New Research Confirms Strong Bond of V-ROD GFRP Bars in Shotcrete

When it comes to designing durable, corrosion-free infrastructure, bond performance is one of the most critical factors engineers must evaluate. And now, thanks to new peer-reviewed research, there’s even more confidence that V‑ROD® GFRP bars are up to the task — even in challenging shotcrete applications.

Published in the ASCE Journal of Composites for Construction, this study by the research team at Queen’s University presents one of the most comprehensive bond and development-length programs ever conducted for GFRP reinforcement in both shotcrete and cast-in-place concrete.

Key Findings from the Study

1. Superior Testing Method, Reliable Results

Rather than relying on simple pullout tests, the researchers used notched-beam bond tests — a more rigorous and representative method for assessing bond.

The result? Sand-coated V‑ROD® bars delivered high, consistent bond strength in both shotcrete and poured concrete.

2. Comparable Performance in Shotcrete and Poured Concrete

When properly encapsulated, V‑ROD®’s bond performance in shotcrete matched that of poured concrete, with only modest reductions that were attributed to localized voids.

3. A Better Predictive Model for Development Length

The study proposes a new model that more accurately predicts development length for GFRP reinforcement, giving engineers a powerful new tool for designing safe, durable, and efficient structures.

Why This Matters for Designers and Owners

Bond strength is a cornerstone of structural integrity. These findings confirm what V‑ROD users have experienced in the field for years:

 – Reliable performance in a variety of construction methods
– Durability in harsh, corrosive environments
– Confidence in the long-term service life of critical infrastructure

Whether you’re designing tunnels, bridges, retaining walls, or repair projects, V‑ROD® gives you peace of mind — and data-backed assurance — that your reinforcement will perform as expected.

Read the full study: ASCE Journal of Composites for Construction