Boeing Airfield

PROBLEM:

The concrete assembly ramps are 13 inches thick. Random fine cracks have developed as a result of the loading and unloading of C-17 aircraft taxiing across them over time. The cracks have enlarged, and additional small cracks have propagated from them. These cracks lead to the formation of concrete fragments, foreign object debris (FOD), which can become airborne and have the potential of being sucked into jet engines causing damage.

Boeing has investigated various methods including epoxy injection for stabilizing the concrete surface to prevent fragmentation and FOD. Surtreat West, LLC was invited to conduct a demonstration of the Surtreat® concrete protection and restoration process on a 750 sq. ft. section of the ramp August 17, 2001.

LEFT: Assembly Ramp 17, test area before SURTREAT application.

SOLUTION:

The Surtreat® process involves the surface application of water soluble chemical formulations, which penetrate the surface to a minimum depth of 2 inches, and react with the cement phase to increase strength, decrease porosity, and inhibit rebar corrosion and cement chemical degradation.

OUR PROCESS:

Surtreat West, LLC. applied 7.5 gallons of SURTREAT – GPHP (TPS II) to 750 sq. ft. of taxiway surface on August 17, 2001. Multiple applications of SURTREAT –GPHP (TPS II) were made. Concrete compressive strength was measured before and after applications of SURTREAT – GPHP (TPS II) in accordance with ASTM Testing Procedure C900-01. The after application measurements were taken 84 days later on November 10th, 2001.

ABOVE: Surtreat treated surface acquires a slightly darker, shiny appearance.

TESTING:

Concrete strength is determined by measuring the force in kilo Newton’s (kN) required to pull a 2 x 1 inch plug from the concrete surface. This force is also expressed in the more conventional psi compression strength scale.

The increase in overall strength is very significant in percentage terms, and demonstrates how Surtreat – GPHP (TPS II) can increase the surface strength of concrete. It is anticipated that the increase may be even greater in areas along the crack faces, which have become weak and are prime sources of fragments and FOD. Surtreat inhibits the formation of FOD by increasing concrete strength.

ABOVE: After application plug doesn’t crumble, showing improvement.