摘要
采用不同比表面积的凝灰岩粉取代30%水泥(按总胶凝材料质量计),研究了不同比表面积凝灰岩粉对水泥净浆流动度、胶砂强度、水化热的影响,以及凝灰岩粉取代水泥对碳排放量的影响。结果表明:比表面积381 m^(2)/kg的凝灰岩粉取代水泥可提升净浆初始流动度,但随着凝灰岩粉比表面积增大,净浆初始流动度明显降低;不同比表面积凝灰岩粉对3 d胶砂抗压强度的贡献与粉煤灰、矿渣粉相近,但对28、56 d胶砂抗压强度的贡献低于粉煤灰和矿渣粉;凝灰岩粉比表面积增大有利于提升胶砂抗压强度,但比表面积由495 m^(2)/kg增至700 m^(2)/kg时,对胶砂抗压强度的提升效果有限,综合考虑经济性和抗压强度,作矿物掺和料时凝灰岩粉宜磨细至比表面积495 m^(2)/kg;粉煤灰、矿渣粉和凝灰岩粉取代水泥均能降低水化放热速率峰值和72 h累计放热量,比表面积700 m^(2)/kg的凝灰岩粉对水泥水化进程的加速效果强于粉煤灰、矿渣粉和其他比表面积凝灰岩粉;495 m^(2)/kg比表面积的凝灰岩粉取代30%水泥后制成的复合胶凝材料,碳排放量降低29.5%。
The tuff powder with different specific surface areas(SSA)was used to replace 30%cement(calculated by the total mass of cementitious materials),and the effect of the tuff powder with different SSA on the paste flowability,mortar strength and cement hydration heat was studied.The effect of replacing cement with tuff powder on carbon emissions was analyzed.The results show that when replacing cement with the 381 m^(2)/kg SSA tuff powder,the paste initial flowability is improved,but as the SSA of tuff powder is increased,the initial flowability of paste is significantly decreased.The contribution of tuff powder with different SSA to the 3 d compressive strength of mortar is similar to that of fly ash and ground granulated blast furnace slag,but its contribution to the 28 d and 56 d compressive strength of mortar is lower than that of fly ash and ground granulated blast furnace slag.The increasing of the SSA of tuff powder is beneficial for improving the compressive strength of mortar,but the effect of improving strength is limited when the SSA of tuff powder is increased from 495 m^(2)/kg to 700 m^(2)/kg.Taking into account both economic and compressive strength of mortar,the tuff powder is suitable to grind to 495 m^(2)/kg SSA when it is used as a mineral admixture.The fly ash,ground granulated blast furnace slag and tuff powder all reduce the peak of hydration heat rate and 72 h cumulative heat of cement.The acceleration of tuff powder with the SSA of 700 m^(2)/kg for cement hydration is higher than that of fly ash,ground granulated blast furnace slag and other tuff powder.The composite cementitious material made by replacing 30%cement with 495 m^(2)/kg SSA tuff powder,reduces carbon emissions by 29.5%compared to 100%cement.
作者
林智
王振
洪伟华
黄法礼
杨志强
李化建
LIN Zhi;WANG Zhen;HONG Weihua;HUANG Fali;YANG Zhiqiang;LI Huajian(Zhejiang Communications Investment Mining Co.Ltd.,Zhoushan Zhejiang 316000,China;Railway Engineering Research Institute,CARS,Beijing 100081,China;State Key Laboratory for Track System of High-speed Railway,CARS,Beijing 100081,China)
出处
《铁道建筑》
北大核心
2024年第1期127-131,共5页
Railway Engineering
基金
中国国家铁路集团有限公司科技研究开发计划(J2022Z505)
中国铁道科学研究院集团有限公司基金(2021YJ078)
浙江省交通投资集团有限公司科技研发项目(202106)。
关键词
工程材料
凝灰岩粉
试验研究
水泥浆体
比表面积
胶砂
抗压强度
碳排放量
engineering materials
tuff powder
experimental research
cement paste
specific surface area
mortar
compressive strength
carbon emissions
