粉煤灰微珠和钢纤维掺量对UHPC扩展度及力学性能的协同影响研究  

Study on the collaborative impact of fly ash microspheres and steel fiber content on the expansion and mechanical properties of UHPC

作　　者：李永升 徐建光 王鹏刚[2] 原国健[1] 周少龙 刘绮轩 LI Yongsheng;XU Jianguang;Wang Penggang;YUAN Guojian;ZHOU Shaolong;LIU Qixuan(No.2 Engineering Company Ltd.of CCCC First Habor Engineering Company Ltd.,Qingdao 266071,China;School of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China)

机构地区：[1]中交一航局第二工程有限公司,山东青岛266071 [2]青岛理工大学土木工程学院,山东青岛266033

出　　处：《新型建筑材料》2025年第3期106-112,共7页New Building Materials

基　　金：国家自然科学基金项目(U22A20229);山东省自然科学基金项目(ZR2021ME081);中交第一航务工程局有限公司揭榜挂帅项目(2022-YHJJBGS-02)。

摘　　要：采用正交试验法研究了粉煤灰微珠掺量和钢纤维掺量对UHPC扩展度、抗压强度和弯曲韧性的影响,以及粉煤灰微珠对UHPC微观结构的影响。结果表明:UHPC的扩展度随粉煤灰微珠掺量增加而增大,随钢纤维掺量增加而减小;UHPC的抗压强度随钢纤维掺量增加而提高,28 d抗压强度随着粉煤灰微珠掺量增加而提高;UHPC的弯曲韧性强度随粉煤灰微珠和钢纤维掺量的增加而增大,同时建立了钢纤维掺量与UHPC弯曲韧性强度的拟合曲线;粉煤灰微珠具有填充作用,能够细化孔结构,使UHPC浆体更致密,当粉煤灰微珠掺量为15%、30%时,孔隙率相较于未掺粉煤灰微珠组分别减小了13.0%、61.7%。Orthogonal experiments were used to study the effects of different fly ash microbeads contents and steel fiber contents on the expansion,compressive strength,and flexural toughness of UHPC,as well as the effects of fly ash microbeads on the microstructure of UHPC.The results show that the expansion of UHPC increases with the increase of fly ash microbeads and decreases with the increase of steel fibers.The compressive strength of UHPC increases with the increase of steel fibers with the same content of fly ash microbeads,while the compressive strength at different ages decreases first and then increases with the increase of fly ash microbeads content at the same steel fiber content.The bending toughness index of UHPC increases with the increase of fly ash microbeads and steel fiber content,and the correlation between steel fiber content and UHPC bending strength is established.Fly ash microbeads have a filling effect,which can refine the pore structure and make the UHPC slurry more dense.When the content of fly ash microbeads is 15%and 30%,the porosity of the slurry decreases by 13.0%and 61.7%compared to the pure slurry without fly ash microbeads,respectively.

关 键 词：UHPC 粉煤灰微珠 钢纤维 扩展度 弯曲韧性 

分 类 号：TU528[建筑科学—建筑技术科学]