超高性能混凝土工作性改善措施研究  

Study on Workability Improvement of Ultra-High Performance Concrete

作　　者：沈锐 李云军 Shen Rui;Li Yunjun

机构地区：[1]重庆大学材料科学与工程学院,重庆400030 [2]重庆天维绿色建筑技术开发有限公司,重庆400700

出　　处：《重庆建筑》2020年第1期37-39,共3页Chongqing Architecture

基　　金：重庆市建设科技计划项目“超高性能组合钢桥面铺装应用技术研究”;重庆市技术创新与应用示范社会民生类一般项目“RPC井盖等市政构件研究开发及产业化”(cstc2018jscx-msyb X0145)

摘　　要：该文研究了不同水胶比下,细骨料级配及粗骨料取代细骨料的比例对超高性能混凝土(UHPC)工作性能和力学性能的影响。试验结果表明:骨料的比表面积(SSA)能较好地描述UHPC流动度的变化;通过改变骨料的级配来降低SSA可提高UHPC的流动性,但会降低UHPC的抗压强度;通过用粗骨料部分取代细骨料的方法能改善UHPC的工作性,对UHPC抗压和抗折强度的影响与粗骨料粒径和取代比例有关,且对抗折强度的影响要大于抗压强度。This paper studies the effects of fine aggregate gradation and the ratio of coarse aggregate replacing fine aggregate on the workability and mechanical properties of UHPC under different water-to-cement ratios. The obtained results indicated that the specific surface area(SSA)of aggregate could well describe the fluidity variation of UHPC. Changing aggregate gradation to reduce SSA could improve the fluidity of UHPC while reducing the compressive strength of UHPC. By partially replacing fine aggregate with coarse aggregate, the workability of UHPC could also be improved, but its influences on the compressive and flexural strength of UHPC was related to the particle size of coarse aggregate and the substitution ratio and the impact on the flexural strength was greater than the compressive strength.

关 键 词：超高性能混凝土 工作性 骨料 级配 

分 类 号：TU528[建筑科学—建筑技术科学]