纤维对海砂超高性能混凝土性能的影响

Influence of fiber on ultra-high performance concrete with sea sand

采用未经淡化处理的海砂配制超高性能混凝土(UHPC)对于岛礁建筑具有重要意义。通过水泥胶砂的力学性能和流动度试验确定了海砂UHPC的基准配合比,研究了钢纤维和PVA纤维对海砂UHPC力学性能和流动度的影响。试验结果表明:随着钢纤维体积掺量的增加,海砂UHPC的抗压和抗折强度提高,综合考虑力学性能和经济性,钢纤维最优体积掺量为1.5%。当钢纤维体积掺量为1.0%时,PVA纤维等体积完全取代钢纤维对抗压强度影响不大,抗折强度降低22.5%;当钢纤维体积掺量为1.5%时,混杂体积掺量0.75%以内的PVA纤维对抗压和抗折强度的影响不大,但流动性明显降低。

Ultra-high performance concrete（UHPC） prepared by undiluted treatment of sea sand has a great significance to the construction of reefs. The basic mix proportion of UHPC with sea sand was ascertained through mechanical ProPerty and fluidi- ty test of cement mortar,the influence of steel fiber and PVA fiber on mechanical property and fluidity of UHPC were investigated. The test results show that the compressive strength and fiexural strength of UHPC are improved with the increase of steel fiber volume content,the optimal volume content of steel fiber is 1.5% considering the mechanical properties and economy,when steel fiber volume content is 1.0%,PVA fiber completely replace steel fiber by volume has little effect on compressive strength and flex- ural strength decreases by 22.5%. When steel fiber volume content is 1.5%,PVA fiber mixed with volume of less than 0.75% has little effect on compressive strength and flexural strength, but the fluidity is obviously decreased.