【摘要】 选取钢纤维和玄武岩纤维进行试验,研究了两种纤维掺量以及硅灰掺量对超高强水泥基复合材料抗压抗折强度、疲劳性能以及体积收缩率的影响。结果表明,纤维和硅灰的加入能有效改善水泥基材料的力学及收缩性能,钢纤维对水泥基材料强度提升较大,但玄武岩纤维表现出与材料更好的相容性,1.5%钢纤维、0.1%玄武岩纤维改善效果最明显,抗折、抗压强度分别提高了12.6%、3.0%和21.2%、2.7%,体积收缩率降低了12.2%、5.4%,且1.5%钢纤维的疲劳寿命是不掺纤维的近4倍,最大跨中挠度曲线呈现明显的阶段性特征;8%硅灰改善效果最大,抗折、抗压强度分别提高了13.3%、10.4%,体积收缩率降低了28.8%。更多还原

【Abstract】 Steel fiber and basalt fiber were selected for experiment, and the effects of the amount of two fibers, the amount of silica fume on the compressive and flexural strength and volume shrinkage of ultra-high strength cementitious composites were explored. The results show that the addition of fiber and silica fume can effectively improve the mechanical and shrinkage properties of cementitious composites. Steel fiber has great improvement in strength for cementitious composites, but basalt fiber exhibits better compatibility with materials. 1.5% steel fiber or 0.1% basalt fiber has the greatest improvement for the cementitious property, and the flexural and compressive strengths are increased respectively by 12.6%, 3.0% and 21.2%, 2.7%, respectively. The volume shrinkage rate is reduced respectively by 12.2%and 5.4%. The fatigue life of the specimens with 1.5% steel fiber is nearly 4 times that of the specimen without fiber, and the maximum mid-span deflection curve shows obviously characteristics of stages. 8% silica ash has the greatest improvement effect. The flexural and compressive strength increased respectively by 13.3% and 10.4%, and the volume shrinkage rate is decreased by 28.8%.更多还原