NRG Energy retrofitted its Indian River power generating station Units 3 and 4 with Air Quality Control Systems (AQCS) to meet future air pollution regulations. Selective Catalytic Reactors (SCRs,) Pulse Jet Fabric Filters (PJFFs,) Circulating Dry Scrubber (CDS) systems, Induced Draft Fans, and associated facilities were added to Units 3 and 4. GTA was the Project Engineer responsible for supervising construction observation and material testing services for the project including various deep foundation systems, such as, Micro-Piles, Auger Pressure Grouted Displacement Piles, and Auger Pressure Grouted Piles (36-inch and 16-inch nominal diameters). Our services also included observation and testing for concrete pile cap and structural slab construction and density testing of fill construction.
Services included Forensic evaluation and sampling. Testing was to evaluate concrete placed for a pile caps supporting a byproduct silo type structure. Due to the large mass of concrete required to construct the pile cap, delays in concrete delivery raised the issue of possible cold joints forming in the pile cap. GTA performed concrete coring to obtain cores for compressive strength testing and petrographic analysis. We also evaluated potential overstressing of structural steel support framing using strain gages as the structure was loaded. Finally, we evaluated steel reinforcement bar Yield and Tensile Strength, & Elongation for selected pieces of rebar from 36-Inch Diameter APG Piles.