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通过对不同聚乙烯醇(PVA)纤维体积掺量、水胶比、砂胶比的工程纤维增强水泥基复合材料(ECC)进行单轴受压性能试验,测得了其抗压强度及单轴受压应力-应变全曲线,主要分析PVA-ECC的破坏形态、受压性能及试件尺寸、加载速率对PVA-ECC立方体抗压强度的影响。结果表明:随着PVA纤维体积掺量的增加,PVA-ECC的抗压强度、峰值应变及极限应变均明显增大,试件塑性变形能力也越好;水胶比增大,PVA-ECC的抗压强度降低,但试件达到峰值后延性增加;砂胶比为0.36时,PVA-ECC的抗压强度和压缩韧性最大。PVA-ECC的立方体抗压强度存在尺寸效应:f100cu∶f70.7cu∶f40cu=0.93∶1∶1.15;加载速率越大,PVA-ECC的立方体抗压强度越高,且对于不同强度的PVA-ECC,加载速率的影响趋势相同。根据试验结果得出立方体抗压强度、峰值应变与纤维体积掺量的关系、轴心抗压强度与立方体抗压强度的关系。
The uniaxial compression tests of engineering fiber reinforced cement-based composites (ECC) with different volume ratios of polyvinyl alcohol (PVA) fibers, water-binder ratio and sand-cement ratio were carried out. The compressive strength and uniaxial strength Compressive stress - strain curve, the main analysis of the PVA-ECC damage morphology, compression properties and specimen size, loading rate on the compressive strength of PVA-ECC cube. The results show that the compressive strength, peak strain and ultimate strain of PVA-ECC increase obviously with the increase of volume content of PVA fiber. The plastic deformation capacity of PVA-ECC also increases. The compressive strength decreased, but the ductility increased when the specimen reached the peak value. The compressive strength and compressive toughness of PVA-ECC were the highest when the ratio of mortar to binder was 0.36. PVA-ECC cubic compressive strength size effect: f100cu:f70.7cu:f40cu = 0.93:1:1.15; the higher the loading rate, the higher the cubic compressive strength of PVA-ECC, and for different strength of PVA-ECC , The loading rate of the same trend. According to the test results, the relationship between the cubical compressive strength, the peak strain and the fiber volume content, the relation between the compressive strength of the core and the compressive strength of the cubes are obtained.