人工砂级配及石粉含量对ECC拉伸性能影响的机理
Mechanism of Influence of Artificial Sand Gradation and Stone Powder Content on ECC Tensile Properties
陈程琦 1李家正 2石妍 2徐金霞 1陈俊1
作者信息
- 1. 河海大学力学与材料学院,南京 211100
- 2. 长江水利委员会长江科学院,武汉 430010
- 折叠
摘要
通过拉伸性能试验研究了不同人工砂级配及石粉含量对水工ECC(Hydraulic Engineered Cementitious Com-posites,HECC)单轴拉伸性能的影响,并通过扫描电镜(SEM)分析不同人工砂级配与龄期对ECC的微观结构和拉伸断面处纤维状态的影响.结果表明:采用单级配和连续级配人工砂制备的水工ECC的抗拉强度随着龄期的增加而增大,其极限拉应变随着龄期的增大而减小.其中,人工砂粒径小于0.16 mm的单级配ECC无明显的多缝开裂现象.此外,随着石粉含量的增加,ECC的抗拉强度呈现增大的趋势,极限拉应变呈现下降的趋势.石粉掺量为15％的ECC拉伸性能最好,其7 d抗拉强度为4.08 MPa,极限拉应变为3.35％.
Abstract
The influence of different artificial sand gradations and stone powder content on the uniaxial tensile proper-ties of Hydraulic Engineered Cementitious Composites(HECC)was studied by tensile properties test.The effects of dif-ferent sand gradation and age on the microstructure and fiber state of ECC were analyzed by SEM.Results show that the tensile strength of hydraulic ECC prepared by single and continuous graded artificial sand increases with the increase of age,and the ultimate tensile strain decreases with the increase of age.Among them,the single graded ECC with artificial sand particle size less than 0.16 mm has no obvious multi-crack phenomenon.In addition,with the increase of stone pow-der content,the tensile strength of ECC showed a trend of increasing,and the ultimate tensile strain showed a trend of de-creasing.ECC with 15％stone powder content has the best tensile properties.7 d tensile strength and ultimate tensile strain of ECC are 4.08 MPa and 3.35％,respectively.
关键词
ECC/龄期/级配/拉伸性能/人工砂Key words
ECC/age/graded/tensile properties/artificial sand引用本文复制引用
基金项目
国家自然科学基金(52179122)
国家自然科学基金(U2040222)
湖北省自然科学基金(2022CFD026)
出版年
2024
NETL
NSTL
万方数据