利用未淡化海砂配制超高性能混凝土的研究

利用未经淡化处理的海砂配制了超高性能混凝土(UHPC),并研究了不同水胶比、砂胶比、胶凝材料体系、钢纤维掺量、养护制度对海砂UHPC的流动度、抗压强度、抗折强度的影响。试验结果表明:海砂UHPC的最优水胶比、砂胶比和纤维体积掺量分别为0.16、1.0和1.5%,最佳的胶凝材料体系组成是水泥、降黏剂和硅灰分别70%、15%和15%,最合适的热养护制度是70℃蒸汽养护;按照上述参数配制的海砂UHPC力学性能完全符合相关标准的要求。

Study on Ultra-high Performance Concrete Used by Untreated Sea Sand

Ultra-high performance concrete (UHPC) was prepared by mixing with untreated sea sand, and the effect of different W/B, sand-binder ratio, cementitious systems, steel fiber volume contents, curing schedules on the fluidity, compressive strength and flexural strength of UHPC with untreated sea sand are studied. The results show that: the optimum W/B, sand-binder ratio and steel fiber volume content of UHPC made with untreated sea sand are 0.16, 1.0 and 1.5% respectively;the optimum cementitious system is composed of 70% cement, 15% viscosity reducer, and 15% silica fume;the most suitable curing schedule is steam curing in the temperature of 70 ℃;and according to the above parameters, the mechanical property of UHPC with untreated sea sand can meet the requirements of current national standard.