Service Life of Patches in Concrete Flat Slabs

Many of today’s ageing reinforced concrete structures have reached or exceeded their expected service life and a significant number of newer structures exposed to severe environmental conditions are showing premature deterioration within 20 years of construction (Mehta, 1991). So far, the strategy has been repair and rehabilitation rather than replacement, resulting in an estimated annual cost of repairing structures in North America between 11 and 15 billion American dollars (Chidiac, 1997). However, repair not only has a more recent history, it does not have established codes from which a proper design can be followed.