(1 甘肃省工程设计研究院有限责任公司, 兰州 730030; 2 扬州大学建筑科学与工程学院, 扬州 225127;3 江苏省装配式建筑与智能建造工程研究中心, 宿迁 223800; 4 扬州市房屋安全鉴定中心, 扬州 225002)

摘要: 为研究水胶比、减水剂和矿物掺合料掺量对超高性能混凝土(UHPC)工作性能的影响以及水胶比、矿物掺合料和钢纤维掺量对 UHPC 力学性能的影响,分别进行净浆流动度试验和 UHPC 抗折、抗压强度试验. 结果表明:提高水胶比和增加粉煤灰掺量可以改善浆体的流动性,但会降低 UHPC 的抗折强度和抗压强度;增加矿渣粉掺量可以在改善浆体流动性的同时,提高 UHPC 后期的抗折强度和抗压强度;随着硅灰掺量的增加,浆体的流动性不断降低,而 UHPC 的抗折强度和抗压强度呈现先上升后下降的趋势,当硅灰掺量为 25%时,UHPC 的强度达到峰值,抗折强度和抗压强度分别提高 23. 7%和 32. 0%;钢纤维掺量的增加会提高 UHPC 强度,当掺入 2%的钢纤维时,UHPC 的抗折强度与抗压强度分别提高 39. 7%和 59. 1%. 综合考虑,建议硅灰掺量在 20% ~ 30%之内为宜,矿渣粉掺量不超过 30%,粉煤灰掺量不超过 20%,钢纤维掺量宜取 2%.

关键词: 超高性能混凝土; 流动性; 力学性能; 抗压强度; 抗折强度;矿物掺合料;钢纤维

中图分类号:TU528 文献标志码:A 文章编号:1002-848X(2023)02-0142-06

DOI:10. 19701 / j. jzjg. LS210329

Analysis on working and mechanical properties of ultra-high performance concrete

YAO Shan1, YANG Zhongping1, GE Wenjie2,3, HU Yuexiang4, LI Wei2,SUN Chuanzhi3, YAN Weihua2, CAO Dafu2

(1 Gansu Engineering Design Research Institute Co. , Ltd. , Lanzhou 730030, China; 2 College of Civil Scienceand Engineering, Yangzhou University, Yangzhou 225127, China; 3 Jiangsu Province Engineering Research Centerof Prefabricated Building and Intelligent Construction, Suqian 223800, China; 4 Yangzhou Housing Safety Appraisal Center,Yangzhou 225002, China)

Abstract: In order to study the effects of water-binder ratio, water reducing agent content and mineral admixture content onthe working performance of ultra-high performance concrete ( UHPC) and the influence of water-binder ratio, mineraladmixture content and steel fiber content on mechanical properties of UHPC, the fluidity test of slurry and the flexural andcompressive strength test of UHPC were carried out respectively. The results show that increasing the water-binder ratio andfly ash content can improve slurry fluidity, but reduce the flexural strength and compressive strength of UHPC. The flexuralstrength and compressive strength of UHPC in later period can be improved by increasing the content of slag powder whileimproving slurry fluidity. With the increase of silica fume content, the slurry fluidity decreases continuously, while theflexural strength and compressive strength of UHPC increase first and then decrease. When the silica fume content is 25%,the strength of UHPC reaches the peak, and the flexural strength and compressive strength are improved by 23. 7% and32. 0% respectively. The increase of steel fiber content can improve the strength of UHPC, when 2% steel fiber is added,the flexural strength and compressive strength of UHPC are improved by 39. 7% and 59. 1% respectively. Consideringcomprehensively, it is recommended that the silica fume content should be within 20% ~ 30%, the slag powder contentshould not exceed 30%, the fly ash content should not exceed 20%, and the steel fiber content should be 2%.

Keywords: ultra-high performance concrete; fluidity; mechanical property; compressive strength; flexural strength;mineral admixture; steel fiber

∗甘肃省建设科技计划项目(JK2021-19),江苏省自然科学基金面上项目(BK20201436),江苏省装配式建筑与智能建造工程研究中心开放基金( 2021),江苏省建设系统科技项目( 2018ZD047、2021ZD06),扬州市市校合作资金项目( YZ2022194、YZU212105),扬州市建设科技项目(2022ZD03、202204).

第一作者:姚山,博士,高级工程师,主要从纤维混凝土结构方向的研究,Email:yaoshan8@ 126. com.

[引用本文] 姚山,杨忠平,葛文杰,等. 超高性能混凝土工作及力学性能分析[ J]. 建筑结构,2023,53(2):142-147. YAO Shan, YANG Zhongping, GE Wenjie, et al. Analysis on working and mechanical properties of ultra-highperformance concrete[J]. Building Structure,2023,53(2):142-147.