In precast concrete segmental bridges, epoxy adhesive is applied to joints, serving multiple essential functions as outlined by the International Road Federation (1977):
Complete Joint Sealing: The adhesive forms an airtight seal between precast segments, shielding the prestressing tendons from detrimental environmental factors, thereby preserving their integrity and extending their lifespan.
Stress Concentration Reduction: By meticulously filling voids and irregularities along joint surfaces, epoxy adhesive minimizes stress concentrations that would otherwise develop at these discontinuities. This stress redistribution contributes to the overall structural resilience and durability of the bridge.
Shear Transfer Enhancement: When a large single shear key is employed, epoxy adhesive facilitates efficient shear transfer between the precast segments. This adhesive bond ensures the segments act as a unified structure, effectively distributing loads and enhancing the bridge’s overall load-bearing capacity.