Outlet Structure Assessment & Repairs

Voss Laboratories completed a comprehensive concrete condition assessment of this lower level outlet to evaluate deterioration mechanisms and characterize the extent of damage. The walls and beams of the structure had been exposed to decades of freeze-thaw cycling. Vertical cracks in the walls had perpetuated severe freeze thaw damage.

Field Inspection Scope

• Visual investigation

• Delamination survey to map freeze thaw areas

• Surface Penetrating Radar

• Concrete Coring

Lab Testing Scope

• Visual inspection of cores

• Modulus of Elasticity

• Compressive Strength

• Pulse Velocity

• Petrographic Examination

A combination of visual inspection and stepped pulse velocity testing was able to determine the exact depth of freeze thaw attack. Voss Labs designed the repair specification which included guidance for partial depth repairs, epoxy crack injection, and material selection. VL engineers performed tensile pull off testing per ASTM C1583 to verify proper preparation of substrate and application of the repair material. This project successfully extended the life of this critical hydropower asset.