Date: February, 2011
Location: Indianapolis, Indiana
Contractor: AccuLevel, Rossville, IN
Engineer: Hayman Residential Engineering
In this case, the load of building was causing compression cracking of precast panels, resulting in hundreds of spider cracks which affected the compression, shear and tensile strength of the foundation walls.
Due to labor costs, precast panels and other pre-fabricated materials are seeing increasing use. These and other concrete structures, as a result of compression, shear, and tensile pressures can develop stress cracks that look like spider webs throughout the foundation wall. These are signs of a failing structural integrity and need immediate repair.
Precast Sandwich Panels set in place were 6" foam insulation sandwiched between 2" of 5,000 psi concrete. The load of building was causing compression cracking of precast panels, resulting in hundreds of spider cracks. Due to the brick building and size of unit, replacement of wall was not an option. Even after epoxy injection of large cracks the spider cracks continued.
Engineer designed using 600gsm fabric in a manner of wind/seismic upgrade. Taking loads back to corners, slab and back up to dead load of building. Thus increasing compression, shear and tensile strength of under-designed foundation walls. Application of carbon fiber was completed in 4 days.