高韧性纤维增强水泥基复合材料抗压性能

发布时间：2018-02-04 18:53

本文关键词： 应变硬化多缝开裂抗压强度　出处：《土木工程与管理学报》2017年02期 　论文类型：期刊论文

【摘要】：ECC是一种具备应变硬化和多缝开裂特性的新型纤维增强水泥基复合材料,具有良好的韧性、耐久性等。研究表明:水泥品种对ECC同龄期抗压强度的影响较小;纤维种类对ECC同龄期抗压强度影响较大;采用复合水泥配制ECC,以普通水泥为主配制ECC,以保证其强度;采用粉煤灰替代部分水泥时,替代比例不宜超过40%,以免影响ECC抗压强度。扫描电镜显示主要水化产物呈小绒毛状,基体内部有好多微气孔,进口PVA纤维在基体内部乱向分布,纤维断裂时呈片层状;国产PVA纤维在基体内部呈同一方向顺向分布,易有结团现象,纤维断裂时呈不规则形状。
[Abstract]:ECC is a new fiber reinforced cement matrix composite with strain-hardening and multi-joint cracking characteristics, which has good toughness. The results showed that the cement variety had little effect on the compressive strength of ECC at the same age. The type of fiber has great influence on the compressive strength of ECC at the same age period. ECCs are prepared with compound cement and ECCs mainly with common cement to ensure the strength of ECCs. When using fly ash to replace some cement, the substitution ratio should not exceed 40%, so as not to affect the compressive strength of ECC. Scanning electron microscope showed that the main hydration products were small wool, and there were many micropores in the matrix. The imported PVA fibers are distributed disorderly in the matrix, and the fibers are lamellar when they break. Domestic PVA fibers are distributed in the same direction in the matrix and tend to form clusters. The fibers are irregular in shape when the fibers break.
【作者单位】：北京市市政工程研究院;
【分类号】：TU528
【正文快照】： 随着混凝土工程日益向超大跨、超高层等方向发展,特别是桥梁、蓄水池、压力容器等对阻裂的要求越来越高,需要开发高韧性、大变形的新型水泥基复合材料[1]。普通混凝土具备抗拉强度低、易开裂、裂缝宽度难以控制等缺点,纤维的发展在一定程度上起到了减轻混凝土早期开裂,提高材

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