Casimir J. Bognacki, known throughout the concrete world as Cas, is the chief of materials engineering at the Port Authority of New York and New Jersey. He is one of CC’s Most Influential People in 2012 for his work to redefine acceptance standards for concrete at the Port Authority’s many nationally important projects, including the World Trade Center reconstruction.
Bognacki joined the Port Authority 28 years ago. His group conducts the testing and jobsite inspection of construction materials including concrete for use on their capital and maintenance projects. Bognacki says the Port Authority is the only public agency in the New York City area that still operates a concrete lab. The Port Authority will spend $2 billion on projects at the World Trade Center this year and will do the same next year. Another recent high-profile project was the complete reconstruction of a runway at JFK Airport, switching from asphalt to concrete.
Bognacki says that the tradition in the New York City area was for specifications to provide concrete mix proportions with very high portland cement content. He challenged this concept, requiring the concrete producer to produce concrete mixes with much less cement and cementitious materials. “We do not provide mix designs in our bid documents,” he says. “We specify end-results with payment adjustments for the application.”
Bognacki thinks the challenge is to move past the idea that concrete must have high compressive strength. Instead, it should have in-place characteristics that fit its function on a project, including durability, measured as permeability and shrinkage. He points out that concrete isn’t repaired because of low strength, but rather its lack of durability. “We currently are replacing asphalt runway areas at JFK Airport with concrete. It should have a 40- to 50-year life cycle,” he says. Therefore, tests such as the rapid chloride permeability test are more important than compressive strength for quantifying durability. At the jobsite, the Port Authority uses the microwave test to assure that the concrete has the proper water content. “If we say mixes shouldn’t exceed a 0.40 water-cement ratio, we mean it. We turn away loads with too much water.”
Cas has been married to his wife Donna for 33 years and has three daughters, Danielle, Michelle, and Christina. He is a native New Yorker, born and raised in Brooklyn.
