Structural Concrete Repair

Epoxy Pressure Injection

Epoxy pressure injection is the ability to inject multiple components, epoxy-based construction adhesives to bond concrete, and in some instances laminated wood structural beams. In addition, epoxy pressure injection is often used to bond delaminations and fill voids under equipment base plates to provide 100 percent bearing capacity. Structural restoration of concrete by epoxy pressure injection is very often the only alternative to complete replacement. It therefore results in large cost savings. Injection protects the rebar and stops water leakage. Epoxy pressure injection is a system for welding cracks back together. This welding restores the original strength and loading originally designed into the concrete. Epoxy pressure injection restores the structural quantities the concrete design intended. In other words, under most conditions it makes the concrete as good as new. It creates an impervious seal to air, water, chemical, debris and other contamination.

Applications

  • Stress cracks
  • Fractures
  • Shrinkage cracks
  • Base plate
  • Delaminations
  • Fill voids

Fiber Reinforced Polymers

Fiber-reinforced polymers (FRP) (also fiber-reinforced plastics) is a composite material made of a polymer matrix reinforced with fibers. Externally or internally installed, FRP is engineered to increase the load capacity, strength and potentially provide protection from external environmental attack FRP is also an effective way of regaining structural integrity in structures where internal reinforcing has been damaged, compromised or has been installed incorrectly. FRP can be applied to strengthen the beams, columns and slabs in buildings and bridges. It's possible to increase strength of these structural members even after these have been severely damaged due to loading conditions.

For strengthening beams, two techniques are adopted. The first is to paste FRP plates to the bottom (generally the tension face) of a beam. This increases the strength of beam, deflection capacity of beam and stiffness (load required to make unit deflection). Alternatively, FRP strips can be pasted in 'U' shape around the sides and bottom of a beam, resulting in higher shear resistance.

Columns in building and bridges can be wrapped with FRP for achieving higher strength. This is called wrapping of columns. The technique works by restraining the lateral expansion of the column.

Slabs may be strengthened by pasting FRP strips at their bottom (tension) face. This will result in better performance, since the tensile resistance of slabs is supplemented by the tensile strength of FRP.

Applications

  • Change of occupancy to increase load capability
  • Upgrade load bearing capacities of concrete and masonry structures
  • Restore capacity of concrete structures loss due to deterioration
  • Correct design/construction errors
  • Seismic Retrofit
  • Environmental protection for concrete members exposed to environmental attack

Spall Repair

Repair to concrete structures where concrete has been damaged from external forces, environmental, mechanical damage, or chemical exposure and attack.

A spall in a concrete surface may be the result of localized distress or the symptom of a more widespread distress in the concrete element. In either case, an attempt should be made to determine the cause of the distress prior to taking corrective action. This can easily be accomplished by retaining the services of a reputable architectural firm, engineering firm, or contractor.

Spall repair is not a band-aid to a structure in distress; it is a complex engineering task with challenges substantially different from those associated with new construction. This intricacy increases with the age of the structure and the severity of deterioration.

Standard practice for the repair of concrete spalls vary depending on the type of concrete element being repaired, cause and extent of damage, location of the spall and material selected. The repair material selection is typically based on such factors as properties of the repair material, climatic conditions, repair time frame, expected service life and cost.

The repair process generally includes: 1) a physical inspection to document the details and extent of damages, 2) an assessment to determine the cause of distress, 3) the selection of repair materials and 4) the selection of an experienced contractor who specializes in concrete repair work.

Repair methods include hand applied mortars, form and pump, shotcrete and gunite repairs. Our shotcrete nozzlemen are certified by the American Concrete Institute.

Applications

  • Slabs
  • Columns
  • Beams
  • Walls
  • Girders