摘要
研究了不同预湿和不同取代率再生细骨料对超高性能混凝土(UHPC)的抗压强度、自收缩、抗氯离子渗透性能影响。结果表明:再生细骨料的预湿程度和掺量是影响UHPC力学性能和自收缩的关键因素。不同预湿程度再生细骨料均能降低其早期自收缩,而对其早期抗压强度和抗氯离子侵蚀能力有不利影响,但提升其28d抗压强度;随着预湿再生细骨料掺量增大,UHPC自收缩逐渐降低,其中掺20%全预湿再生细骨料制备的UHPC抗压强度与抗氯离子渗透性能更优,与未掺再生细骨料UHPC相比,其28d抗压强度提升16.6%,自收缩降低了74.5%;预湿再生细骨料体孔隙水释放出来起到内养护的作用,降低UHPC内部自干燥进程,提高水化反应程度,优化界面过渡区组成结构,提高抗压强度和耐久性。
The effects of different prewetting and different substitution rates of recycled fine aggregate on compressive strength,autogenous shrinking and chloride penetration resistance of ultra-high performance concrete(UHPC)were studied.The results show that the degree of prewetting and the amount of recycled fine aggregate are the key factors affecting the mechanical properties and autogenous shrinking of UHPC.Recycled fine aggregate with different prewetting degree can reduce its early autogenous shrinking,which has adverse effects on its early compressive strength and chloride ion erosion resistance,but increases its 28d compressive strength.With the increase of prewet reclaimed fine aggregate content,the self-shrinking of UHPC gradually decreased.The compressive strength and chloride ion penetration resistance of UHPC prepared by adding 20%fully prewet reclaimed fine aggregate were better.Compared with unadded reclaimed fine aggregate UHPC,the 28d compressive strength increased by 16.6%and the self-shrinking decreased by 74.5%.The pore water released from the pre-wet reclaimed fine aggregate body plays the role of internal maintenance,reduces the internal self-drying process of UHPC,improves the degree of hydration reaction,optimizes the composition of the interface transition zone,and improves the compressive strength and durability.
作者
吴子杨
陈康
游啸
程书凯
WU Zi-yang;CHEN Kang;YOU Xiao;CHENG Shu-kai(School of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan 430073,China)
出处
《价值工程》
2023年第33期80-82,共3页
Value Engineering
基金
武汉工程大学研究生创新基金,氧化镁基膨胀剂-再生砂超高性能混凝土收缩性能的调控机理研究,基金编号(CX2022187)。
关键词
超高性能混凝土
再生细骨料
抗压强度
自收缩
电通量
ultra-high performance concrete
recycled fine aggregate
compressive strength
autougenous shrinkage
electric flux
