高延性纤维混凝土抗压性能试验研究
doi: 10.13204/j.gyjz201504023
EXPERIMENTAL STUDY OF COMPRESSIVE BEHAVIOR OF ENGINEERED CEMENTITIOUS COMPOSITES
-
摘要: 高延性纤维混凝土(ECC)具有应变硬化和多裂缝开展性能,能明显改善混凝土结构的抗裂性能和耐损伤能力。通过对9组不同配比的高延性纤维混凝土的抗压性能进行试验研究,并与砂浆基体和混凝土进行比较,得出以下结论:1)高延性纤维混凝土试块受压破坏过程中表现出良好的抗压韧性,与普通混凝土和砂浆基体的破坏明显不同;2)第2次加载时,裂缝截面处的纤维承担了大部分拉力,纤维受拉和拔出过程中试块内部形成多而细密的裂缝,使材料在破坏过程中逐渐释放能量;3)在保证纤维分散性和拌合物流动性的情况下,水胶比越低,抗压强度越高,粉煤灰掺量增大可以改善纤维和基体的界面特性、提高材料的延性;4)高延性纤维混凝土的第2次抗压强度与第1次抗压强度接近,受损后强度在一定程度上仍继续保持增长,其耐损伤能力明显优于普通混凝土。Abstract: Engineered cementitious composite ( ECC) can significantly improve the anti-cracking performance and damage resistance ability of concrete structure due to its pseudo strain hardening and multiple cracking performances. Specimens of 9 groups with different mix of engineered cementitious composite were designed and their compressive properties were tested. By comparing with concrete and mortar matrix,the following conclusions were drawn: 1) engineered cementitious composite showed good compressive resilience in the compression failure,which was markedly different from ordinary concrete and mortar matrix; 2) on the secondary loading,the fiber of the fractured cross-section carried most of the tension and multiple cracks occurred within the specimens,which made energy releasing during damage of the material; 3) on the condition of full dispersion of fiber and liquidity of mixture,the lower the water-binder ratio,the higher the compressive strength,and the increase of fly ash could improve interface property and ductility of the material; 4) the secondary compression strength of engineered cementitious composite was close to its first compression strength and its strength continued to grow to some extent even after damaged, so its ability of resistance to damage is significantly better than that of ordinary concrete.
点击查看大图
计量
- 文章访问数: 213
- HTML全文浏览量: 16
- PDF下载量: 732
- 被引次数: 0