高温后聚乙烯醇纤维混凝土受压破坏声发射特性研究

通过基准混凝土和聚乙烯醇(PVA)纤维混凝土高温后单轴压缩试验,研究聚乙烯醇纤维混凝土在高温后力学性能的变化规律以及利用声发射(AE)技术对试验全过程进行了动态监测。结果表明:聚乙烯醇纤维的掺入使混凝土的耐高温性能得到了增强;高温后混凝土声发射能量累计数变化大致分为压密、线弹性、塑性、破坏四个阶段;聚乙烯醇纤维混凝土的能量计数率分布较基准混凝土更广,峰值能量计数率相对较小,聚乙烯醇纤维掺入提高了混凝土高温后的延性。

Study on acoustic emission characteristics of polyvinyl alcohol fiber concrete compression damage after high temperature

Through the uniaxial compression experiment of reference concrete and polyvinyl alcohol(PVA)fiber reinforced concrete after high temperature,the variation regularity of mechanical properties of polyvinyl alcohol fiber reinforced concrete after high temperature and the dynamic monitoring of the whole process were studied by using Acoustic Emission(AE)technology.Studies have shown that the incorporation of PVA fiber enhances the high temperature resistance of concrete.The cumulative variation of acoustic emission energy of concrete after high temperature is roughly divided into four stages:compaction,Linear elasticity,plasticity and failure stage;The polyvinyl alcohol fiber reinforced concrete The energy count rate distribution is wider than that of the reference concrete,and the peak energy count rate is relatively small,Admixture of Polyvinyl alcohol fiber improves the ductility of concrete after high temperature.