PVA纤维水泥基复合材料抗折试验研究与模型分析

Experimental study on fracture resistance of PVA fiber reinforced cement based composites and model analysis

PVA纤维水泥基复合材料有着显著阻裂能力和拉伸性能,开展了PVA纤维水泥基材料抗折性能的研究。包括PVA纤维水泥基复合材料试件抗折性能试验、其破坏形态与承载力分析、建立与分析了在PVA纤维水泥基复合试件下的拱模型理论、提出新的承载力计算方法。研究得出:PVA纤维水泥基复合材料试件在纤维体积掺量为0.5%、1.0%、1.5%、2.0%时,抗折承载力随着纤维掺量的增加而增加,抗折性能得到显著提升;根据PVA纤维水泥基复合材料试件的不同受力阶段,分3种情况建立平衡方程,为计算抗折承载力提供了依据;建立了拱模型在PVA纤维水泥基复合材料试件下的抗折承载力计算理论,得到抗折承载力计算结果与试验值较为接近。

PVA fiber reinforced cement-based composites have significant crack resistance and tensile properties.The flexural properties of PVA fiber reinforced cement-based materials were studied.It includes the experiment of flexural performance of PVA fiber reinforced cement-based composite specimens,the analysis of its failure mode and bearing capacity,the establishment and analysis of arch theoretical model under PVA fiber reinforced cement-based composite specimens,and the new calculation method of bearing capacity.The results show that the flexural capacity of PVA fiber reinforced cement-based composites increases with the increase of fiber content when the fiber volume content is 0.5%,1.0%,1.5%and 2.0%.According to the different loading stages of PVA fiber reinforced cement-based composite specimens,the equilibrium equations are established in three cases,which provide the basis for calculating the flexural capacity.The calculation theory of flexural capacity of arch model under PVA fiber reinforced cement-based composite specimens is established,and the calculated results of flexural capacity are close to the experimental values.