- 目录
- 混凝土与制品
- 首页
触变剂对超高性能混凝土性能的影响研究
作者：刘子源1，李磊1，柯伟席2，成良民1，陈林1，邹伟2
（1.武汉三源特种建材责任有限公司，湖北 武汉 430080；
2.武汉源锦建材科技有限公司，湖北 武汉 430080）
摘要：为减少超高性能混凝土（UHPC）在坡面施工时无法有效保持定型问题，研究了触变剂对UHPC工作性能、力学性能的影响，并采用流变仪测试了掺触变剂UHPC的流变性能，采用修正后Bingham流体模型，对掺触变剂UHPC的屈服应力与塑性黏度进行计算。结果表明：随着触变剂掺量的增加，坡面流动度减小，UHPC的屈服应力提高，塑性黏度增大，且增大了UHPC的触变性。触变剂掺量为0.2%时，流动度与斜面流动度较空白组分别减小了12.8%、30.7%，28 d抗压强度较空白组降低了4.2%；其屈服应力和塑性黏度分别为96.53 Pa和67.25 Pa·s，较空白组分别提高了19.0%和3.5%；当触变剂掺量超过0.4%时，对其流动度及抗压强度影响较大，不宜在UHPC中超掺使用。
关键词：触变剂；超高性能混凝土；流动度；流变性；抗压强度
中图分类号：TU528.31 文献标识码：A 文章编号：1001-702X（2022）07-0028-04
Study on the effect of thixotropic agent on ultra-high performance concrete
LIU Ziyuan1，LI Lei1，KE Weixi2，CHENG Liangmin1，CHEN Lin1，ZOU Wei２
（1.Wuhan Sanyuan Special Building Materials Co. Ltd.，Wuhan 430080，China；
2.Wuhan Ujoin Building Material Technology Co. Ltd.，Wuhan 430080，China）
Abstract：In order to reduce the problem that ultra-high performance concrete（UHPC） could not effectively maintain the shape during slope construction，the influence of thixotropic agent on the working performance and mechanical properties of UHPC was studied. The rheological properties of UHPC doped with thixotropic agent were analyzed by rheometer，and the yield stress and plastic viscosity of UHPC doped with thixotropic agent were calculated by modified Bingham fluid model. The results show that with the increase of thixotropic agent content，the slope fluidity decreases，the yield stress of UHPC increases，the plastic viscosity increases，and the thixotropy of UHPC increases. When the dosage was 0.2%，the fluidity and incline fluidity of the blank group were 12.8% and 30.7% lower，and the compressive strength of standard culture for 28 days was 4.2% lower. The yield stress and plastic viscosity are 96.53 Pa and 67.25 Pa·s，respectively，which are 19.0% and 3.5% higher than those of blank group. When the thixotropic agent content is more than 0.4%，its fluidity and compressive strength are greatly affected，so it is not suitable for use in ultra-high performance concrete.
Key words：thixotropic agent，ultra-high performance concrete，fluidity，rheological properties，compressive strength