Problem:
Concrete slab for both Radio Shack and Mattress Discounters was settling down toward the front of the units. A significant void was discovered underneath the floor slab, most likely caused from improper subgrade preparations.  Removal and replacement of the slab was not feasible in the both the overall cost and disruption to the existing tenants. 

Engineering Design:
An engineer from Northeast Helical utilized a laser level to determine the approximate area affected by the settlement.  An approximate volume was then calculated to properly fill the void space.  A major consideration in the work was the slab could not be raised at all, as a glass façade was built upon the concrete, which could break with any amount of lift. 

Project Details: 
Northeast Helical mobilized portable equipment to pressure grout the void space without disturbing the surrounding businesses.  Approximately 45 cubic feet of material was pressure injected through the existing slab, effectively filling the empty space below the concrete.  The work was successfully completed in two working days.