Experimental Test of Reinforced Timber of FRCM-PBO with Pull-Off Adhesion Method

Area of Science:

• Materials Science
• Civil Engineering
• Structural Engineering

Background:

• Fiber Reinforced Cementitious Matrix (FRCM) composites are increasingly used in structural retrofitting.
• Epoxy resins serve as crucial bonding agents in composite material applications, particularly with timber structures.
• Understanding the adhesion strength of FRCM-PBO and epoxy resin systems is vital for their effective application in timber beam connections.

Purpose of the Study:

• To evaluate the pull-off adhesion strength of FRCM-PBO composites bonded to an epoxy resin layer on timber beams.
• To assess the pull-off resistance of the epoxy resin layer directly from a pine timber substrate.
• To analyze the correlation between test results and destructive forces using Pearson linear correlation.

Main Methods:

• Pull-off adhesion tests were conducted on FRCM-PBO/epoxy/timber and epoxy/timber systems.
• Testing followed the Polish Standard PN-EN 1542.
• Pearson linear correlation analysis was employed to examine relationships between adhesion strength and failure loads.

Main Results:

• All tested samples exhibited non-initial adhesive failure between the adhesive layer and the test disc.
• Characterization of factors influencing test outcomes, including force application, surface preparation, and substrate failure modes, was performed.
• Data on the pull-off resistance of both the composite-to-epoxy and epoxy-to-timber interfaces were obtained.

Conclusions:

• The study provides critical data on the adhesion performance of FRCM-PBO and epoxy resin systems on timber.
• Non-initial adhesive failure suggests potential for improved bonding strategies or material selection.
• The findings contribute to the reliable application of these materials in timber structure strengthening and repair.