Title:
Effect of Silica Fume with Crystallizing Admixture on Self-Healing ECC (Prepublished)
Author(s):
Hinoel Ehrenbring, Fernanda Pacheco, Roberto Christ, and Bernardo Tutikian
Publication:
Materials Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
crystallizing admixture; engineered cementitious composites; polymer fibers; self-healing; silica fume
DOI:
10.14359/51749265
Date:
10/20/2025
Abstract:
This study aimed to evaluate the effect of isolated silica fume (SF) and SF combined with three contents of crystalizing admixture (CA) in the self-healing of engineered cementitious composites (ECCs) with different polymeric fibers. Self-healing was evaluated in coupon specimens subjected to bending to produce cracking. Healing products were evaluated in the cracks within 84 days. Exposure conditions for self-healing were water-saturated (SAT) and wet-dry cycles (WD). The results showed that the composites with isolated SF presented a continuous layer of healing product covering widths of up to 100 μm. The final widths for these composites were 40 μm for different conditions. In composites with CA, the volume of product generated (gel) was considerably greater, causing it to leak out of the microcracks existing in the ECC, impairing healing. Thus, the results showed that the use of SF+CA reduced the ECC healing potential. Healing from the crystallizing admixture was spot-wise only, decreasing its healing potential. The performance of the crystallizing additive was impaired under wetting and drying conditions. Leaching was observed both under SAT and WD exposure conditions. More leaching was observed from WD, while SAT formed a more uniform product layer.