Effect of Raw Fly Ash on Performance of Ultra-High Performance Concrete

Abstract

Abstract: In order to improve the comprehensive utilization rate of fly ash and reduce the cost of raw materials, ultra-high performance concrete (UHPC) was prepared by the mass fraction of raw fly ash without grinding and sorting instead of silica fume. The effects of different amounts of raw fly ash on the mechanical properties and microstructure of UHPC were studied. The results show that the particle size distribution of cementitious material in UHPC is gradient, and good micro-grading can be formed by the addition of raw fly ash. The fluidity of fresh concrete increases and the distribution of steel fiber in UHPC matrix is affected. When the raw fly ash content does not exceed 30%, the flexural strength of UHPC increases in varying degrees with the increase of raw fly ash content.Compared with the blank sample without fly ash, the flexural strength of UHPC with 30% raw fly ash increases by 34%. In the range of 10% to 40% content of raw fly ash, due to the slow hydration of raw fly ash, the UHPC compressive strength decreases with the increase of replacement content of raw fly ash. The pore structure analysis shows that the average pore size and total pore volume of UHPC decrease with the addition of raw fly ash, and the matrix is more dense. When the raw fly ash content is 30%, SEM images show that the steel fiber is closely combined with UHPC matrix and the interfacial adhesion is enhanced.

Key words: ultra-high performance concrete, raw fly ash, mechanical property, pore analysis, microstructure

CLC Number:

TU528.2

SUN Jing, WANG Hong, LAN Jianwei, ZHOU Kai, LIU Hongbo. Effect of Raw Fly Ash on Performance of Ultra-High Performance Concrete[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(1): 209-217.

References

[1] LI J Q, WU Z M, SHI C J, et al. Durability of ultra-high performance concrete: a review[J]. Construction and Building Materials, 2020, 255: 119296.
[2] SOLHMIRZAEI R, SALEHI H, KODUR V, et al. Machine learning framework for predicting failure mode and shear capacity of ultra-high performance concrete beams[J]. Engineering Structures, 2020, 224: 111221.
[3] 张文华,张仔祥,刘鹏宇,等.多尺度纤维增强超高性能混凝土的轴心抗拉和抗压行为[J].硅酸盐学报,2020,48(8):1155-1167.
ZHANG W H, ZHANG Z X, LIU P Y, et al. Uniaxial tensile and compressive stress-strain behavior of multi-scale fiber-reinforced ultra-high performance concrete[J]. Journal of the Chinese Ceramic Society, 2020, 48(8): 1155-1167 (in Chinese).
[4] ZHONG C L, LIU M, ZHANG Y L, et al. Study on mix proportion optimization of manufactured sand RPC and design method of steel fiber content under different curing methods[J]. Materials, 2019, 12(11): 1845.
[5] AZMEE N M, SHAFIQ N. Ultra-high performance concrete: from fundamental to applications[J]. Case Studies in Construction Materials, 2018, 9: e00197.
[6] WANG Q W, SHI Q X, LUI E M, et al. Axial compressive behavior of reactive powder concrete-filled circular steel tube stub columns[J]. Journal of Constructional Steel Research, 2019, 153: 42-54.
[7] ZHENG W, XUE L V. Literature review of reactive powder concrete[J]. Journal of Building Engineering, 2015, 36: 44-58.
[8] DONG S F, HAN B G, OU J P, et al. Electrically conductive behaviors and mechanisms of short-cut super-fine stainless wire reinforced reactive powder concrete[J]. Cement and Concrete Composites, 2016, 72: 48-65.
[9] CHAN Y W, CHU S H. Effect of silica fume on steel fiber bond characteristics in reactive powder concrete[J]. Cement and Concrete Research, 2004, 34(7): 1167-1172.
[10] 陈志武.饱和面干再生细骨料对超高性能混凝土流动度及强度的影响[J].硅酸盐通报,2021,40(5):1503-1509.
CHEN Z W. Influences of saturated surface-dry recycled fine aggregate on fluidity and strength of ultra-high performance concrete[J]. Bulletin of the Chinese Ceramic Society, 2021, 40(5): 1503-1509 (in Chinese).
[11] 魏慧男,刘铁军,邹笃建,等.含废弃玻璃的绿色超高性能混凝土制备及性能[J].建筑材料学报,2021,24(3):492-498.
WEI H N, LIU T J, ZOU D J, et al. Preparation and properties of green ultra-high performance concrete containing waste glass[J]. Journal of Building Materials, 2021, 24(3): 492-498 (in Chinese).
[12] WU Z M, SHI C J, HE W. Comparative study on flexural properties of ultra-high performance concrete with supplementary cementitious materials under different curing regimes[J]. Construction and Building Materials, 2017, 136: 307-313.
[13] 苏捷,刘伟,史才军,等.超高性能混凝土立方体抗压强度尺寸效应[J].硅酸盐学报,2021,49(2):305-311.
SU J, LIU W, SHI C J, et al. Scale effect of cubic compressive strength of ultra-high performance concrete[J]. Journal of the Chinese Ceramic Society, 2021, 49(2): 305-311 (in Chinese).
[14] CHEN T F, GAO X J, REN M. Effects of autoclave curing and fly ash on mechanical properties of ultra-high performance concrete[J]. Construction and Building Materials, 2018, 158: 864-872.
[15] 钱觉时,吴传明,王智,等.模拟湿排粉煤灰的性能[J].硅酸盐学报,2007,35(7):871-876.
QIAN J S, WU C M, WANG Z, et al. Properties of simulative wetting fly ash[J]. Journal of the Chinese Ceramic Society, 2007, 35(7): 871-876 (in Chinese).
[16] 吴传明,钱觉时,侯鹏坤,等.湿排粉煤灰对混凝土性能的影响[J].土木建筑与环境工程,2009,31(5):132-137.
WU C M, QIAN J S, HOU P K, et al. Impacts of wetting fly ash on the properties of concrete[J]. Journal of Civil, Architectural & Environmental Engineering, 2009, 31(5): 132-137 (in Chinese).
[17] 李传炽,谢自标.湿排原状粉煤灰的综合利用研究[J].新型建筑材料,2002,29(11):31-33.
LI C C, XIE Z B. Study on comprehensive utilization of wet discharged undisturbed fly ash[J]. New Building Materials, 2002, 29(11): 31-33 (in Chinese).
[18] 孙婧,刘宏波,王宏,等.基于Design-expert的铁尾矿活性粉末混凝土配合比优化试验研究[J].硅酸盐通报,2020,39(3):762-769.
SUN J, LIU H B, WANG H, et al. Mix ratio optimization of reactive powder concrete with iron tailings based on design-expert[J]. Bulletin of the Chinese Ceramic Society, 2020, 39(3): 762-769 (in Chinese).
[19] 中华人民共和国国家质量监督检验检疫总局,中国国家标准化管理委员会.活性粉末混凝土:GB/T 31387—2015[S].北京:中国标准出版社,2015.
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, China National Standardization Administration Committee. Reactive powder concrete: GB/T 31387—2015[S]. Beijing: China Standards Press, 2015 (in Chinese).
[20] 中华人民共和国建设部,国家市场监督管理总局.混凝土物理力学性能试验方法标准:GB/T 50081—2019[S].北京:中国建筑工业出版社,2019.
Ministry of Construction of the People's Republic of China, State Administration for Market Supervision. Standard for test method for physical and mechanical properties of concrete: GB/T 50081—2019[S]. Beijing: China Construction Industry Press, 2019 (in Chinese).
[21] LIU K X, ZHU Z G, LI S K, et al. Preparation of UHPC with fly ash replaced by rich-silicon iron ore tailing powder[J]. Applied Mechanics and Materials, 2017, 872: 119-124.
[22] PARK S, WU S Y, LIU Z C, et al. The role of supplementary cementitious materials (SCMs) in ultra-high performance concrete (UHPC): a review[J]. Materials, 2021, 14(6): 1472.
[23] DUC VINH QUANG N, ALEKSANDROVA O, SAMCHENKO S. Combined effect of mineral admixtures and fine aggregate on the mechanical properties of ultrahigh performance concrete[J]. IOP Conference Series: Materials Science and Engineering, 2020, 869: 032034.
[24] 钟玲文,张慧,员争荣,等.煤的比表面积孔体积及其对煤吸附能力的影响[J].煤田地质与勘探,2002,30(3):26-29.
ZHONG L W, ZHANG H, YUN Z R, et al. Influence of specific pore area and pore volume of coal on adsorption capacity[J]. Coal Geology & Exploration, 2002, 30(3): 26-29 (in Chinese).