220 / 2022-06-10 15:39:57

Toughness Enhancement of Equivalent Self-Compacting Concrete Mortar Through Synergistic Effects of Multi-component

Self-compacting concrete,Equivalent mortar,Multi-component toughening,Fracture properties,Synergy effect

In this work, three toughening components (i.e., rubber particles, polymer latex powder, and polypropylene fiber) were adopted to explore their synergistic toughening effects on the self-compacting concrete equivalent mortar.

Firstly, self-compacting concrete equivalent mortar containing different combinations of these toughening components was designed and manufactured. Subsequently, three-point bending fracture tests were conducted to obtain the P-CMOD curve, and fracture parameters were calculated and compared, including critical crack tip opening displacement, critical effective crack length, unstable fracture toughness, fracture energy, and ductility index. Additionally, the micro interface characteristics are analyzed to explore the synergistic mechanism of the three components.

The results show that when rubber, latex powder, and fiber are mixed at the same time by any two components, the fracture energy of the specimen is higher than that of the single mixing group under the same volume, and the synergistic effect factors of fracture energy of the double mixing group are positive, indicating that the two components can play a positive synergistic effect and improve the fracture toughness of the specimen to a certain extent. The synergistic effect factors of the three mixed groups are also positive, indicating that the three components can cooperate with each other to further exert the positive synergistic toughening effect. The micro interface morphology shows that the organic film with certain toughness formed by latex powder can improve the structure of the interface transition zone between rubber, fiber, and cement paste, increase the compactness of the structure, and improve the toughness of the equivalent mortar of self-compacting concrete.