冻融循环作用下聚丙烯纤维混凝土抗拉性能及孔隙结构特征
Tensile properties and pore structure features of polypropylene fiber reinforced concrete under freeze-thaw cycles
程功 1程亚丽 1赵立财 2周飞3
作者信息
- 1. 郑州工商学院,河南 郑州,451450
- 2. 中铁十九局集团第三工程有限公司,辽宁 沈阳,110136;台湾科技大学 营建工程系,台湾 台北,10607
- 3. 四川省地质工程勘察院集团有限公司,四川 成都,610032
- 折叠
摘要
为提高冻融环境下混凝土的力学性能,通过劈裂抗拉试验、核磁共振试验(NMR)研究不同聚丙烯纤维掺量及冻融循环次数下混凝土的抗拉性能及孔隙结构的发展情况.研究结果表明:聚丙烯纤维掺量与混凝土的劈裂抗拉强度、峰值拉应变正相关,冻融循环次数与劈裂抗拉强度呈负相关关系,与峰值拉应变正相关,混凝土孔隙体积与冻融循环次数正相关,与聚丙烯纤维掺量负相关;建立聚丙烯纤维掺量、冻融循环次数与劈裂抗拉强度的关系式;对混凝土劈裂抗拉强度影响最大的孔径为(100,500]μm,其次为(500,1 000]μm孔径,(10,100]μm孔径的影响较小.研究结果为改善冻融环境下混凝土的性能提供理论支撑.
Abstract
In order to improve the mechanical properties of concrete under freeze-thaw environment,the tensile properties of concrete and the development of pore structure under different polypropylene fiber content and freeze-thaw cycles were studied by splitting tensile test and nuclear magnetic resonance test(NMR).The research result shows that the content of polypropylene fibers is positively correlated with the splitting tensile strength and peak tensile strain of concrete.The number of freeze-thaw cycles is negatively correlated with the splitting tensile strength,but positively correlated with the peak tensile strain.The pore volume of concrete is positively correlated with the number of freeze-thaw cycles,but negatively correlated with the content of polypropylene fibers.A relationship formula was established between the content of polypropylene fibers,the number of freeze-thaw cycles,and the splitting tensile strength.The pore size with the greatest impact on the splitting tensile strength of concrete is(100,500]μm,followed by(500,1 000]μm,and the impact of pore size(10,100]μm is relatively small.The research results provide theoretical support for improving the performance of concrete in freeze-thaw environments.
关键词
混凝土/聚丙烯纤维/冻融循环/劈裂抗拉强度/峰值拉应变/孔隙结构Key words
concrete/polypropylene fibers/freeze-thaw cycles/split tensile properties/peak tensile strain/pore structure引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据