Sun, Charlie; University of Kentucky, Lexington, Kentucky Transportation Center, College of Engineering
Kentucky Transportation Cabinet
Compressive strength; Concrete structures; Pull out test; Construction
Current practice for determining the compressive strength of structural concrete consists of two methods. For newly placed concrete, test cylinders are prepared on‐site and then taken to determine compressive strength. For existing concrete, cores are taken from the in‐place concrete and then tested to evaluate the compressive strength. Both practices require testing at an off‐site facility. This requires the affected parties on the project site to wait for the samples to be delivered, tests performed, test data analyzed, and results returned to the project site. Analysis of existing structural concrete requires extraction of core samples from the structural element in question, introducing the need to patch and repair sample locations as well as the possibility of damaging the structural integrity. A quick, on‐site method with minimal repair is needed to determine the compressive strength of concrete. The Lateral Pull Off Test (LOF) for determining the compressive strength of in‐place concrete appears to be an accurate, non‐destructive, and reliable procedure. The objectives of this research are to: 1) Verify that data provided by LOF testing is consistent with those provided by current methods used to determine concrete compressive strength; 2) Validate LOF as a means of determining concrete compressive strength; and 3) Develop specifications to use LOF to assess concrete compressive strength.