抗压强度与普通混凝土相比提高了4.2%。纳米SiO_(2)的掺入使高掺量粉煤灰混凝土的后期组织更致密。To explore the effect of nano-particles on the microstructure and properties of high-volume fly ash concrete,the mechanism of Nano-SiO_(2) to improve high-volume fly ash concrete was studied using TAM-Air,TG,SEM and mechanical properties tests in this paper.The hydration process,compressive strength of the concrete at early and later ages,porosity and impermeability of ordinary concrete,high content fly ash concrete and Nano-SiO_(2) modified high content fly ash concrete were analyzed.The results show that Nano-SiO_(2) can promote the hydration of high content fly ash concrete,reduce the porosity of high content fly ash concrete,improve the early strength of concrete,increase the compressive strength of 7 days by 78%,and the compressive strength of 28 days is similar to that of ordinary concrete.At the same time,the porosity of concrete was improved due to the hydration of fly ash in the later stage,and the later performance of high content fly ash concrete was enhanced.

关 键 词：纳米SiO_(2) 粉煤灰混凝土 水化过程 早期强度 孔隙率 

分 类 号：TU528.01[建筑科学—建筑技术科学]