Repair of (3) 550' x 53' - 6" Reinforced Concrete Chimneys

Hazardous conditions from spalling concrete prompted plant personnel to contract Jansons Gibraltar to repair the structures using a two-phased approach. Initially, Jansons Gibraltar conducted a comprehensive inspection to assess the overall condition and at the same time remove all spalling concrete from the (3) 550' tall concrete chimneys at the Joppa Steam Sta. The inspection included: 

  • Diamond-blade saw cutting the perimeter of spalled areas to remove all safety hazards

  • Hammer Sounding and mapping the concrete surface

  • Conducting covermeter testing to assess reinforcing steel embedment depth and reinforcing bar corrosion

  • Obtaining core samples for compressive tests and petrographic analysis; as well as evaluating carbonation and chloride attack

Phase II involved performing approximately 4,000 SF of concrete repairs and involved:

  • Abrading/roughening the concrete surface

  • Cleaning reinforcing steel and coating with Zinc-rich primer
  • 'Forming & pouring’ larger and deep locations with an expoxy repair mortar
  • ‘Hand-patching’ of localized repairs with a vertical & overhead epoxy repair mortar

  • Repairing all stress cracks and open construction pour seams