PDF全文阅读

尚  竞¹,陶文彬²

 

 

（1.江苏省人民医院基建处（南京医科大学第一附属医院）,南京  210029;

2.东南大学 土木工程学院,南京 214135）

摘要：为降低高性能混凝土（HPC）中硅酸盐水泥用量,采用不同钙含量、细度的粉煤灰替代40%水泥，研究了Ⅰ级高钙粉煤灰（HFA）、低钙粉煤灰（LFA）和Ⅱ级粉煤灰（ⅡFA）对HPC的抗压强度、氯离子渗透系数、吸水率、累计水化放热量的影响规律，并通过XRD分析了氢氧化钙残留量。结果表明:采用HFA或LFA替代40%水泥可制备HPC，90 d抗压强度较基准组分别提高86%和138%,HFA利于早期强度发展，LFA长期强度更高；掺粉煤灰HPC的提高抗氯离子渗透性能、降低吸水率，细度影响比氧化钙含量更为显著；掺粉煤灰可显著降低水化放热量,LFA较HFA放热量更低,细度仅影响早期放热速率;LFA中无定型硅铝酸玻璃体含量高于HFA，可充分消耗水泥水化氢氧化钙形成C-(A)-S-H凝胶，氢氧化钙残留量最低。研究成果可为不同类型粉煤灰替代水泥提供依据。

关键词：粉煤灰；氧化钙；高性能混凝土；抗压强度；氯离子渗透系数；水化放热

中图分类号：TU528

文献标志码：A

文章编号：1005-8249（2025）06-0001-07

DOI：10.19860/j.cnki.issn1005-8249.2025.06.001

 

 

SHANG Jing¹,TAO Wenbin²

 

 

(1.Jiangsu Province Hospital（The First Affiliated Hospital with Nanjing Medical University）,

 

Nanjing 210029,China;2.School of Civil Engineering,Southeast University,Nanjing 214135,China）

 

Abstract：To reduce the consumption of Portland cement in high-performance concrete (HPC),40% of the cement was replaced with fly ash of varying calcium content and fineness.The effects of Grade I high-calcium fly ash (HFA),low-calcium fly ash (LFA),and Class Ⅱ fly ash (ⅡFA) on the compressive strength,chloride ion permeability coefficient,water absorption rate,and cumulative hydration heat evolution of HPC.Residual calcium hydroxide content was analyzed via XRD.The results indicate that substituting 40% cement with HFA or LFA enables HPC production,with 90-day compressive strength increasing by 8.6% and 13.8% respectively compared to the control group.HFA promotes early strength development,while LFA yields higher long-term strength.The addition of fly ash improved the chloride ion permeability resistance and reduced the water absorption rate of HPC,with fineness having a more significant impact than calcium oxide content.Fly ash significantly reduced the hydration heat release,with LFA exhibiting lower heat release than HFA,and fineness only affecting the early heat release rate.LFA contained higher amorphous silicoaluminate glass phase than HFA,enabling complete consumption of cement hydration calcium hydroxide to form C-(A)-S-H gel,resulting in the lowest residual calcium hydroxide content.These findings provide a basis for substituting cement with different types of fly ash.

 

Key words：fly ash;calcium oxide;high-performance concrete;compressive strength;chloride ion permeability coefficient;hydration heat

 

基金项目：江苏省高等学校自然科学研究面上项目(23KJB560005)。

作者简介：尚竞（1980—），男，硕士，高级工程师，研究方向:土木工程建筑。

通信作者：陶文彬（1987—），男，博士研究生，助理研究员，研究方向:基础设施的全寿命周期管控、智慧建造与运维。

收稿日期：2025-09-10