PP纤维高强混凝土的和易性及高温后抗压强度的试验研究

Experiment and Research on Workability and Compressive Strength After High Temperature of HSC with Polypropylene Fiber

通过试验 ,研究了PP纤维掺量对高强混凝土用水量及和易性的影响。结果表明 :保持和易性不变情况下 ,高强混凝土的用水量随PP纤维掺量的增加而逐渐增大 ;保持用水量不变时 ,高强混凝土的和易性随PP纤维掺量的增加逐渐变差 ,混凝土坍落度逐渐减小。PP纤维掺入后 ,高强混凝土的抗压强度明显下降 ,高温后高强混凝土试件的颜色随受热温度的升高逐渐变浅 ,由常温时的深灰色逐渐变为灰白色、米色 ,抗压强度也逐渐降低 ,且掺与不掺PP纤维的高强混凝土抗压强度的变化规律相同 ,降低幅度基本相同 。

Effects of dosage of polypropylene fiber on water consumption and workability of high strength concrete (HSC) were studied experimentally. On condition that keeping workability invariability, the water consumption of HSC improves gradually with dosage of polypropylene fiber increased. If the water consumption is the same, the workability becomes worse and worse with polypropylene fiber dosage increased and concrete slump decreases gradually. The compressive strength declined distinctly after the polypropylene fiber is mixed. The color of HSC after high temperature turns thin with heated temperature increased and turns deep gray into ash gray and beige. The compressive strength reduces gradually and changing rule is the same if polypropylene fiber was mixed or not. The reducing extents are nearly the same. The corresponding regressive formula was given.. 〔