Title:
Effect of Surface Preparation Techniques on Concrete-Grout Interfaces (Prepublished)
Author(s):
Anthony Addai Boateng, Garrett Tatum, Natassia Brenkus
Publication:
Materials Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
cementitious grout; chloride ion; epoxy grout; surface preparation; tensile bond strength
DOI:
10.14359/51744378
Date:
11/22/2024
Abstract:
Pour-backs and overlays are utilized commonly in bridge elements and repairs; it is crucial to corrosion protection that the bond between grout and concrete in these regions is carefully constructed. The integrity of the bond is crucial to ensure a barrier against water, chloride ions, moisture, and contaminants; bond failure can compromise the durability of concrete structures' long-term performance. This study examines the influence of surface preparation methods on the bond durability and chloride permeability between concrete substrate and grouts, including both "non-shrink" cementitious and epoxy grouts. A microstructural analysis of scanning electron microscopic (SEM) images was conducted to characterize the porosity of specimen interfaces. Pull-off testing was performed to quantify tensile strength. Results show that a water-blasted surface preparation technique improved the tensile bond strength for cementitious grout interfaces and reduced porosity at the interface. In contrast, epoxy grout interfaces were less affected by surface preparation. The study establishes a relationship between chloride ion permeability, porosity, and bond strength. The findings highlight the importance of surface preparation in ensuring the durability of concrete-grout interfaces.