膨胀剂与内养剂对超高性能混凝土性能的影响  

Effects of Expansive Agent and Super-Absorbent Polymer on Performance of Ultra-high Performance Concrete

作　　者：刘路明 方志[1,2] 黄政宇[1] 裴炳志 吴玉友 LIU Luming;FANG Zhi;HUANG Zhengyu;PEI Bingzhi;WU Yuyou(College of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory for Wind and Bridge Engineering of Hunan Province,Changsha 410082,China;Hubei provincial communications investment group,Wuhan 430070,China;College of transportation and civil buildings,Foshan University,Foshan 528225,Guangdong China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]湖南大学风工程与桥梁工程湖南省重点实验室,长沙410082 [3]湖北省交通投资集团有限公司,武汉430070 [4]佛山科学技术学院交通与土木建筑学院,广东佛山528225

出　　处：《硅酸盐学报》2020年第11期1706-1715,共10页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金项目(51878262);国家重点研发计划课题(2018YFC0705404)。

摘　　要：为降低或完全补偿超高性能混凝土(UHPC)的自收缩,研究了膨胀剂单掺、内养剂单掺、膨胀剂与内养剂复掺对UHPC的流动性、凝结时间、强度和自收缩的影响。结果表明:膨胀剂的加入明显降低和缩短了UHPC的流动性和凝结时间,内养剂的加入可以提高和延长掺膨胀剂UHPC的流动性和凝结时间;4%掺量的膨胀剂能小幅提高UHPC的强度,8%掺量的膨胀剂会降低UHPC的强度,内养剂的加入能改善掺8%膨胀剂UHPC的强度;4%掺量的膨胀剂能降低34.4%的自收缩,8%掺量的膨胀剂能完全补偿UHPC的自收缩,但存在体积安定性不良的问题,内养剂的加入能进一步降低掺4%膨胀剂UHPC的自收缩和改善掺8%膨胀剂UHPC的体积安定性。因此膨胀剂与内养剂复掺是一种较理想的用于降低UHPC自收缩的方法。In order to reduce or compensate the autogenous shrinkage of ultra-high performance concrete(UHPC), effects of expansive agent, super-absorbent polymer(SAP), expansive agent(EA) and SAP on the slump flow, setting time, strength and autogenous shrinkage of UHPC were investigated. The results show that EA can reduce the slump flow and shorten the setting time of UHPC, the addition of SAP increases the slump flow and the setting time of UHPC with EA. The EA addition of 4% can slightly increase the compressive and flexural strength of UHPC, the EA addition of 8% can decrease the compressive and flexural strength of UHPC, and the addition of SAP increases the compressive and flexural strength of UHPC with the EA addition of 8%. The autogenous shrinkage of UHPC is reduced by 34.4% at the EA addition of 4%, and the autogenous shrinkage of UHPC is compensated completely with a volume instability at the EA addition of 8%. The SAP addition can further reduce the autogenous shrinkage of UHPC at the EA addition of 4% and increase the volume stability of UHPC at the EA addition of 8%. It is thus indicated that the combined addition of EA and SAP could be an ideal approach to reduce the autogenous shrinkage of UHPC.

关 键 词：超高性能混凝土 膨胀剂 高吸水树脂 自收缩 强度 

分 类 号：TU528.572[建筑科学—建筑技术科学]