聚乙烯醇纤维增强水泥基复合材料的三轴受压性能试验研究

Experimental Study on Triaxial Compression Performance of Polyvinyl Alcohol Fiber Reinforced Cement-based Composites

在6种不同围压条样下,对由不同掺量体积率的聚乙烯醇(PVA)纤维制成的标准圆柱体Φ50 mm×100 mm试样进行常规三轴压缩试验,研究了围压和纤维体积率对试样的峰值应力、峰值应变及本构方程的影响。研究结果表明:在常规三轴受压状态下,随着围压及PVA纤维体积率的增加,试样的峰值应变大于峰值应力,破坏试样所做的功也随之增大,且围压对试样峰值应变及应力的影响程度比纤维体积率大,达到试样峰值应力之后,纤维体积率的影响显著下降。侧向围压对试样的横向变形及裂缝发展有显著的约束效果,应力应变曲线符合过镇海模型。

The standard cylindrical Φ50 mm×100 mm test piece made of different volume fraction of polyvinyl alcohol(PVA) fiber was used to carry out the conventional triaxial compression test under six different confining pressures, and the confining pressure value and fiber volume fraction were studied to find difference of peak stress, peak strain and constitutive equations. The results show that under the normal triaxial compression state, peak strain increases more than peak stress with the increase of confining pressure and PVA fiber volume fraction, and the work required to destroy the specimen is also increased. The effect of confining pressure on peak strain and stress is greater than that of the fiber, which effect is obviously reduced after reaching peak stress of the specimen. The confining pressure can effectively constrain the lateral deformation and crack development of the specimen, and stress-strain curve conforms to Z. H. Guo Model.