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周志威，王杰，余中华，刘佳欣， 肖东

（ 成都城投城建科技有限公司 ， 四川成都 610500)

摘 要：为有效降低超高性能混凝土 (UHPC) 中钢纤维的使用成本，采用混掺不同长度钢纤维方式，对UHPC的基本工作性能和力学性能进行对比研究。结果表明：钢纤维长度对UHPC扩展度有一定影响，总体上长纤维混掺组的扩展度小于短纤维混掺组，钢纤维掺量比钢纤维长度对扩展度的影响更大；热水养护可以促进UHPC 中氢氧化钙迅速反应生成强度更高的 C - S- H 凝胶物质，热水养护3d 的UHPC力学强度明显高于标准养护28d的力学强度；热水养护混掺 8 、20 mm 长钢纤维的UHPC抗压强度最高，混掺16 、20mm 长钢纤维的UHPC抗折强度最高，标准养护混掺16 、20mm长钢纤维的UHPC抗压和抗折强度最高；通过层次分析法对UHPC综合性能进行计算分析，发现在采用13、20mm或者16 、20mm 混掺方案时，综合性能可以超过13mm 长钢纤维单掺3%的UHPC综合性能，通过混掺优化可使UHPC材料生产成本降低600 ~ 700元/m3 。

关键词：超高性能混凝土；钢纤维长度；混掺；层析分析法；综合性能

中图分类号：U444 

文献标志码：A 

文章编号：1005- 8249 (2024) 03- 0030- 05 

DOI：10.19860/j.cnki.issn1005-8249.2024.03.007

ZHOU Zhiwei, WANG Jie, YU Zhonghua, LIU Jiaxin, XIAO Dong

(Chengdu Chengtou Urban Construction Technology Co. ，Ltd. ，Chengdu 610500 , China)

Abstract : In order to effectively reduce the cost of steel fibres in ultra- high performance concrete ( UHPC) , a comparative study of the basic working and mechanical properties of UHPC was carried out by mixing different lengths of steel fibres . The results show that : the length of steel fibre has a certain effect on the degree of expansion of UHPC , in general , the degree of expansion of the long fibre mixing group is smaller than that of the short fibre mixing group , and the amount of steel fibre mixing has a greater effect on the degree of expansion compared with the length of steel fibre; hot water curing can promote the rapid reaction of calcium hydroxide to generate a higher strength of the C - S- H gel substance in UHPC , and the mechanical strength of the UHPC in hot water curing for 3 d is significantly higher than that of the standard curing. The mechanical strength of UHPC in hot water conditioning for 3d is significantly higher than that of standard conditioning for 28d; the compressive strength of UHPC with 8 and 20 mm steel fibres in hot water conditioning is the highest , the flexural strength of UHPC with 16 and 20 mm steel fibres in hot water conditioning is the highest , and the compressive and flexural strengths of UHPC with 16 and 20 mm steel fibres in standard conditioning are the highest; the comprehensive performance of UHPC was calculated through the hierarchical analysis , and the calculation and analysis of UHPC performance were found to be the highest with the mixing scheme of 13 and 20 mm or 16 and 20 mm. It is found that the comprehensive performance of UHPC with 13 and 20 mm or 16 and 20 mm mixing scheme can exceed the comprehensive performance of UHPC with 13 mm long steel fibre single mixing 3% , and the optimization of mixing can reduce the production cost of UHPC material by 600 ~ 700 RMB/m3 .

Keywords : ultra high performance concrete; steel fiber length; mixing; chromatography analysis method; comprehensive performance

作者简介：周志威 (1990—) , 男，硕士，工程师，研究方向： 市政 、水利 、建筑材料相关研究工作。

通信作者： 王 杰 (1990—) , 男，本科，工程师，研究方向： 市政 、桥梁方面研究工作。

收稿日期：2023-05-30